Heat pump sizing and brands?

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THY4373
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Re: Heat pump sizing and brands?

Post by THY4373 »

dalbright wrote: Wed Jun 05, 2024 4:07 am
Did you install the dual fuel intelli-heat? Or was this just the mitsubishi air handler? If you went the intell-heat route I would love to hear your thoughts on it as i've been leaning that way when my r-22 trane says its had enough someday (hopefully never).
I have a Mitsubishi Intelli-Heat installed for my downstairs system. Unfortunately it was installed after the heating season in late spring so no feedback on heating. So far I am happy with it. It replaced a 30-year old dual fuel heat pump/gas furnace system. My installer had done my upstairs system which is a heat pump only system and cut me a deal on the Intelli-Heat to be the guinea pig for them. Not sure if it would have made as much sense without the fairly decent discount over a cold-climate heat pump only. So far, at least for cooling it has been great but I am waiting for winter to see how it all works. Right now for me the economic cut-over for gas is somewhere in the mid-20s. I have configured the system (it is user adjustable) to cut over from heat pump at 27 degrees (you can unfortunately only set one of five pre-defined temperatures to lockout heat pump). I will say it is a *very* complex install and there are issues if you don't go with the Mitsubishi MHK2 thermostat. Mine is paired with a 97% Trane furnace.

Also one other thing. Since Mitsubishi cannot control what furnace it is paired with, they have to assume the worst so the efficiency ratings will look low but if you are pairing it with a modern variable speed furnace then you should see efficiency similar to what you'd get with a Mitsubishi air handler. But the lower ratings may impact your ability to get rebates.
dalbright
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Re: Heat pump sizing and brands?

Post by dalbright »

THY4373 wrote: Wed Jun 05, 2024 11:41 am
dalbright wrote: Wed Jun 05, 2024 4:07 am
Did you install the dual fuel intelli-heat? Or was this just the mitsubishi air handler? If you went the intell-heat route I would love to hear your thoughts on it as i've been leaning that way when my r-22 trane says its had enough someday (hopefully never).
I have a Mitsubishi Intelli-Heat installed for my downstairs system. Unfortunately it was installed after the heating season in late spring so no feedback on heating. So far I am happy with it. It replaced a 30-year old dual fuel heat pump/gas furnace system. My installer had done my upstairs system which is a heat pump only system and cut me a deal on the Intelli-Heat to be the guinea pig for them. Not sure if it would have made as much sense without the fairly decent discount over a cold-climate heat pump only. So far, at least for cooling it has been great but I am waiting for winter to see how it all works. Right now for me the economic cut-over for gas is somewhere in the mid-20s. I have configured the system (it is user adjustable) to cut over from heat pump at 27 degrees (you can unfortunately only set one of five pre-defined temperatures to lockout heat pump). I will say it is a *very* complex install and there are issues if you don't go with the Mitsubishi MHK2 thermostat. Mine is paired with a 97% Trane furnace.

Also one other thing. Since Mitsubishi cannot control what furnace it is paired with, they have to assume the worst so the efficiency ratings will look low but if you are pairing it with a modern variable speed furnace then you should see efficiency similar to what you'd get with a Mitsubishi air handler. But the lower ratings may impact your ability to get rebates.
Thanks for the info! I've installed pioneer mini-splits and a mitsubishi mini so far. A dual fuel intelli-heat is my current plan when the inevitable happens to the central unit (over 20yr old trane r22). Ironically the 2 pioneers were the "backup" but already lost one due to reversing valve failure so upgraded it to the mitsubishi for the next round. I read the manual for the intelli-heats cover to cover a few months back so that I would know what I was in for. Some of the reviews seemed mixed about it but it sounded like most was due to installers not reading the massive manual for it and not using the MHK2. Glad to hear you are having a good experience with yours so far. I'll primarily just use it for AC personally but enjoy the backup use for heat.
Hullmet
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Re: Heat pump sizing and brands?

Post by Hullmet »

NYCaviator wrote: Mon Jun 03, 2024 9:01 am We’re getting quoted for a cold weather ducted heat pump. I’m really confused about sizing and want to get some opinions before I have the contractors out so I am somewhat informed.

Size
The space we need to heat and cool is around 2,800 sqft. For traditional AC, the online estimators said 5 ton unit. I looked at Mitsubishis ducted options, but it only goes up to 42,000 BTU and says “up to 2k sqft”. Many US homes are over 2k sqft these days, so are people using two heat pumps or are the Mitsubishi units only for smaller homes?

I plan to have the contractors run a manual J (if they will) but I’d like to go in with some idea of what to expect so I know if they’re full of it. I don’t want an oversized or undersized unit.

Brands
Aside from Mitsubishi, there are a ton of heat pump brands I’ve never heard of. Trane/Carrier/Lennox have heat pumps but they are harder to find info on. I’m skeptical about using cheap brands like Goodman, Rheem, “Mr. Cool,” or the myriad brands no one has heard of. How do you know what’s good and what’s not?

Warranty
I was really impressed with the Bosch literature. We have Bosch appliances and have been very happy with durability so I trust the company. Their heat pumps have a 10 year warranty, which looks like it’s the longest in the business. Are their units any good? Any other units that have good warranties?

Getting a heat pump is filled with potential pitfalls and misinformation. Contractors make it even more difficult to figure out what’s true/what’s correct because most of them seem to want to push you into a traditional unit.
Bryant is very reputable. Do not go cheap on heat pumps
THY4373
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Re: Heat pump sizing and brands?

