New Furnace & A/C Unit

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victorb
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New Furnace & A/C Unit

Post by victorb »

I am starting to consider replacing our Natural Gas forced air unit including central air. Unit is over 25 years old and working fine(Lennox System), but I know the efficiency is nothing close to the new high efficiency systems. I have checked into local electrical & gas rebate programs. Any comments would be welcome.
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Kenkat
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Re: New Furnace & A/C Unit

Post by Kenkat »

When I did mine a couple of years ago, the payback period was in the 6-8 year range. In addition to the efficiency to be gained from a high efficiency furnace and high efficiency (15+ seer AC), there are also efficiencies due to the more modern systems using a DC powered blower fan instead of an AC powered one.

If you are confident you will be in the home over the next 10+ years, it probably makes sense to go ahead in my opinion. In fact, even if you wanted to move sooner than that, it might make sense to upgrade as any potential buyer will see the 25 year old system and assume it will need to be replaced soon anyway.
sss2009
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Re: New Furnace & A/C Unit

Post by sss2009 »

kenschmidt wrote: In fact, even if you wanted to move sooner than that, it might make sense to upgrade as any potential buyer will see the 25 year old system and assume it will need to be replaced soon anyway.
Potential buyers would not know the age of the a/c until after inspection (I doubt homebuyers go into attic to check ac when they preview homes). And after inspection, I doubt if you can do much about the old a/c specially if the inspector certifies that at the time of inspection the unit is functioning okay.
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Kenkat
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Re: New Furnace & A/C Unit

Post by Kenkat »

sss2009 wrote:
kenschmidt wrote: In fact, even if you wanted to move sooner than that, it might make sense to upgrade as any potential buyer will see the 25 year old system and assume it will need to be replaced soon anyway.
Potential buyers would not know the age of the a/c until after inspection (I doubt homebuyers go into attic to check ac when they preview homes). And after inspection, I doubt if you can do much about the old a/c specially if the inspector certifies that at the time of inspection the unit is functioning okay.
My AC is outside and the furnace is in the basement. Buyers would see mine at least.

And inspections often result in a list of defects and issues - it is very common for a buyer to come back and ask for money off or a replacement prior to finalizing the offer for items identified as an issue by the inspector. Happens all the time.
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Re: New Furnace & A/C Unit

Post by Grt2bOutdoors »

kenschmidt wrote:
sss2009 wrote:
kenschmidt wrote: In fact, even if you wanted to move sooner than that, it might make sense to upgrade as any potential buyer will see the 25 year old system and assume it will need to be replaced soon anyway.
Potential buyers would not know the age of the a/c until after inspection (I doubt homebuyers go into attic to check ac when they preview homes). And after inspection, I doubt if you can do much about the old a/c specially if the inspector certifies that at the time of inspection the unit is functioning okay.
My AC is outside and the furnace is in the basement. Buyers would see mine at least.

And inspections often result in a list of defects and issues - it is very common for a buyer to come back and ask for money off or a replacement prior to finalizing the offer for items identified as an issue by the inspector. Happens all the time.
+1 The a/c compressor is usually found outside of the home, the air handler and furnace is usually found inside of the home and depending on how many zones, you may have one in the basement and one in the attic for the second floor, like me.
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Valuethinker
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Re: New Furnace & A/C Unit

Post by Valuethinker »

I am for having very efficient kit.

Certainly on the AC side, there are big efficiency gains to be had. An old system might have been SEER 8 when it was installed and is now running at SEER 6? I think the law now says SEER 12 (or 13?) and 14-15 is a reasonable number to shoot for. When you do replace, I say go for high efficiency-- hedge against future price rises.

Similarly a modern gas furnace with condenser will run 90% efficiency a 25 year old one might be running 70-75% (I think the Energy Information Agency aka EIA has a calculator on one of its websites, savings from replacement).

BUT if ain't broke why fix it? You need to see how much money you are spending on utilities and get a good estimate of how much you will actually save.

If you are in a high cost electricity area like California or NY/ New England, then the savings could be really large (electricity can be 20 cents per kwhr, with stepped usage charges and time of day rates). Gas is also expensive in NE due to insufficient pipeline capacity.

But they might be a lot lower. You know your equipment works, natural gas prices are low. Is it worth waiting?

