Hybrid Water Heater

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btenny
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Hybrid Water Heater

Post by btenny »

I live in Phoenix and am thinking about changing out my electric storage water heater for a new hybrid heat pump water heater type. I want to make some changes for multiple reasons but need some advice on the costs and issues and what exactly to do.

1. My garage is very hot and needs some type of cooling to keep my cars cool over the summer.
2. My current water heater is 14 or so years old but still works.
3. My electric bill is low in the summer as we turn off the water heater and turn up the AC.
4. The garage ceiling is insulated but the walls are cement block with no insulation.
5. The garage door is metal with no insulation.

So my current plan is to put in the new HP water heater and let it cool my garage when I am home. I will leave it running on a low setting when I leave for parts of the summer as well. I plan to put some foam insulation in the garage door.

Who has put in a HPWH? What were the costs? For the heater? Where and how did you buy it? What size did you buy? 50 gallon or 65 gallon? Why? What did you pay to get it installed? How did you get the HPWH delivered? How did you get the old WH taken away?

How well will this HPWH cool the garage when we are home and using water?

How well will this HPWH cool the garage if the HPWH is set on a low setting and the water is not used?

Who has put rigid foam insulation in their garage door? Did you hire it done? Did you do it yourself? Costs?

Other issues? Please advise. Thanks in advance for any thoughts you have.
Smoke
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Re: Hybrid Water Heater

Post by Smoke »

btenny wrote: Thu Jul 04, 2019 4:57 pm I live in Phoenix and am thinking about changing out my electric storage water heater for a new hybrid heat pump water heater type. I want to make some changes for multiple reasons but need some advice on the costs and issues and what exactly to do.

1. My garage is very hot and needs some type of cooling to keep my cars cool over the summer.
2. My current water heater is 14 or so years old but still works.
3. My electric bill is low in the summer as we turn off the water heater and turn up the AC.
4. The garage ceiling is insulated but the walls are cement block with no insulation.
5. The garage door is metal with no insulation.

So my current plan is to put in the new HP water heater and let it cool my garage when I am home. I will leave it running on a low setting when I leave for parts of the summer as well. I plan to put some foam insulation in the garage door.

Who has put in a HPWH? What were the costs? For the heater? Where and how did you buy it? What size did you buy? 50 gallon or 65 gallon? Why? What did you pay to get it installed? How did you get the HPWH delivered? How did you get the old WH taken away?

Check out Lowes or Home depot to get ideas on cost size and installation.

How well will this HPWH cool the garage when we are home and using water?

Probably not much, if the garage is that hot the WH will not run for long, incoming water is most likely very warm as well.

How well will this HPWH cool the garage if the HPWH is set on a low setting and the water is not used?

Not at all, if it is not heating the water it's not running or cooling.

Who has put rigid foam insulation in their garage door? Did you hire it done? Did you do it yourself? Costs?

Mine came installed with foam attached. They used to make a insulating blanket that attached to the inside of Garage doors, check amazon for types.

Other issues? Please advise. Thanks in advance for any thoughts you have.

Installing insulation alone will not help with the buildup of heat in a sealed garage. Insulation just slows down the transfer of heat but eventually will get into an unconditioned space and heat up.
You could try ventilation, or install an actual a/c unit or swamp cooler with insulating.

Arguing for the sake of arguing is something I am not going to engage in.
adamthesmythe
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Re: Hybrid Water Heater

Post by adamthesmythe »

I said something incorrect on a previous thread. I have thought about this some and I think I have it right this time.

I assume the heat exchanger is located in the garage. The only way you get your garage cooler is if you remove hot water from the garage. Then the heat exchanger runs and removes more heat from the garage.

If you stop using hot water- I think there will be a slight amount of net heat buildup in the garage.
jminv
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Re: Hybrid Water Heater

Post by jminv »

btenny wrote: Thu Jul 04, 2019 4:57 pm I live in Phoenix and am thinking about changing out my electric storage water heater for a new hybrid heat pump water heater type. I want to make some changes for multiple reasons but need some advice on the costs and issues and what exactly to do.