Post by THY4373 »

dalbright wrote: Wed Jun 05, 2024 12:05 pm
Thanks for the info! I've installed pioneer mini-splits and a mitsubishi mini so far. A dual fuel intelli-heat is my current plan when the inevitable happens to the central unit (over 20yr old trane r22). Ironically the 2 pioneers were the "backup" but already lost one due to reversing valve failure so upgraded it to the mitsubishi for the next round. I read the manual for the intelli-heats cover to cover a few months back so that I would know what I was in for. Some of the reviews seemed mixed about it but it sounded like most was due to installers not reading the massive manual for it and not using the MHK2. Glad to hear you are having a good experience with yours so far. I'll primarily just use it for AC personally but enjoy the backup use for heat.
I saw some of the same reviews on Reddit and it made me nervous but so far things have been fine. The only mistake my installers made (at least that I found so far) was not enabling high and low speed operation in the MHK2 so the furnace fan was always running high. I fixed that myself because like you I read the install manual front to back. I really like the Mitsubishi P series they are so quiet. I will say my electric usage is considerably lower now. My old unit was a 12 SEER and I'd guess it was well less than that by the time it was removed.
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NYCaviator
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Re: Heat pump sizing and brands?

Post by NYCaviator »

We ended up ordering a Mitsubishi system with a backup electric heater. I did a ton of research and was really leaning towards a gas backup system, but switched at the last minute. Based on my rough calculations, the heat pump won't cost too much more in the winter to run, even when it's really cold. Plus, the gas company is already proposing rate hikes, which I'm sure will continue to happen in the future.

For anyone going through this process, I'd urge you to find a local company that specializes in electrification or green energy. I got 6 quotes, and all of the traditional HVAC companies clearly didn't know much about heat pumps/didn't want to install them. All of them were pushing gas backups below 30 degrees and trying to convince me to just get traditional equipment instead. They were also saying how unreliable the heat pumps are and how traditional equipment is better. Their prices were also absurdly high.

They were also VERY misinformed about the local/state incentives. Two of the quotes came from companies that specialize in green energy/heat pumps and they were extremely transparent about the limitations/benefits of each recommended system, and ended up saving me over $10k with all of the rebates/incentives. A couple other traditional HVAC companies told me that these rebates didn't exist or were out of money so I shouldn't bother (which I found out was not true at all).

TL:DR, there's a LOT of misinformation out there about heat pumps, and many traditional HVAC companies don't want to sell them. Do your research and get quotes from green energy companies.
WhyNotUs
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Re: Heat pump sizing and brands?

Post by WhyNotUs »

NYCaviator wrote: Thu Jun 06, 2024 6:51 am TL:DR, there's a LOT of misinformation out there about heat pumps, and many traditional HVAC companies don't want to sell them. Do your research and get quotes from green energy companies.
Good advice.
I think you will be happy with your Mitsu choice. We have electric baseboard backup in mountains of CO. I did not use the baseboards this winter. Our utility has very low number and length of outages. The advantage of dual fuel comes in areas with regular outages or extended outages. I hope to ne using my electric car as my emergency backup in the not too distance future but will need to wait until the bugs get worked out on that.
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TravellingTechOnFire
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Re: Heat pump sizing and brands?

Post by TravellingTechOnFire »

NYCaviator wrote: Thu Jun 06, 2024 6:51 am We ended up ordering a Mitsubishi system with a backup electric heater. I did a ton of research and was really leaning towards a gas backup system, but switched at the last minute. Based on my rough calculations, the heat pump won't cost too much more in the winter to run, even when it's really cold. Plus, the gas company is already proposing rate hikes, which I'm sure will continue to happen in the future.

For anyone going through this process, I'd urge you to find a local company that specializes in electrification or green energy. I got 6 quotes, and all of the traditional HVAC companies clearly didn't know much about heat pumps/didn't want to install them. All of them were pushing gas backups below 30 degrees and trying to convince me to just get traditional equipment instead. They were also saying how unreliable the heat pumps are and how traditional equipment is better. Their prices were also absurdly high.

They were also VERY misinformed about the local/state incentives. Two of the quotes came from companies that specialize in green energy/heat pumps and they were extremely transparent about the limitations/benefits of each recommended system, and ended up saving me over $10k with all of the rebates/incentives. A couple other traditional HVAC companies told me that these rebates didn't exist or were out of money so I shouldn't bother (which I found out was not true at all).

TL:DR, there's a LOT of misinformation out there about heat pumps, and many traditional HVAC companies don't want to sell them. Do your research and get quotes from green energy companies.
Exellent update, thanks! AFAIK, the Mitsubishi heat pumps run rather efficiently down to about 4F, and will *work*(although not efficiently) down to -13F or so. For most areas of the US, this should work well.

Don't rule out solar if it's an option where you live(i.e. shade, roof configuration etc). During my research phase, I found solar as low as $2.30/watt before tax credit, or $1.61/watt after credit. Imagine 100% of you energy needs being fully covered by solar: electricity, heating, cooling, cars, etc. Quite a boon for retirement expenses! My energy needs are 100% covered by solar other than heat which is the last piece of the puzzle for me. Will be replacing a gas furnace with ducted(Mitsubishi?) heat pump hopefully next year.
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Re: Heat pump sizing and brands?

Post by NYCaviator »

WhyNotUs wrote: Thu Jun 06, 2024 2:38 pm
NYCaviator wrote: Thu Jun 06, 2024 6:51 am TL:DR, there's a LOT of misinformation out there about heat pumps, and many traditional HVAC companies don't want to sell them. Do your research and get quotes from green energy companies.
Good advice.
I think you will be happy with your Mitsu choice. We have electric baseboard backup in mountains of CO. I did not use the baseboards this winter. Our utility has very low number and length of outages. The advantage of dual fuel comes in areas with regular outages or extended outages. I hope to ne using my electric car as my emergency backup in the not too distance future but will need to wait until the bugs get worked out on that.
We still have a gas fireplace which could be used in a pinch. If we had a power outage, our old gas furnace wouldn't work either because of the thermostat :D Thankfully we have reliable power.
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Re: Heat pump sizing and brands?