The downside of waiting is that you might then be in a situation where you need to make a fast choice during a heat wave or cold snap. The contractors will see you coming and you will pay a full price. If you replace now, then you can avoid that.

What I would probably do is get a rough estimate of savings, then get quotes from 2-3 reputable contractors (ask around) and see what they recommend. They are probably really busy now with the cold winter, so you probably don't actually want to do this work until the spring say June, or even the summer: schedule it in their less busy periods. You should get better service and a lower price.
scottyja
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Re: New Furnace & A/C Unit

Post by scottyja »

We had our AC and furnace replaced last fall with a high-efficiency model. Our old unit was acting up, so it needed to be replaced anyway. But this winter we've seen NO discernible difference in gas usage this year from last. Our gas company shows us a 3 year comparison, even adjusted for outside temperature, and the usage is pretty constant. I kept the same thermostat program this year, so not really sure why there's no difference. We haven't had the company come back out to inspect yet, but plan on it sometime. We generally depend on the AC more than the furnace, so we'll see if it there's any savings in electricity usage this summer. From this and other experiences, I'm definitely in the "if it ain't broke, don't fix it" camp.
onyxlinkia
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Re: New Furnace & A/C Unit

Post by onyxlinkia »

We live in CA and bought a house last yr. The ac and furnace unit are over 20 yrs old. It's working ok and our utilities expense is not too much as we watch it pretty closely.

I'm contemplating whether it's worth the trouble & money to upgrade it to a more efficient unit now or just wait till it's broken. The break even and payback will probably take more than 5 yrs.
psteinx
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Re: New Furnace & A/C Unit

Post by psteinx »

I had both furnace and A/C replaced pro-actively about 4.5 years ago, at an age of around 14 years. Both were working fine, so far as I know. There was, IIRC, a federal tax credit at the time on the order of 30%, capped at $1500, and I think some smaller credits/rebates from the local utilities or whatever. I calculated the payback period as being reasonably short, plus the benefit of getting new units with presumably a nice long lifespan.

Looking at my numbers now - I think my net, post-rebate/credits cost was around $4711, and my annual savings are now running around $450/year (gas and electricity).
Last edited by psteinx on Thu Mar 26, 2015 2:48 pm, edited 1 time in total.
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dbCooperAir
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Re: New Furnace & A/C Unit

Post by dbCooperAir »

I replaced our 27 year old furnace and A/C last year. The old one was working fine except the blower motor was loosing a bearing. I could have replace the fan motor but just bit the bullet and did a new furnace.

I got the furnace thru the supply house (from a contractor we do work for). Its a Bryant 95% 80,000 btu furnace, 2-ton 13 seer condensing unit with an encased A coil. The equipment was just under $1,900, I installed it myself. I don't recall the exact rebate but I think it was $200 from the gas company so all in it was about $1,700. Electric company did not have a rebate at the time. We don't use much A/C where we live, the payback for a higher SEER unit was way to many years out.

I did notice the newer furnace has a bit more static pressure and the plenum temp ran higher then the old unit, it was not in the sweet spot where it should be. I adjusted the gas pressure in the furnace to the bottom limit and added some more return air in the basement and that took care of it, not a huge deal. Even though the new furnace is the same BTU's as the old one I bet I could have used a 60,000btu furnace and would have worked just as well, the new ones are much more efficient.

The new furnace is about 2/3 the height of the old one, in my case it worked out great, I added this big box on the bottom with a nice filter rack (the return air stubs into the box as well) and now the all the working parts of the furnace are easy to get at, don't have to be on your knees to work on it. That was about a $125 adder from the supply house, money well spent, I appreciate anything that makes maintaining something easier.

When it comes time for a new roof the water heater will be replaced if it has not bit the dust by then. Will rid of the existing flu out the roof (one less leak) and the new water heater will be vented out the side wall like the new furnace.
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autonomy
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Re: New Furnace & A/C Unit

Post by autonomy »

I have a Lennox gas furnace approaching 20 years of age. I'm in the "don't fix it if it's not broken" camp but I am starting to worry about waking up one day and not having heat. So, if that's a huge concern to you, I'd get it replaced.
Valuethinker
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Re: New Furnace & A/C Unit

Post by Valuethinker »

scottyja wrote:We had our AC and furnace replaced last fall with a high-efficiency model. Our old unit was acting up, so it needed to be replaced anyway. But this winter we've seen NO discernible difference in gas usage this year from last. Our gas company shows us a 3 year comparison, even adjusted for outside temperature, and the usage is pretty constant. I kept the same thermostat program this year, so not really sure why there's no difference. We haven't had the company come back out to inspect yet, but plan on it sometime. We generally depend on the AC more than the furnace, so we'll see if it there's any savings in electricity usage this summer. From this and other experiences, I'm definitely in the "if it ain't broke, don't fix it" camp.
You'd really need to adjust for heating and cooling degree days to make a meaningful comparison.