1. My garage is very hot and needs some type of cooling to keep my cars cool over the summer.
2. My current water heater is 14 or so years old but still works.
3. My electric bill is low in the summer as we turn off the water heater and turn up the AC.
4. The garage ceiling is insulated but the walls are cement block with no insulation.
5. The garage door is metal with no insulation.

So my current plan is to put in the new HP water heater and let it cool my garage when I am home. I will leave it running on a low setting when I leave for parts of the summer as well. I plan to put some foam insulation in the garage door.

Who has put in a HPWH? What were the costs? For the heater? Where and how did you buy it? What size did you buy? 50 gallon or 65 gallon? Why? What did you pay to get it installed? How did you get the HPWH delivered? How did you get the old WH taken away?

How well will this HPWH cool the garage when we are home and using water?

How well will this HPWH cool the garage if the HPWH is set on a low setting and the water is not used?

Who has put rigid foam insulation in their garage door? Did you hire it done? Did you do it yourself? Costs?

Other issues? Please advise. Thanks in advance for any thoughts you have.
I selected and had a 80 gallon unit installed for my parents. I did this because the older 50 gallon water heater was too small for their new needs, the utility had a rebate deal, the manufacturer was discontinuing a line and they were priced attractively, and I liked the idea of it. I'd been looking at them for awhile but it was only when it went heavily on sale plus the rebates that I bought it for them. It can also be controlled online through a phone app which is interesting when you go on vacation but aren't sure exactly what day or time you'll be back. I also installed a heat pump water heater for their pool. If you have a pool, I'd recommend that too.

If you have a high amount of consumption in your house, you might want to go with a larger one so that you can run the heater in hybrid only mode. Otherwise, just go with 50.

Look at the coefficient of performance of the hybrid hot water heaters you are considering. Higher is better.

I bought the unit through Lowe's and also had the installation arranged through them. Total cost before utility rebate was $1850. This included an additional 10% discount on the unit and parts but not on the install. The payback was 6 years before the utility rebate, 4.75 years after.

I would really recommend buying it at Lowe's (or HD maybe) and doing the install through them because that was where the problems came up. There are very few of these installed to this day and it took a lot longer than expected to install. We used Lowe's to lean on their contracted plumbers to fix some install issues which would have been more difficult otherwise. Also, it would have ended up costing more had we done the install separately but this was something Lowe's ate. Because there aren't many of them installed, they also tend to be selected more frequently for inspection by the city as my parents were. This involved another visit from the Lowe's plumbers to meet with the city inspector and resolve a couple minor things.

It does somewhat noticeably cool the garage but not to any great degree. It won't work well if you don't do something to insulate your garage. Rigid foam and/or radiant barrier.

It won't cool your garage if you're not using it since the heat pump won't be running much.

When it's installed, they'll have to drill a hole in the garage wall for a condensate drain line if there's not already a way out.

You need to clean the air filter every 3 months. if you don't, you will notice your water getting cooler since it reduces the efficiency of the unit.

Get something with a good warranty. There have been problems, particularly with the older models.

I've done rigid foam once myself to add to the R value. It's not all that hard - I used a kit. You can do that yourself. There's a good brand on amazon but I forget it now. I would definitely do this since you don't already have an insulated garage door and it's low cost. I think I spent about $100 for a double door. You could also use a radiant barrier on the door and the walls if they get direct sunlight. Get the foil through one of the places online since it's lots cheaper there than in big box stores.
brianH
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Re: Hybrid Water Heater

Post by brianH »

I like the Rheem models of HPWHs (Home Depot) better than the AO Smiths sold at Lowes.

I bought and installed my own 50g in a basement. It's more involved than a most electric/gas heaters, because the inlet/outlet pipes are not on top. Additionally, they are freaking heavy. I think my unit was North of 200 pounds. I'm a big guy, and I almost killed myself getting it down the basement stairs with an appliance hand truck.