Post by NYCaviator »

TravellingTechOnFire wrote: Thu Jun 06, 2024 2:59 pm
Exellent update, thanks! AFAIK, the Mitsubishi heat pumps run rather efficiently down to about 4F, and will *work*(although not efficiently) down to -13F or so. For most areas of the US, this should work well.

Don't rule out solar if it's an option where you live(i.e. shade, roof configuration etc). During my research phase, I found solar as low as $2.30/watt before tax credit, or $1.61/watt after credit. Imagine 100% of you energy needs being fully covered by solar: electricity, heating, cooling, cars, etc. Quite a boon for retirement expenses! My energy needs are 100% covered by solar other than heat which is the last piece of the puzzle for me. Will be replacing a gas furnace with ducted(Mitsubishi?) heat pump hopefully next year.
We are getting the backup heat strips installed "just in case" but I know they'll cost a fortune to run. We are looking at solar, but (much like heat pumps) there are a lot of shady companies out there.
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Re: Heat pump sizing and brands?

Post by Valuethinker »

NYCaviator wrote: Thu Jun 06, 2024 6:51 am We ended up ordering a Mitsubishi system with a backup electric heater. I did a ton of research and was really leaning towards a gas backup system, but switched at the last minute. Based on my rough calculations, the heat pump won't cost too much more in the winter to run, even when it's really cold. Plus, the gas company is already proposing rate hikes, which I'm sure will continue to happen in the future.
Is it not also the case that if you disconnect from gas, entirely, you save yourself a fixed monthly charge? (I realise different localities have different rules).
For anyone going through this process, I'd urge you to find a local company that specializes in electrification or green energy. I got 6 quotes, and all of the traditional HVAC companies clearly didn't know much about heat pumps/didn't want to install them. All of them were pushing gas backups below 30 degrees and trying to convince me to just get traditional equipment instead. They were also saying how unreliable the heat pumps are and how traditional equipment is better. Their prices were also absurdly high.

They were also VERY misinformed about the local/state incentives. Two of the quotes came from companies that specialize in green energy/heat pumps and they were extremely transparent about the limitations/benefits of each recommended system, and ended up saving me over $10k with all of the rebates/incentives. A couple other traditional HVAC companies told me that these rebates didn't exist or were out of money so I shouldn't bother (which I found out was not true at all).

TL:DR, there's a LOT of misinformation out there about heat pumps, and many traditional HVAC companies don't want to sell them. Do your research and get quotes from green energy companies.
Consistent with what others have said.

North America really isn't a heat pump market (for heating) and the expertise is just not there.
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Re: Heat pump sizing and brands?

Post by nisiprius »

Alert, dumb remarks ahead.

We replaced a monster 108-pound window A/C that cooled two big rooms, with a mini-split. The HVAC contractor gave us quotes for Mitsubishi and Samsung. Samsung was noticeably cheaper. As we were thinking it over, we happened to look at the contractor's truck. It had a big Mitsubishi logo on it, as big as their own (big) logo.

It did not say Samsung on it anywhere.

We shrugged, and joined that together with other vague observations (like seeing dozens of Mitsubishi compressors everywhere in our neighborhood and not a single Samsung) and figured... hey, buy the super-dominant brand for safety. Might be overpaying. Everything in Mitsubishi's lineup might not be great. Maybe Mitsubishi pays contractors to put their logo on their trucks. I dunno. After installation we turned it on to "cool" and cold air came out, and we turned it on to "heat" and hot air came out, so... so far so good.
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Re: Heat pump sizing and brands?

Post by Valuethinker »

nisiprius wrote: Fri Jun 07, 2024 8:29 am Alert, dumb remarks ahead.

We replaced a monster 108-pound window A/C that cooled two big rooms, with a mini-split. The HVAC contractor gave us quotes for Mitsubishi and Samsung. Samsung was noticeably cheaper. As we were thinking it over, we happened to look at the contractor's truck. It had a big Mitsubishi logo on it, as big as their own (big) logo.

It did not say Samsung on it anywhere.

We shrugged, and joined that together with other vague observations (like seeing dozens of Mitsubishi compressors everywhere in our neighborhood and not a single Samsung) and figured... hey, buy the super-dominant brand for safety. Might be overpaying. Everything in Mitsubishi's lineup might not be great. Maybe Mitsubishi pays contractors to put their logo on their trucks. I dunno. After installation we turned it on to "cool" and cold air came out, and we turned it on to "heat" and hot air came out, so... so far so good.
Korean appliance manufacturers have a problem.

What I have been told, from several sources, that you cannot get the spare parts. Very poor service infrastructure.

Another thread here suggested this was Samsung but not LG? I think? I am not sure what I heard has distinguished between them. Just a general warning not to buy Korean appliances. (The way Hyundai (and Kia?) have treated customers over the problem with the security system - is not exactly reassuring).

Infamous tale of Japanese manufacturer in the 1980s - ball bearings. US company ordered from them, and contract specified an error rate of (say 1/10000). They received the 3 million ball bearings. But along came a separate shipment, of 300 ball bearings, with an attached note "We are unsure as to why you specified 300 ball bearings with flaws in them, but we thought we had better segregate them out in returning your order ..."

(I think they used this case study at the Harvard Business School, at least the person who told it to me had been to HBS and then worked for McKinsey).