I know this winter has been very cold in the eastern half of North America. Was it warmer, or colder, than last winter in your locality, by heating degree days? That's googlable (by locality).

It also depends how old the AC and furnace that you replaced last year was: the older, the greater the potential gains. For example, ACs that are 25 years ago probably had SEERs of around 8 which would fall to around 6 over long use. New ones will be at least SEER 12 (or 13?) I think. Not quite twice as efficient but significantly better.

Again with furnaces moving from mid 70s to 90% efficiency might not cut your gas bill by the full 1/6th but might cut it by 10-15%.
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Re: New Furnace & A/C Unit

Post by Valuethinker »

victorb wrote:I am starting to consider replacing our Natural Gas forced air unit including central air. Unit is over 25 years old and working fine(Lennox System), but I know the efficiency is nothing close to the new high efficiency systems. I have checked into local electrical & gas rebate programs. Any comments would be welcome.
A comment made around here is that the 2 speed or variable speed systems work a charm in terms of greater home comfort from AC (otherwise the AC cycles on and off too much, going from too cold to too hot and back). So that's definitely something to look for.
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victorb
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Re: New Furnace & A/C Unit

Post by victorb »

Thank You to all for great ideas & comments. A friend of mine put in a new Trane unit with the variable speed motor and variable heat output. He loves the more even heat and the quiet of the ECM motor.
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Re: New Furnace & A/C Unit

Post by leonard »

Couple of years ago replaced a very old furnace with a Bryant - their highest efficiency model. Very happy with it. Other than warming up the house on a winter day morning, it runs so silently you don't know it's on and keeps the house at a constant temperature without noticeably kicking on and off.
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tibbitts
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Re: New Furnace & A/C Unit

Post by tibbitts »

victorb wrote:I am starting to consider replacing our Natural Gas forced air unit including central air. Unit is over 25 years old and working fine(Lennox System), but I know the efficiency is nothing close to the new high efficiency systems. I have checked into local electrical & gas rebate programs. Any comments would be welcome.
It really depends on how long you plan to stay at your residence, what shape the rest of the house is in, and what the impact of not having heat or cooling for a while would mean to you. So far our experience has been that newer isn't more reliable, perhaps because of changes made to squeeze out more efficiency. In any case I'd suggest buying a package with a 10yr manufacturer (not dealer!) parts and labor warranty - ours has more than paid for itself. After 7 years, we would have spent two-thirds as much in repairs as we did to purchase the entire system if we didn't have that warranty, the biggest repairs coming in approximately years 3 and 6.
sk.dolcevita
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Re: New Furnace & A/C Unit

Post by sk.dolcevita »

tibbitts wrote:
victorb wrote:I am starting to consider replacing our Natural Gas forced air unit including central air. Unit is over 25 years old and working fine(Lennox System), but I know the efficiency is nothing close to the new high efficiency systems. I have checked into local electrical & gas rebate programs. Any comments would be welcome.
It really depends on how long you plan to stay at your residence, what shape the rest of the house is in, and what the impact of not having heat or cooling for a while would mean to you. So far our experience has been that newer isn't more reliable, perhaps because of changes made to squeeze out more efficiency. In any case I'd suggest buying a package with a 10yr manufacturer (not dealer!) parts and labor warranty - ours has more than paid for itself. After 7 years, we would have spent two-thirds as much in repairs as we did to purchase the entire system if we didn't have that warranty, the biggest repairs coming in approximately years 3 and 6.
In my city, if you buy through a vendor affiliated to Costco, you get 10 years warranty of parts and labor.
edawg
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Re: New Furnace & A/C Unit

Post by edawg »

We had friends who bought a highly efficient Carrier system that was "the next generation" of cooling/heat pump systems. THey gave us their 3 year old Lennox air conditioner compressor and evaporator which I summarily had installed for $600. Over the next 4 years, the "highly efficient" Carrier system died 4 times due to lightning strikes (apparently the unit was not as rugged to deal with voltage spikes). Plus there were replacements of other components due to some strange condensation issue.