Other than that, I love it. I leave it in heat-pump-only mode, and it's saved me a good deal of money in electric. It also helps to dehumidify the basement during the summer. Recovery in the Winter can be a bit slow, but the 50g has been sufficient for 2 adults.
Topic Author
btenny
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Re: Hybrid Water Heater

Post by btenny »

Thanks for the responses everyone. Based on the pricing I have done so far I estimate mine it going to cost about $2K. I think I will get that back in 8 years or less.

I am going to add a second valve to the heater to dump hot water to my irrigation line. That way I can set the heater to low and dump hot water out side in the summer if I am not home. That will make the HPWH run and cool the garage. And I think a little hot water in my sprinkler sprays late at night should not hurt the lawn.

My home has the water heater close to the house incoming water line. So adding this valve should be easy. There is already a dump line there for over flow.

Why would the city inspect a HPWH install? Doing this work is repairs. So no permit should be needed. Correct?

Thanks again for any comments.
THY4373
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Re: Hybrid Water Heater

Post by THY4373 »

I installed mine own. The only thing it should require above a regular electric hotwater heater is a condensate drain. This can be trivial to fairly involved depending on your particular installation.
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TomatoTomahto
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Re: Hybrid Water Heater

Post by TomatoTomahto »

I have heat pumps galore: geothermal, pool, room above the garage, hot water heater. Cooling its surroundings is a SIDE EFFECT and I wouldn’t count on it to cool your garage. Why not a cheap AC if you only need cooling and not very much cooling at that?

If you live near Boston, we can do a deal on a newly installed 80 gallon hybrid water heater I’m looking to replace with an old fashioned electric water heater. The plumber didn’t know what he was doing, and it’s wrong for our use case.
I get the FI part but not the RE part of FIRE.
Smoke
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Re: Hybrid Water Heater

Post by Smoke »

TomatoTomahto wrote: Fri Jul 05, 2019 11:11 am Cooling its surroundings is a SIDE EFFECT and I wouldn’t count on it to cool your garage. Why not a cheap AC if you only need cooling and not very much cooling at that?
Totally agree, OP will be very unhappy with the results when used in the manor described.
Seriously...just dump the hot water made to cool the garage so it keeps running?
These units are not designed for your intended application or to run continuously.
Get a unit designed for the task. A/C or swamp cooler unit.
Arguing for the sake of arguing is something I am not going to engage in.
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TomatoTomahto
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Re: Hybrid Water Heater

Post by TomatoTomahto »

Smoke wrote: Fri Jul 05, 2019 11:34 am
TomatoTomahto wrote: Fri Jul 05, 2019 11:11 am Cooling its surroundings is a SIDE EFFECT and I wouldn’t count on it to cool your garage. Why not a cheap AC if you only need cooling and not very much cooling at that?
Totally agree, OP will be very unhappy with the results when used in the manor described.
Seriously...just dump the hot water made to cool the garage so it keeps running?
These units are not designed for your intended application or to run continuously.
Get a unit designed for the task. A/C or swamp cooler unit.
This brings to mind one of my favorite throwaway lines: “that’s a funny way to make egg salad, but if it works for you ...”
I get the FI part but not the RE part of FIRE.
Topic Author
btenny
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Re: Hybrid Water Heater

Post by btenny »

I agree a regular small AC unit would cool the garage better. But to install a AC unit is big deal in my garage. I need a new power setup and holes in my wall or my roof for new AC unit. So a lot of work and a lot of money. Most likely $5K or more. Plus I still need to insulate the garage door and maybe the garage walls.

So I was looking around for alternatives. Then I noticed my regular WH is old and likely to fail soon. So I am asking what cooling I might expect from a new HPWH.
Topic Author
btenny
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Re: Hybrid Water Heater

Post by btenny »

Tomato. Why are you unhappy with your HPWH? Does it not work well or is it too slow to recover?