So, in the absence of alternative information, I would bet the Japanese make reliable heat pumps. Because it's a huge domestic market for them, and their domestic market is highly quality-led (in just about anything).
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Re: Heat pump sizing and brands?

Post by Ricola »

Also, I have been hearing a lot about heat pumps. Don't they run more often and use more electricity? If you are in a hot summer climate area (100+) with a cost of 50 cents KWH are they still a viable option?
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Re: Heat pump sizing and brands?

Post by NYCaviator »

Ricola wrote: Sat Jun 08, 2024 11:18 am Also, I have been hearing a lot about heat pumps. Don't they run more often and use more electricity? If you are in a hot summer climate area (100+) with a cost of 50 cents KWH are they still a viable option?
A heat pump is basically an A/C untit that can work both ways (heat and cool) so it'll be just as efficient - if not more efficient - at cooling than a traditional A/C.

My understanding is that one huge benefit of having it run constantly is that you get a more even temp throughout the house. Rather than spikes and dips, you maintain your set temp throughout the day. Traditional A/C waits until the thermostat hits a certain threshold and then blasts the house with cold air and then turns off once it cools off. The house heats up, the A/C hits the set point again, blasts cold air, and then turns off. Over and over again. So it's the constantly cycling that actually uses more energy than having the unit maintain a steady temp with a lower workload. I think you can achieve the same thing with a variable blower traditional A/C.
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Re: Heat pump sizing and brands?

Post by Ricola »

NYCaviator wrote: Sat Jun 08, 2024 1:51 pm
Ricola wrote: Sat Jun 08, 2024 11:18 am Also, I have been hearing a lot about heat pumps. Don't they run more often and use more electricity? If you are in a hot summer climate area (100+) with a cost of 50 cents KWH are they still a viable option?
A heat pump is basically an A/C untit that can work both ways (heat and cool) so it'll be just as efficient - if not more efficient - at cooling than a traditional A/C.

My understanding is that one huge benefit of having it run constantly is that you get a more even temp throughout the house. Rather than spikes and dips, you maintain your set temp throughout the day. Traditional A/C waits until the thermostat hits a certain threshold and then blasts the house with cold air and then turns off once it cools off. The house heats up, the A/C hits the set point again, blasts cold air, and then turns off. Over and over again. So it's the constantly cycling that actually uses more energy than having the unit maintain a steady temp with a lower workload. I think you can achieve the same thing with a variable blower traditional A/C.
Thanks for the explanation. I have only seen these as separate one-room type systems, but from some of the early comments it appears they can be adapted to an existing HVAC that is ducted to all rooms.
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Re: Heat pump sizing and brands?

Post by TravellingTechOnFire »

NYCaviator wrote: Fri Jun 07, 2024 7:34 am
TravellingTechOnFire wrote: Thu Jun 06, 2024 2:59 pm
Exellent update, thanks! AFAIK, the Mitsubishi heat pumps run rather efficiently down to about 4F, and will *work*(although not efficiently) down to -13F or so. For most areas of the US, this should work well.

Don't rule out solar if it's an option where you live(i.e. shade, roof configuration etc). During my research phase, I found solar as low as $2.30/watt before tax credit, or $1.61/watt after credit. Imagine 100% of you energy needs being fully covered by solar: electricity, heating, cooling, cars, etc. Quite a boon for retirement expenses! My energy needs are 100% covered by solar other than heat which is the last piece of the puzzle for me. Will be replacing a gas furnace with ducted(Mitsubishi?) heat pump hopefully next year.
We are getting the backup heat strips installed "just in case" but I know they'll cost a fortune to run. We are looking at solar, but (much like heat pumps) there are a lot of shady companies out there.
For sure look for a reputable company, but equally or more important, go with materials that have the longest manufacturer warranty. That way, even if the installer is out of business in a decade or two, the parts are still covered.

I went with micro-inverters rather than one large string inverter for this reason. 25 year manufacturer warranty vs 10. Same with panels. If one fails, the rest of the system keeps working...replace the failed inverter at your leisure.
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Re: Heat pump sizing and brands?

Post by Northern Flicker »

I've heard but have not fully verified that Carrier heat pumps are now rebadged heat pumps made by a Chinese HVAC company that Carrier acquired. That wouldn't by itself imply that they are in any way inferior, but it would mean that any past reliability data for Carrier heat pumps would not apply.

Daikin, the largest heat pump manufacturer globally, currently owns Goodman.

Proper sizing for cooling will consider both square footage and duct flow rates. Not generally an issue with newer construction houses, but houses that were not designed with A/C in mind may not have the duct capacity for the size A/C that specs out per square footage. Some HVAC contractors will just spec the system by square footage, and will offer to sell a (more expensive) unit that overspecs the ducts.
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Re: Heat pump sizing and brands?

Post by Valuethinker »

Ricola wrote: Sat Jun 08, 2024 11:18 am Also, I have been hearing a lot about heat pumps. Don't they run more often and use more electricity? If you are in a hot summer climate area (100+) with a cost of 50 cents KWH are they still a viable option?
OK

1. Your air conditioner is a heat pump. Or rather, a heat pump also runs as an AC - it's just the HP can also run in reverse (cooling the outside, even in winter, and heating the inside).

So if you can afford to run AC in your climate, you can afford to run your HP. What matters is the SEER (I think now the SEER2) the "Seasonal Energy Efficiency Ratio")

https://www.townsendtotalenergy.com/seer-rating

That's what matters for cooling. As with all Heat Pumps (or ACs) the bigger the gap between external and internal temperatures the harder it has to work.