Engineering is all about trade offs so don't buy the "most efficient" unless the sales person proves reliability and payback period in detail for your area in terms of KwH and / or therms of gas used. THe A/C techs I developed a relationship with over time servicing our "old reliable" hybrid system of old and new components praised Lennox and Trane and hated Carrier because the systems were so hard to work on / get parts. Of course, they also tended to sell Lennox and Trane cause that's who they had the best deal with... such is the HVAC racket. FWIW.
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Re: New Furnace & A/C Unit

Post by 4nursebee »

OP, where do you live?
How many months of cooling?
How many months of heating?
What efficiency is current unit? What would next unit be?
Why are you considering a new unit? If you metric is efficiency, why is that? Efficiency really boils down to cost to cool now versus cost to cool new.

Thoughts:
1. Heat efficiency will not improve!
2. AC trade off vs new unit would take a LONG time to payback, depending on where you live. Ceteris paribus, new units seem to have price schemes equalizing out savings on monthly bills compared to increased expense of highly efficient units. For example, a 19 seer unit might be double the price of a 13 seer (5K vs 2.5K) but would lower cooling costs to half price. In my area if my $100 per month cooling costs over 4 months was cut in half, a higher seer unit saves me just $200 a year. The payback for just the extra efficiency of the NEW unit would be 12.5 years! Now compare the fact that you already have a unit that works and the payback would be much longer than 12.5 years since you'd have to buy new.
3. An older working unit might well have better quality components less likely to leak refrigerant compared to newer units.
4. Don't compare to others with high fallutin gadgets, analyze your situation.
5. I am in the camp of not replacing until needed. If you just plain old WANT a new unit, that is fine.
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victorb
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Re: New Furnace & A/C Unit

Post by victorb »

OP, where do you live? Minneapolis, MN
How many months of cooling? 4-5 mos
How many months of heating? 5-6 mos
What efficiency is current unit? What would next unit be? In the 70s % range. SEER of A/C 6-9? 95% to 97%/highest I can get
Why are you considering a new unit? If you metric is efficiency, why is that? Efficiency really boils down to cost to cool now versus cost to cool new.
Current unit is a Lennox Natural Gas Furnace installed in 1980. Model G11E with Central Air Unit. I am just wondering how long is this going to last and I know it will fail at the worst time. If a gas valve fails, this type and style is no longer available. etc. etc. .........
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Re: New Furnace & A/C Unit

Post by Valuethinker »

victorb wrote:OP, where do you live? Minneapolis, MN
How many months of cooling? 4-5 mos
How many months of heating? 5-6 mos
OK you are in a good zone to save operating costs.
What efficiency is current unit? What would next unit be? In the 70s % range. SEER of A/C 6-9? 95% to 97%/highest I can get
Sounds realistic. You will not get the theoretical improvements in energy consumption promised, most likely, but you should get 20% reductions on both, if not 40%.

I didn't know you could get furnaces 95%? Anyways 90% is the number you should aim around above that is nice to have. On SEER I am a big fan of going to SEER15 say, vs. SEER13, on the grounds that standards will get there anyways by the time you come to sell and electricity prices are not likely to go down in the future.
Why are you considering a new unit? If you metric is efficiency, why is that? Efficiency really boils down to cost to cool now versus cost to cool new.
Also comfort with a variable speed AC unit.
Current unit is a Lennox Natural Gas Furnace installed in 1980. Model G11E with Central Air Unit. I am just wondering how long is this going to last and I know it will fail at the worst time. If a gas valve fails, this type and style is no longer available. etc. etc. .........
Either the AC or the Furnace going could be a real pain. You have there a 35 year old furnace.

I would check Consumer Reports to see if they have reliability data. Also there's an HVAC forum which has been mentioned here, and I'd look there for advice.
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jeffyscott
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Re: New Furnace & A/C Unit

Post by jeffyscott »

4nursebee wrote: 1. Heat efficiency will not improve!
Why do you say that? It would depend on what the efficiency of the new unit vs. the old is.