Please advise...
Bernie's Dad
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Re: Hybrid Water Heater

Post by Bernie's Dad »

I live in the same area as you, with a southwest facing garage that is barely attached to the house. It gets pretty hot in the garage in the summer, especially in the afternoon as the sun beats down the driveway and garage door.

Are you storing some type of historic, collectible vehicle? If not, I'd assume your car, like mine, isn't appreciably impacted by the heat you're describing. It's significantly cooler in your hot garage than it'd be if you had it parked out in a big open business parking lot for long workdays, for example. Did you know car reviewers refer to the car's interior as its greenhouse? I think about that every time I get into my car after work, where it's been parked in full sun for many hours.

IMHO, the heater replacement your considering is too expensive, won't last very long, and offers too little benefit. Do nothing. Well maybe do three things that should be fairly easy and inexpensive:

1. Stick some inexpensive foam panels into the garage door panels. I bought thick styrofoam sheets at Home Depot and cut them down to size to fit into the door panels, but it would be easier to get a kit designed for this exact purpose.

2. If it doesn't have one yet, buy and install a large pan under your water heater, with a bit of PVC piping that runs it out to your yard. This is to minimize damages once your water heater begins to leak. My first water heater didn't have this and since it's gas, local code has it up on a pedestal in the garage. When it leaked, it caused a lot of drywall damage to the pedestal. It's just superficial, but it could have been much worse as I also had woodworking equipment nearby.

3. Replace the existing water heater's anode rod every several years. If you have softened water, you should probably replace it every 1.5 - 2 years.
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TomatoTomahto
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Re: Hybrid Water Heater

Post by TomatoTomahto »

btenny wrote: Fri Jul 05, 2019 12:45 pm Tomato. Why are you unhappy with your HPWH? Does it not work well or is it too slow to recover?
Please advise...
How much time have you got? :D

We originally were going to put the HPWH in the laundry room, which is large, and gets warmed by the laundry machines. It requires a minimum of 750 cubic feet to work effectively. When we had to rejigger the design to install it in the utility room, we should probably have reconsidered and installed a regular hot water heater. Shame on me, but also shame on the plumber, because he's supposed to know.

Problems:
1. Space is too small, and there is no heat source in the utility room. We have geothermal units in there; they don't generate heat.
2. When space is small, you're supposed to vent to the outside. Since there is no longer any combustion in the room, I want to completely seal it off (i.e., replace the window with stones) except for one door.
3. The cooling of the HPWH is fighting against the copper pipes which act as a radiator (we use a circulating pump). We could insulate the pipes, and will insulate the pipes when we replace the unit. Left in hybrid mode, the cooling of the HPWH wins over the hot water in the tank, and the unit runs pretty much 24/7, literally hours after the last use of hot water. We have solar, so the cost isn't an issue, but still ...
4. I could stand the sunk cost of the HPWH if I could just set it to act as an electric water heater, but that setting resets itself every 48 hours. I could train a chimpanzee to set it to electric every other day, but think of the cost in bananas.
5. The HPWH is the loudest thing in my house now that I've gotten rid of our furnace and ACs. Geothermal, whatever you think of it, is gloriously quiet -- I have two multi-ton units in the utility room that you can barely hear, and then there's the hot water heater. Don't ask what I spent in our recent renovation to install radiant channels, Rock Wool, doubled up wall board with Green Glue in between, etc. I have no intention of soundproofing the utility room just because a HPWH is in the room.