So much of AC is about humidity control. So simpler ACs which are single-speed often don't provide a good level of comfort. They cycle on and off too much-- you are either too warm or too cold. Newer systems use inverters and can vary their speed which provides a greater level of comfort.

2. for heating with a HP, we have Coefficient of Performance (Seasonal Coefficient of Performance). That measures how many kwhr of heat you move (to heat your home) per kwhr of electricity. Just for comparison, a high efficiency gas furnace would have one of about 0.95 -- but of course gas is usually a lot cheaper than electricity.

3.0 is deemed "good". Some of the Japanese ones get over 4.0 -- because of the extremes of heat and cold in Japan, they have worked to improve performance. This does, as always depend on how cold it is outside. Historically when temperatures got much below say 32 F, the COP would fall close to 1.0 - ie the efficiency of the electric strip backup, or you would switch to gas heat. Now, however, you can get good performance down to (I think?) low 10s of F.

The US HP market has historically been very much in the South -- the humid South in particular. Thus cooling focused, with limited loads on winter heat. So US manufacturers are behind.

Because it's the "delta", ie the gap, between input and output temperatures, HPs run best "low and slow" rather than "hot and fast" as one does with a gas furnace. That means you don't get the same blasts of hot air out of the system, but the room will still get to the same temperature. On a cold winter day, they will run most or all of the time.

So to answer your question would a heat pump work in a hot summer climate, over 100 F, 50c / kwhr electricity?

For cooling, it would work as well as an equivalently efficient air conditioning system. A key is to get 2 speed or variable speed technology, because you are more likely to be comfortable (even at a higher interior temperature).

For heating, it depends. But most places that get that hot in summer, don't get that cold in winter (I am thinking California, because electricity prices in Texas, say, are much lower?). So it should work fine. If natural gas is cheap, they won't necessarily be any saving over a gas furnace.

Interestingly heat pumps are being installed a lot in Maine. Partly due to a state subsidy, I think. But Maine can have very hot summers, and certainly has cold winters. Natural gas is expensive in Maine, if indeed available at all in many communities. But so is electricity. So likely this is displacing oil and propane heat. But clearly they do work.
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Re: Heat pump sizing and brands?

Post by NYCaviator »

Northern Flicker wrote: Sat Jun 08, 2024 3:06 pm I've heard but have not fully verified that Carrier heat pumps are now rebadged heat pumps made by a Chinese HVAC company that Carrier acquired. That wouldn't by itself imply that they are in any way inferior, but it would mean that any past reliability data for Carrier heat pumps would not apply.
We got quotes on the Carrier heat pumps and they were REALLY expensive. The higher end cold climate ones were almost double the cost of the Mitsubishi units that everyone raves about. The installer was also pushing the "dual fuel" option with carrier as well saying that it loses a lot of efficiency below 30 degrees, so you really need a gas backup.

They have some mid-range and cheaper models that were still more expensive than the Mitsubishi but were not cold climate rated, thus you needed a gas backup for our weather.
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Re: Heat pump sizing and brands?

Post by THY4373 »

Northern Flicker wrote: Sat Jun 08, 2024 3:06 pm I've heard but have not fully verified that Carrier heat pumps are now rebadged heat pumps made by a Chinese HVAC company that Carrier acquired. That wouldn't by itself imply that they are in any way inferior, but it would mean that any past reliability data for Carrier heat pumps would not apply.
Carrier does sell rebadged equipment manufactured by Midea in China but still sells Carrier made stuff as well. Also I don't believe Carrier owns Midea.
Last edited by THY4373 on Sat Jun 08, 2024 4:58 pm, edited 2 times in total.
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Re: Heat pump sizing and brands?

Post by THY4373 »

nisiprius wrote: Fri Jun 07, 2024 8:29 am We shrugged, and joined that together with other vague observations (like seeing dozens of Mitsubishi compressors everywhere in our neighborhood and not a single Samsung) and figured... hey, buy the super-dominant brand for safety.
I pretty much went with Mitsubishi for the same reason. I decided I wanted a high quality Asian made inverter heat pump (the rest of the world has been using this tech for many more years than we have and hopefully have the technology down). I did research and in my smaller city Mitsubishi seemed the best supported of the Japanese manufacturers (Daikin and Fujitsu were the other two brands I was considering). So far I have been very impressed with silence and energy savings of the Mitsubishi (SEER 20) over the SEER 10/12 units they replaced.
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Re: Heat pump sizing and brands?

Post by Northern Flicker »

NYCaviator wrote: Sat Jun 08, 2024 1:51 pm
Ricola wrote: Sat Jun 08, 2024 11:18 am Also, I have been hearing a lot about heat pumps. Don't they run more often and use more electricity? If you are in a hot summer climate area (100+) with a cost of 50 cents KWH are they still a viable option?
A heat pump is basically an A/C unit that can work both ways (heat and cool) so it'll be just as efficient - if not more efficient - at cooling than a traditional A/C.
Our Daikin heat pump is available as an A/C or as a heat pump. The A/C version is the same unit as the heat pump, but without the reversing valve. SEER and SEER2 ratings for heat pumps (and A/Cs) are ratings of cooling efficiency. I'm not sure how much the SEER/SEER2 ratings indicate anything for heating efficiency. Heating efficiency varies significantly with outside temperature, at least with air sourced heat pumps.

I think the lowest SEER rated cooling unit that can be installed per regulation is around 13 in some parts of the country and around 14 in other parts of the country. I'm not sure what the minimums are expressed for SEER2.
Valuethinker
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Re: Heat pump sizing and brands?