I have an 18 year old 80% efficiency unit, were I to replace with a 95% efficient unit we would use about 16% less natural gas for heating and save about $150 per year at current natural gas rates.

When our house was built we elected not to pay for the upgraded system that was rated 90 or 95% efficiency. Payback estimate for the upgrade was only about 6-7 years, at that time, but I thought the high efficiency would be more likely to need repair and have a shorter lifespan and that might offset the fuel savings (I also thought I'd be earning at least 5-6% on cash :shock: ). By now, I'd figure they've perfected the 90-95% efficiency models and so probably won't have reliability concerns when it comes time to replace ours.
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Re: New Furnace & A/C Unit

Post by tibbitts »

sk.dolcevita wrote:
tibbitts wrote:
victorb wrote:I am starting to consider replacing our Natural Gas forced air unit including central air. Unit is over 25 years old and working fine(Lennox System), but I know the efficiency is nothing close to the new high efficiency systems. I have checked into local electrical & gas rebate programs. Any comments would be welcome.
It really depends on how long you plan to stay at your residence, what shape the rest of the house is in, and what the impact of not having heat or cooling for a while would mean to you. So far our experience has been that newer isn't more reliable, perhaps because of changes made to squeeze out more efficiency. In any case I'd suggest buying a package with a 10yr manufacturer (not dealer!) parts and labor warranty - ours has more than paid for itself. After 7 years, we would have spent two-thirds as much in repairs as we did to purchase the entire system if we didn't have that warranty, the biggest repairs coming in approximately years 3 and 6.
In my city, if you buy through a vendor affiliated to Costco, you get 10 years warranty of parts and labor.
Interesting, although probably not to me since costco doesn't operate in the state where I live. I'd still be cautious if this is a dealer warranty and not a factory warranty. Even relatively established dealers seem to come and go frequently.
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walkabout
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Re: New Furnace & A/C Unit

Post by walkabout »

If it were me, I'd get the new system. Full disclosure, I did do that a couple of years ago. We replaced a 10 SEER 22+ year old heat pump with a 19 SEER 2 stage heat pump with variable speed air handler. Our old system was mostly working ok, but it did need a couple of service calls (not particularly expensive ones) prior to replacement. We could have gotten a cheaper system with a better payback, but we are very happy with what we got. When heating or cooling, the system typically runs a long time on low. Keeps temperature even, operation quiet, and (in summer) humidity low.

I would recommend considering a two stage A/C with VS air handler.
If you have any exposed ductwork, consider having it inspected and sealed and insulated, if necessary.
Consider a 4-5" filter rather than the standard 1" filters.

This is a very good forum for HVAC info:

http://hvac-talk.com/vbb/forumdisplay.p ... ntial-HVAC

I like this one even more:

http://ths.gardenweb.com/forums/hvac

tigerdunes at gardenweb is especially helpful in helping analyze requirements and bids. He will help ensure systems in a bid are well matched and that you are not being oversold or undersold.


Good luck!
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Watty
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Re: New Furnace & A/C Unit

Post by Watty »

Any comments would be welcome.
There is a period each spring and fall when the heating or cooling season is over but the next season has not started yet. This will vary by location but I have bought systems twice in September and gotten very good prices and service since the HVAC companies have very little work to then and they were giving good bids just to get whatever work they could. The people who did the installation could take their time to get it right since they did not have any work scheduled for later in the day.

Try to time the work to hit the slowest time of spring in your area.

In addition to saving energy you will likely find that the house is a lot more comfortable like we did with a newer system because the air handling and variable running levels are a lot better now. I forget the terminology but you the bids you get will likely have a budget, mid-range, and premium option with better levels of variable control and variable air handing. If you have the budget for it getting at least a mid-range system with a variable or multilevel fan will make a noticeable difference in the comfort of the house.

Getting the right size units is very important since getting a system that is too large will can cause a lot of other problems in addition to costing more. Bigger is not better, you want it just right. The contractors should do a "Manual J" calculation to figure out what size is needed. Search the boards for this or Google it to find out more about that. Sometimes they will just suggest using the same size unit as what is what you have now but that is not always right or things could have changed in the house since the old unit was installed.