First world problem :sharebeer
I get the FI part but not the RE part of FIRE.
THY4373
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Re: Hybrid Water Heater

Post by THY4373 »

I installed one of the original GE Geosprings back in July 2010. My ex still lives in the house and 9 years later it has been trouble free. I agree it is very noisy but in garage I don't care. As others have pointed out the cooling and dehumidification are side effects. On average my garage was cooler and less humid but if a car or two had pulled in and there was no hot water demand then it was hot. The dehumidification effect was more significant to me in VA. Recovery was not an issue but there was only three of us and our shower heads and appliances were low use. I believe mine could be reset to full resistance heat if preferred without 48 hour reset. I would happily install another one as long as it wasn't near a living area due to noise.
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btenny
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Re: Hybrid Water Heater

Post by btenny »

Tomato. Thank you. Those noise and recirculating water issues are exactly some of the things I was worried about besides the cooling effect. This home is my retirement home. It only has a attached garage and no separate utility closet. So the water heater is in the garage and about 10 feet from the master bedroom (through the garage door). So if that water heater is very noisy I do not want it. We already have noise issues with a big roof mounted AC in that area of the house.

Plus I was going to add a circulating pump as well with the new HPWH. We waste a lot of water waiting for hot water. I have not talked to a plumber on how this thing will work or get turned on or off. I was thinking a switch or a timer near the sink in the bathroom. But I am not sure what can be done. Your comment about the pipes cooling the water is a great point.

Maybe I will call one of the big AC companies and get someone out to give me some quotes and options for various stand alone AC units for the garage.

Thanks again.
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btenny
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Re: Hybrid Water Heater

Post by btenny »

Bernies Dad.

I have lived in southwest Arizona for 65 plus years. In that time I have traded several cars that were poor looking due to heat destruction and UV rays. They were also getting old and had lots of miles. So I traded before the sun rot got too bad.

But now that I am old I do not drive as much and I snow bird and leave a car in the garage all summer. So my winter car gets killed from garage heat issues. My Lincoln Zephr was 13 years old but ran good (85K miles). It was left in the hot garage for 5 summers. This caused the dash to warp and flat spot the tires. So I traded it in and rotated cars. So now I plan to leave a 6 year old Subaru Outback with 50K miles in the garage all summer. But I want to slow down the heat rot issues as much as possible. Thus the need for garage cooling.

FYI. If you look around Phoenix you will see many older cars with "scaled paint" or frosted headlamps. That is the sun and heat killing the car. This is Arizona "rust". As you expect some cars are effected by this more than others. GM cars have clear coat paint that fails from this a lot. Many Honda and Toyota cars have similar issues. Other cars like my Lincoln have plastic and leather stuff that warps and bends. The reason that there are not more of these sun baked cars is most cars get large miles on them or break down and are scraped before this gets too bad.

Good Luck.
p14175
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Re: Hybrid Water Heater

Post by p14175 »

Instead of a water heater replacement, perhaps a mini-split, through-wall air conditioner, or small swamp cooler in the garage will work.

Oops! All that was already mentioned. Do you have room for quick growing trees to shade your garage and driveway?
brianH
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Re: Hybrid Water Heater

Post by brianH »

p14175 wrote: Sun Jul 07, 2019 1:37 pm perhaps a mini-split
This would likely be the way to go. Assuming a single-story, outside wall, and available power (usually at least a 240/20 amp dedicated circuit) you can DIY a minisplit. The electrical hookup and pad for the condenser are the most involved parts.

Many videos online DIY installing the 'Mr Cool' units in garages. These can be had for around $1000-$1500, depending on BTU.
highercall
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Re: Hybrid Water Heater

Post by highercall »

brianH wrote: Thu Jul 04, 2019 7:40 pm I like the Rheem models of HPWHs (Home Depot) better than the AO Smiths sold at Lowes.

I bought and installed my own 50g in a basement. It's more involved than a most electric/gas heaters, because the inlet/outlet pipes are not on top. Additionally, they are freaking heavy. I think my unit was North of 200 pounds. I'm a big guy, and I almost killed myself getting it down the basement stairs with an appliance hand truck.