Post by Valuethinker »

Northern Flicker wrote: Sun Jun 09, 2024 3:25 am
NYCaviator wrote: Sat Jun 08, 2024 1:51 pm
Ricola wrote: Sat Jun 08, 2024 11:18 am Also, I have been hearing a lot about heat pumps. Don't they run more often and use more electricity? If you are in a hot summer climate area (100+) with a cost of 50 cents KWH are they still a viable option?
A heat pump is basically an A/C unit that can work both ways (heat and cool) so it'll be just as efficient - if not more efficient - at cooling than a traditional A/C.
Our Daikin heat pump is available as an A/C or as a heat pump. The A/C version is the same unit as the heat pump, but without the reversing valve. SEER and SEER2 ratings for heat pumps (and A/Cs) are ratings of cooling efficiency. I'm not sure how much the SEER/SEER2 ratings indicate anything for heating efficiency. Heating efficiency varies significantly with outside temperature, at least with air sourced heat pumps.

I think the lowest SEER rated cooling unit that can be installed per regulation is around 13 in some parts of the country and around 14 in other parts of the country. I'm not sure what the minimums are expressed for SEER2.

For heating you want Coefficient of Performance (COP) or Seasonal COP. 3.0 means 1 kwhr ectricity gives you 3 kwhr heat.

Roughly speaking 3.0 is good. But some of these Japanese run well over 4.0.

I am not sure what external air temp that is measured on but I understand whereas once the COP got down towards 1.0 below 32F, now that's close to 0 F on better performing units.

Main thing is you won't get a blast of 90 F air out of your ducts. So you run the HP "low & slow" to keep that 70F temperature. Ie run it most of the time.

US domestic gas prices tend to be low, outside of New England, so the economics of HPs may not be as advantageous. OTOH recent work underlines the hazards of gas cooking due to internal air pollution and of course there is external air pollution from a gas furnace. And gas is explosive. So disconnection ftom gas network may be no bad thing.
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Re: Heat pump sizing and brands?

Post by talzara »

Northern Flicker wrote: Sat Jun 08, 2024 3:06 pm I've heard but have not fully verified that Carrier heat pumps are now rebadged heat pumps made by a Chinese HVAC company that Carrier acquired. That wouldn't by itself imply that they are in any way inferior, but it would mean that any past reliability data for Carrier heat pumps would not apply.

Daikin, the largest heat pump manufacturer globally, currently owns Goodman.
THY4373 wrote: Sat Jun 08, 2024 4:50 pm Carrier does sell rebadged equipment manufactured by Midea in China but still sells Carrier made stuff as well. Also I don't believe Carrier owns Midea.
Carrier does not own Midea. It owns part of the Carrier Midea joint venture, and it has a minority stake in a Midea subsidiary. Carrier also owns a controlling stake in Giwee, a smaller Chinese HVAC manufacturer that makes Chigo mini-splits. Chigo is one of the few mini-split brands available to HVAC DIYers that's not made by Midea or Gree.

Carrier-branded mini-splits are manufactured by Midea in a joint venture. They're not rebadged Chigos.

None of the major American HVAC manufacturers makes its own mini-splits. Trane mini-splits are manufactured by Mitsubishi in a joint venture. Goodman mini-splits are manufactured by its parent company Daikin. Lennox, Rheem, and the other brands are all rebadging Asian mini-splits. If it looks like an Asian mini-split, then it is an Asian mini-split.

Daikin is the world's largest HVAC manufacturer. Midea is the second largest.
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hand
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Re: Heat pump sizing and brands?

Post by hand »

NYCaviator wrote: Sat Jun 08, 2024 1:51 pm
My understanding is that one huge benefit of having it run constantly is that you get a more even temp throughout the house. Rather than spikes and dips, you maintain your set temp throughout the day. Traditional A/C waits until the thermostat hits a certain threshold and then blasts the house with cold air and then turns off once it cools off. The house heats up, the A/C hits the set point again, blasts cold air, and then turns off. Over and over again. So it's the constantly cycling that actually uses more energy than having the unit maintain a steady temp with a lower workload. I think you can achieve the same thing with a variable blower traditional A/C.
The benefit of increased comfort due to extended run times is related to properly sizing the unit, rather than the underlying technology.

Oversized units that are unable to produce "low and slow" temperature changes oscillate between too high and off - which can be uncomfortable when they run, lead to pockets of uneven temperature when they aren't running, fail to dehumidify when they aren't running, and are harder on the equipment (starting creates much more wear and tear than steady state operations).

It is such a waste that both consumers and installers focus max cooling (how quickly the house cools and ability to keep the house at max cool on the absolute hottest of days) and massively oversize heating and cooling units when 95+% of the time, comfort would be improved with a smaller unit that kept the house evenly cooled and better managed humidity.

I forced my contractor to downsize by a ton, and unit still does not run anywhere near 100% on the hottest days.
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Re: Heat pump sizing and brands?

Post by clutchied »

NYCaviator wrote: Mon Jun 03, 2024 9:01 am We’re getting quoted for a cold weather ducted heat pump. I’m really confused about sizing and want to get some opinions before I have the contractors out so I am somewhat informed.

Size
The space we need to heat and cool is around 2,800 sqft. For traditional AC, the online estimators said 5 ton unit. I looked at Mitsubishis ducted options, but it only goes up to 42,000 BTU and says “up to 2k sqft”. Many US homes are over 2k sqft these days, so are people using two heat pumps or are the Mitsubishi units only for smaller homes?

I plan to have the contractors run a manual J (if they will) but I’d like to go in with some idea of what to expect so I know if they’re full of it. I don’t want an oversized or undersized unit.

Brands
Aside from Mitsubishi, there are a ton of heat pump brands I’ve never heard of. Trane/Carrier/Lennox have heat pumps but they are harder to find info on. I’m skeptical about using cheap brands like Goodman, Rheem, “Mr. Cool,” or the myriad brands no one has heard of. How do you know what’s good and what’s not?