If your hot water heater is not real new also ask if they can also replace that at the same time and how much extra that would cost. In some areas they can others they can't but in some situations where the hot water heater is right next to the furnace they can put a new one in at the same time for a very reasonable cost compared to having it replaced when it fails.
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victorb
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Re: New Furnace & A/C Unit

Post by victorb »

My sincerest thanks to all who answered and gave me excellent points to consider. It is amazing in what the vendors have done with variable speed motors, multi-stage gas valves, Hi-SEER A/C units, etc, etc....
It is really amazing what the industry is doing. BTW, planning on staying in the house for quite some time, had the entire envelope updated in 2001 with new windows, siding, roof, etc.
Valuethinker
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Re: New Furnace & A/C Unit

Post by Valuethinker »

victorb wrote:My sincerest thanks to all who answered and gave me excellent points to consider. It is amazing in what the vendors have done with variable speed motors, multi-stage gas valves, Hi-SEER A/C units, etc, etc....
It is really amazing what the industry is doing. BTW, planning on staying in the house for quite some time, had the entire envelope updated in 2001 with new windows, siding, roof, etc.
Depressingly the tech on windows and doors has advanced considerably since 2000. In the sense those products were there (German and Austrian in particular) but they are much more widely available I think.

Whether you need SEER 19 I don't know, but SEER 15 is definitely worth it. As is the 90% efficiency gas furnace. You only do these things once in your tenure in a house (normally) so 'reach' for efficiency when you do do it.
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just frank
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Re: New Furnace & A/C Unit

Post by just frank »

I think you'll like the variable speed ECM blower as an upgrade...much more comfortable and quieter/less noticeable operating.

In MN, you'll get the minimum code SEER AC unit, and that will still be aok.

One thing not mentioned is that most older heating systems were oversized, sometimes 100%, by installers that would never want to get called back by cold customers. This reduces efficiency and causes some comfort issues. If you know how much gas (therms) you used in the last winter, and how many heating degree days (hdd), you can work out how much gas was needed per hdd, therms/hdd. You can then use this number to figure out how many therms would be required on the coldest likely day (in MN, -20 to -25°F ?), and that in turn to BTU/h and an appropriate sized furnace.

On the same note, have you had an energy audit in the last 10 years? For <$500 (or free if subsidized) you can usually get a comprehensive inspection that finds the major air leaks in your house, and proposed work that can often reduce your heating bill with a decent ROI, and get a healthier and more comfortable house to boot.
Parthenon
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Re: New Furnace & A/C Unit

Post by Parthenon »

just frank wrote:One thing not mentioned is that most older heating systems were oversized, sometimes 100%, by installers that would never want to get called back by cold customers. This reduces efficiency and causes some comfort issues.
About 5 years ago I replaced a 29 year old Carrier 87% efficiency that never needed repairs with a Trane 95% efficient unit. The original was rated at 110K BTU input that I had de-rated by removing two of the burners to reduce the short cycling in the winter. The replacement furnace has an input of 80k with an output of 76k the installer had me add a switch to prevent the second stage from kicking in unless I required it. This apparently lets the furnace run around 46K, I don't recall if that is input or out, but I've never needed to let the second stage run.

As 'just frank' indicated older systems were way oversized, at least in the Chicago area, and because of a little extra insulation when I built the house I've gotten away with a much smaller furnace and the comfort and efficiency that comes with a longer running time but without the surge of heat upon start.

Ed
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jeffyscott
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Re: New Furnace & A/C Unit

Post by jeffyscott »

just frank wrote:One thing not mentioned is that most older heating systems were oversized, sometimes 100%, by installers that would never want to get called back by cold customers. This reduces efficiency and causes some comfort issues. If you know how much gas (therms) you used in the last winter, and how many heating degree days (hdd), you can work out how much gas was needed per hdd, therms/hdd. You can then use this number to figure out how many therms would be required on the coldest likely day (in MN, -20 to -25°F ?), and that in turn to BTU/h and an appropriate sized furnace.
Thanks, had not thought of this. I'll also compare to the previous winter (2013-14) that was the coldest in 30 years in the midwest. just to see if the therms per degree day was any different in a really cold winter. Probably won't make much difference but I can also subtract the summer usage to account for water heater, dryer and stove. A more significant adjustment would be for the furnace efficiency, if 300 therms is used by 80% efficient then a 90% efficient unit should need only 267.
Valuethinker
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Re: New Furnace & A/C Unit

Post by Valuethinker »

The point made previously about getting an energy audit is germane.