Other than that, I love it. I leave it in heat-pump-only mode, and it's saved me a good deal of money in electric. It also helps to dehumidify the basement during the summer. Recovery in the Winter can be a bit slow, but the 50g has been sufficient for 2 adults.
+1
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btenny
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Re: Hybrid Water Heater

Post by btenny »

Yes I could put in a Mini Split and forget about the HPWH. But that creates a problem in where to locate the condenser and compressor unit. My garage has a flat roof. It faces east and the south side wall faces my neighbors yard and is about 15 feet or so from his living room. That wall is where my power panel is located and the best spot for a AC unit. But I cannot put a AC outdoor fan and compressor that close to his house outside my back yard fence even though it is on my land. I could try to extend my fence to get more back yard room for the compressor but that requires neighbor and HOA approval. So a real PIA. The other choice is mounting the compressor on the roof with a hole in the roof. But then the AC unit location can be seen from the street unless I put it near the other garage wall and put up a shadow screen wall and string power across the roof. So also a PIA.

I spent a hour yesterday looking at various AC units at Home Depot. I think a old fashioned window small AC unit might work best. I can put a big hole in the wall and mount the thing near the ceiling near the door. So near the power box up out of the way an mostly away from my neighbor. Plus most of the unit is inside the garage so most of the noise is contained. TBD if a big hole in that block wall is possible without reinforcement. And TBD how noisy a Window AC unit will be in that location.

After looking at the small portable AC units I ruled those out due to cheap construction and need for constant maintenance. The things are all plastic.

Monday I am calling a local old line AC company to come out and tell me what various options costs and the schedule and non obvious issues.

Wish me luck.
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TomatoTomahto
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Re: Hybrid Water Heater

Post by TomatoTomahto »

Bytenny, not sure how thick your wall is, but some window AC are not suitable for in wall use. They overheat from lack of ventilation and don’t last long. And, of course, in wall AC are more expensive :oops:
I get the FI part but not the RE part of FIRE.
Bernie's Dad
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Re: Hybrid Water Heater

Post by Bernie's Dad »

Sounds like a good plan to check with an HVAC specialist about conditioning the garage. Keep in mind the electricity costs for running it may be quite high.

In order to make my 20' x 20' garage a little more comfortable for doing woodworking, I installed a through-the-wall AC unit, rated for 400 sq ft. I should have bought a unit rated for a larger space, because I've found that in the summer, the unit barely ever gets the room down into the 90's. It has a two digit temperature display, so it just says "HI" when it's above 99, which is most summer days. I also insulated the garage attic with R-38 fiberglass batts, the door panels with styrofoam and tinted film (for the glass), and blew in cellulose into the side and back walls.

Long story short, I think the insulation measures helped, but the HVAC definitely did not. It's expensive operate and barely does anything to cool the space. I blame the failure of the HVAC to keep up on myself, for doing it myself instead of getting a HVAC professional. In retrospect, I don't use it. I don't want to pay the significant extra electricity costs for running the system, and I'd rather spend my summers chilling out indoors instead of being in the garage. (I understand your end goal is different; just relaying my story.)
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btenny
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Re: Hybrid Water Heater

Post by btenny »

Well guys I broke down and bought the Hybrid Water heater last spring (2020). Here is how it works so far.

1. I bought the water heater from Lowes and they installed it. I also added a water circulator at the same time. Cost was about $2250 installed. This price was a good deal vs other bids.

2. It fit in the same slot as my old electric WH. But it needed more piping to hook it up. The plumber put the over flow outlet and the condenser outlet on the same drain. I also put a thermal blanket around it and insulated all the exposed pipes.

3. My wife and I love the water circulator. Now we get hot water in seconds to wash in the AM and PM.

4. The WH is only good for 1.7 showers. I have it set at 135 degrees. If we want two showers we have to wait 1-2 hours between showers for the WH to recover and give us enough hot water for a nice 2nd shower.

4. The heat pump compressor and fan makes a lot of noise. But it is in the garage so we do not hear it with the door closed.

5. We are not sure how much $$ we save each month due to the WH. Maybe $15 to $20 but maybe less. One of our heat pump AC/heaters went out the same month. So we put in a better higher seer unit. So this reduced our electric bill as well. We will get more data in the next few months.