Warranty
I was really impressed with the Bosch literature. We have Bosch appliances and have been very happy with durability so I trust the company. Their heat pumps have a 10 year warranty, which looks like it’s the longest in the business. Are their units any good? Any other units that have good warranties?

Getting a heat pump is filled with potential pitfalls and misinformation. Contractors make it even more difficult to figure out what’s true/what’s correct because most of them seem to want to push you into a traditional unit.

There are different types:

You have traditional heatpumps which are just the regular A/C units which can run in reverse. They have single and 2 stage units usually.

Then there are "swing inverter" heat pumps which don't use a traditional scroll compressor. These are those flat side discharge units you see around. Think minisplit. The are basically modulating A/C units that aren't just on or off or working at a lower level like a 2stage. These are infinitely variable and only provide the heating and cooling required and can adjust super fast to changes.

The Daikin Fit and Amana S series are whole house units that use this technology.

THEN: you can also have a hybrid heatpump/furnace setup to use the HP during the summer and shoulder seasons and the furnace when it drops past a user defined set point. This is where I am currently headed as it makes the most sense for our location (Midwest). If it's just a heatpump you would have an "air handler" instead of the furnace to house your blower and coil. They also usually have an emergency electric heat setting incase it drops past the point where the heatpump can work. You see these in the south where it doesn't get all that cold.

Some people will tell you a HP can go WAY down to like -22F and they can but they burn tons of electricity to ring the last bits out of the air and for me that just seems silly. I would never go heatpump only Ohio and North. You put yourself at the mercy of A/C rates with no diverse fuel options.
z0r
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Re: Heat pump sizing and brands?

Post by z0r »

there is little to no real-world research that indicates there is either an energy penalty or a humidity control penalty for oversizing

I might eventually write a longer post on this but if you want some threads to pull on you can start with this:

https://bergeronmechanicalsystems.com/w ... ings-1.pdf

which will lead to papers like this:

https://www.fsec.ucf.edu/en/publication ... 641-06.pdf

with quotes like this:

"Potential energy savings from current generation [2006] right-sized machines may average 2-3% for systems with sealed duct systems with the ducts located within the conditioned space"

the main reasons are:
1. humidity control (if you choose not to install a dehumidifier to address the problem directly) is relative to airflow and coil size. a larger unit will scale both of these up and will accomplish the same average humidity control (in bursts rather than over time). improved humidity control can come from running lower airflow vs. the coil size, which any unit can do. if you really want humidity control at the expense of other factors, one trick is to actually oversize your equipment slightly and choose a lower airflow (or keep the same airflow you had)
2. manufacturers have been pushed to reduce cycling losses in ALL equipment, even dumb single stage stuff. cycling losses are now extremely low. "conventional wisdom" about cycling losses must have arisen before this happened. as of 2009 cycling losses were already on the order of 3.5%. as SEER requirements have gone up this is one of the main areas that has improved
3. if any of your ducts are not in conditioned space, then duct losses are roughly proportional to runtime. smaller equipment will run longer and will have bigger duct losses, and it doesn't take much to offset the win from reducing that 3.5% cycling penalty

I will point out that, if you aren't touching your ductwork, it has a certain capacity. it's IS pretty important not to oversize your equipment relative to your ductwork, for a few reasons
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hand
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Re: Heat pump sizing and brands?

Post by hand »

z0r wrote: Mon Jun 10, 2024 1:17 pm there is little to no real-world research that indicates there is either an energy penalty or a humidity control penalty for oversizing

I might eventually write a longer post on this but if you want some threads to pull on you can start with this:

https://bergeronmechanicalsystems.com/w ... ings-1.pdf

which will lead to papers like this:

https://www.fsec.ucf.edu/en/publication ... 641-06.pdf

with quotes like this:

"Potential energy savings from current generation [2006] right-sized machines may average 2-3% for systems with sealed duct systems with the ducts located within the conditioned space"
Super interesting - thank you!
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Re: Heat pump sizing and brands?

Post by alfaspider »

NYCaviator wrote: Sat Jun 08, 2024 4:35 pm
Northern Flicker wrote: Sat Jun 08, 2024 3:06 pm I've heard but have not fully verified that Carrier heat pumps are now rebadged heat pumps made by a Chinese HVAC company that Carrier acquired. That wouldn't by itself imply that they are in any way inferior, but it would mean that any past reliability data for Carrier heat pumps would not apply.
We got quotes on the Carrier heat pumps and they were REALLY expensive. The higher end cold climate ones were almost double the cost of the Mitsubishi units that everyone raves about. The installer was also pushing the "dual fuel" option with carrier as well saying that it loses a lot of efficiency below 30 degrees, so you really need a gas backup.

They have some mid-range and cheaper models that were still more expensive than the Mitsubishi but were not cold climate rated, thus you needed a gas backup for our weather.
This is more of a problem with Carrier's dealer network than the units themselves. They are like car salespeople. I bought my Carrier heat pump grey market, and the installed cost was roughly 1/2 of what authorized dealers charged.

The "dual fuel" option is really more of a sales job than a necessity. The higher-end units don't need a gas backup for cold weather. The only reason why you might want it is optionality if the price of electricity or natural gas changes dramatically.
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Re: Heat pump sizing and brands?

Post by NYCaviator »

alfaspider wrote: Mon Jun 10, 2024 2:21 pm
This is more of a problem with Carrier's dealer network than the units themselves. They are like car salespeople. I bought my Carrier heat pump grey market, and the installed cost was roughly 1/2 of what authorized dealers charged.
Don't you forfeit the warranty at that point then?
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Re: Heat pump sizing and brands?