Before resizing for a new HVAC system, you want any insulation improvements etc. to have been implemented, because these will reduce the needs of the house.
bloom2708
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Re: New Furnace & A/C Unit

Post by bloom2708 »

victorb wrote:OP, where do you live? Minneapolis, MN
How many months of cooling? 4-5 mos
How many months of heating? 5-6 mos
[/b]
I'd say MN is closer to 7-8 months of heating unless you are super tough. :mrgreen: We are in next door North Dakota.

September can have quite a few "heat during the night/cool during the day" days. October, Nov, Dec, Jan, Feb, March are all heating. April is mostly heating with some heat + cool days. May hopefully has more cool than heat days.

Only June, July and August are "AC only" months. Not that it matters much.

We have an 18 year old Carrier system that I am contemplating replacing (Lennox). I am looking over options to be efficient but maybe not super cutting edge efficient.
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jeffyscott
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Re: New Furnace & A/C Unit

Post by jeffyscott »

For those of us that like to open windows, a/c may run very little in some years in the northern states. Many years ours has been on for only 10-20 days. Others have windows closed and air running even on days with highs in the 70s.

Normal annual is just 400-600 cooling degree days in WI, compared to 7000-8000 heating degree days.
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dbCooperAir
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Re: New Furnace & A/C Unit

Post by dbCooperAir »

jeffyscott wrote:For those of us that like to open windows, a/c may run very little in some years in the northern states. Many years ours has been on for only 10-20 days. Others have windows closed and air running even on days with highs in the 70s.
This is us to a "T", we don't really care for A/C, would much rather have the windows open, must be the long winters!
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stemikger
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Re: New Furnace & A/C Unit

Post by stemikger »

I did mine last summer. The old one was 22 years old and the AC was giving me problems. Instead of having it fixed every year, I just decided to replace both the AC and Heat. They say you should always do them together.

My house was brand new when I moved in 22 years ago and it is not a custom home, so the builder put the cheapest model in. It worked fine and I never had any issues. However, I replaced it with a Lennox (top of the line) that the company offered and it is so much cooler and very, very quiet. I didn't realize how loud the other unit was.

It was really a no brainer to go with the top of the line because I got so many rebates back and the company also gives free service for an extra year on that model which comes to a total of 3 years. The price difference between the entry level and the top was not that much.

All in it costs around $7,700.
Choose Simplicity ~ Stay the Course!! ~ Press on Regardless!!!
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HardKnocker
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Re: New Furnace & A/C Unit

Post by HardKnocker »

The new units can be tremendously more efficient than the older units. Of course it depends on what the efficiency of your current units are.

Still, it will be quite awhile before you get your "payback" on a new installation.

From a money standpoint it rarely makes sense to replace if the current unit is working properly.

It's a great idea to explore and get quotes for a new unit before you need it. Maybe you can find a really good deal from an installer. Since you are not in an emergency situation you can take your time and really research your options.
“Gold gets dug out of the ground, then we melt it down, dig another hole, bury it again and pay people to stand around guarding it. It has no utility.”--Warren Buffett
Valuethinker
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Re: New Furnace & A/C Unit

Post by Valuethinker »

dbCooperAir wrote:
jeffyscott wrote:For those of us that like to open windows, a/c may run very little in some years in the northern states. Many years ours has been on for only 10-20 days. Others have windows closed and air running even on days with highs in the 70s.
This is us to a "T", we don't really care for A/C, would much rather have the windows open, must be the long winters!
On the east side of the Great Lakes, at least (Ontario, upstate NY, Ohio) you get these heat waves that last 2-3 weeks. High 80s or low 90s and high humidity (which is worse). Particularly at night, it just never seems to cool off. And for safety reasons you can't really leave downstairs windows open at night.

So you do run the AC a lot. Especially if older residents, heart troubles etc. I would say my mother runs it 2 months pretty solid.
bloom2708
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Re: New Furnace & A/C Unit

Post by bloom2708 »

Does anyone have a gas Coleman Furnace/AC system? How does it compare to other brands discussed?

I got a price quote for a Lennox SLP98V with an XC16 AC unit. One of the Lennox dealers also sells Coleman units. I can't really find many reviews on them.

Coleman CP9C is the furnace model.
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