6. The bad news. The WH cooling works so well it makes the garage ice cold. Yesterday it was 51 degrees in the garage and 64 degrees out in the air. At night it is even worse. We noticed this effect a little last spring. We left all summer and turned the WH off. Now this fall and winter I have to open the garage door so it warms up the garage. Otherwise it is freezing cold.......

7. The WH cooling effect works so well I am sure it will keep the garage much cooler if we stop snow birding and stay home and run the WH.

So there are tradeoffs......

Good Luck.
Last edited by btenny on Sat Dec 19, 2020 3:31 pm, edited 1 time in total.
mkc
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Re: Hybrid Water Heater

Post by mkc »

btenny wrote: Fri Dec 18, 2020 4:51 pm Well guys I broke down and bought the Hybrid Water heater last spring (2020). Here is how it works so far.

4. The WH is only good for 1.7 showers. I have it set at 135 degrees. If we want two showers we have to wait 1-2 hours between showers for the WH to recover and give us enough hot water for a nice 2nd shower.

4. The heat pump compressor and fan makes a lot of noise. But it is in the garage so we do not hear it with the door closed.

6. The bad news. The WH cooling works so well it makes the garage ice cold. Yesterday it was 51 degrees in the garage and 64 degrees out in the air. At night it is even worse. We noticed this effect a little last spring. We left all summer and turned the WH off. Now this fall and winter I have to open the garage door so it warms up the garage. Otherwise it is freezing cold.......
We have also had a HPWH (hybrid unit with backup electric) for the past 20 months. Cannot say what the relative energy cost is since we did this as new construction, but I wanted to add our observations regarding the 3 items above

What is the first-hour recovery and capacity of your WH (and what make/model)? Ours is a a State (same mfr as AO Smith) HPX-50-DHPT (50 gallon) with a 70 gallon FHR. We have no problem taking consecutive showers, running the washing machine, running the dishwasher, etc. Are you certain it is set in "hybrid" mode so the electric elements kick in if the rate of heating recovery falls too low?

Agree on the sound, but ours is in the crawlspace about in the middle of the house. Yes, we can hear it when it runs, but not over the refrigerator or TV if those are actively running. We do have some sound insulation directly above the unit. Our crawlspace is encapsulated and effectively "conditioned" by an HVAC register.

We have not noticed an unusual chill in the crawlspace. It seems to stay around 60-70 degrees year round (depending on season). We are in TN. The WH's heat pump operation does cool it in the summer and more beneficially reduces the humidity. We have not needed to add a dehumidifier to the crawlspace. Of course, as mentioned above, this is an encapsulated crawl space with an HVAC register so it's technically considered conditioned space, but there is no thermostat down there to control the actual temperature.
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willthrill81
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Joined: Thu Jan 26, 2017 3:17 pm
Location: USA

Re: Hybrid Water Heater

Post by willthrill81 »

In Phoenix, I would think that an evaporative cooling system would cool the garage very nicely, far more effectively than a water heater, and at far lower cost than an AC unit. IIRC, evaporative cooling systems use about one-sixth the power of AC units when the ambient humidity is low.
“It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to.” J.R.R. Tolkien,The Lord of the Rings
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btenny
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Joined: Sun Oct 07, 2007 6:47 pm

Re: Hybrid Water Heater

Post by btenny »

My HWH is a AO Smith 50 gallon unit. I could not find the model number. It is the only HWH available from Lowes. I have it set on hybrid mode which is the suggested default mode. There are three other modes, efficiency mode, electric mode and vacation mode. It says in the instructions to use electric mode (uses heater element full time) if you have high hot water needs. I raised the set temp to 135 degrees. The factory default is 125 degrees.

I also suspect I get a lot of water heat loss from the WH to my bathroom. My house is 50 years old and has copper pipes buried in the concrete slab floor. These pipes are not insulated and run 25 feet (?? not sure) from the WH to the shower and cause a lot of heat loss.
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