Post by Legoman666 »

We replaced our 18 year old heat pump in northern Kentucky with a seven zone mini split system from Mitsubishi. It's awesome. Due to the high install costs (snaking 7 refrigerant lines through walls and attic is no joke), we did it in 2 batches: 4 in October 22, then 3 more in April 23. Total cost was $31k, although that included a heat pump water heater and a steam humidifier too.

The system is awesome. We love being able to control each room individually, especially our bedroom. The kitchen/living room used to be baking hot late in the afternoon from the sun blasting through the SW facing windows. Now it's always 75. We had a diamond contractor do the work, so we get a 12 yr warranty.

We keep our house cooler in the summer and warmer in the winter than we did with the old system and yet our electric bills are 30-40% less than before.

The coil in the old central system has been removed and we had a quiet fan installed. It runs the backup heat and the humidifier.
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Re: Heat pump sizing and brands?

Post by talzara »

clutchied wrote: Mon Jun 10, 2024 12:43 pm Then there are "swing inverter" heat pumps which don't use a traditional scroll compressor. These are those flat side discharge units you see around. Think minisplit. The are basically modulating A/C units that aren't just on or off or working at a lower level like a 2stage. These are infinitely variable and only provide the heating and cooling required and can adjust super fast to changes.

The Daikin Fit and Amana S series are whole house units that use this technology.
Daikin is the only major manufacturer that uses swing compressors. Other mini-split manufacturers use scroll compressors.

The Amana S series is made by Daikin.
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Re: Heat pump sizing and brands?

Post by vnatale »

I have about a 900 square foot house.

I got quotes from at least 12 different contractors. I'm quite thorough in getting multi-quotes as it also serves as an educational process for me.

I narrowed it down to 4 contractors, all of which were selling Mitsubishi (I am in Massachusetts). That made it easy to compare the quotes.

I ended up going with a 6,000 BTU for each of the bedrooms and a 15,000 BTU for the living room which was to heat all the way to the kitchen. I just checked as the 15,000 did not seem correct. It was 18,000. I asked the contractor why he recommended one that large (as others were recommending smaller ones). He said while it would not be as efficient in terms of electricity usage as a smaller one it'd better be able to handle the lower temperatures.

For all of that my cost was $16,500 with a rebate of $16,000 from the electric company. So, my net cost was only $500.

Since I can't stand air conditioning I've only used them for heat. I went live with them on December 30, 2022. My oil furnace was turned off that date and has never been turned back on.
Above provided by: Vinny, who always says: "I only regret that I have but one lap to give to my cats." AND "I'm a more-is-more person."
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Re: Heat pump sizing and brands?

Post by alfaspider »

NYCaviator wrote: Mon Jun 10, 2024 6:26 pm
alfaspider wrote: Mon Jun 10, 2024 2:21 pm
This is more of a problem with Carrier's dealer network than the units themselves. They are like car salespeople. I bought my Carrier heat pump grey market, and the installed cost was roughly 1/2 of what authorized dealers charged.
Don't you forfeit the warranty at that point then?
Yes, but at 50% price, I could pay for a LOT of warranty repairs. The grey market company also offered its own warranty, though who knows if it's worth anything. Most properly installed systems shouldn't need warranty work.
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Re: Heat pump sizing and brands?

Post by NYCaviator »

alfaspider wrote: Tue Jun 11, 2024 7:56 am
NYCaviator wrote: Mon Jun 10, 2024 6:26 pm
alfaspider wrote: Mon Jun 10, 2024 2:21 pm
This is more of a problem with Carrier's dealer network than the units themselves. They are like car salespeople. I bought my Carrier heat pump grey market, and the installed cost was roughly 1/2 of what authorized dealers charged.
Don't you forfeit the warranty at that point then?
Yes, but at 50% price, I could pay for a LOT of warranty repairs. The grey market company also offered its own warranty, though who knows if it's worth anything. Most properly installed systems shouldn't need warranty work.
We went with a company that handled all of the rebates for us up front, so they are baked into my net price. I don't have to deal with paperwork or anything like that. It ended up being substantially cheaper than a traditional system due to all of the incentives for people switching to heat pumps.
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Re: Heat pump sizing and brands?

Post by Northern Flicker »

alfaspider wrote: Tue Jun 11, 2024 7:56 am
NYCaviator wrote: Mon Jun 10, 2024 6:26 pm
alfaspider wrote: Mon Jun 10, 2024 2:21 pm
This is more of a problem with Carrier's dealer network than the units themselves. They are like car salespeople. I bought my Carrier heat pump grey market, and the installed cost was roughly 1/2 of what authorized dealers charged.
Don't you forfeit the warranty at that point then?
Yes, but at 50% price, I could pay for a LOT of warranty repairs. The grey market company also offered its own warranty, though who knows if it's worth anything. Most properly installed systems shouldn't need warranty work.
Our installer informed us that a reversing valve failure is the most common warranty repair on a heat pump, and not terribly uncommon. If it locks up, the HP will stay in whichever mode (cooling vs heating) it was in when the lockup happened. Some of the warranties will cover parts or labor but not both.
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Re: Heat pump sizing and brands?

Post by suemarkp »

And to change out a $100 reversing valve requires the refrigerant be evacuated and refilled. Most warranties don't cover that (some may on a compressor fail, but many still don't cover that on warranties). The refrigerant evac/refill can take a $200 service call that might have been free under warranty to over $1000 that isn't covered.

Can you tell I'm bitter against heat pumps and HVAC companies. I had that reversing valve failure happen twice.
Mark | Somewhere in WA State
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