My very expensive American Standard Gold S9X2 high-efficiency gas furnace works great in 30 degree weather and up, but won’t keep my house warm when it gets in the 20s and single digits outdoors. In fact, when it recently dropped to zero, we woke up to 58degrees in here. I own a 95 yo house with 1,400 square feet (1,700 Square feet of heated space including the lower level rec room.). It took 5 hours to get up to 73 degrees inside. It’s a 60K BTU furnace. I have 40 windows in my home with new storm windows. Everything I’ve seen online says to multiply heated square footage by 50 in zone 4/5 (northern suburbs of Chicago) which means they should have installed a 70 or 80K BTU furnace. The HVAC company that sold and installed my furnace refuses to do anything except they did change the thermostat which didn’t help. I fear what will happen when we experience a normal winter (it’s been unusually mild this winter here in the upper Midwest.). Any suggestions would be much appreciated! Thank you!
New furnace undersized!
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Do you know what size the furnace that was replaced was? I'm guessing this 1 is considerably smaller and I would certainly think the company gets over to you should be responsible to make sure it heats your home sufficiently. As the PP said, it's time to consult a lawyer or depending on the laws up your way maybe you could go to Small Claims Court. Another option would be talk to 1 of your local television stations, oftentimes they will do a story on it something like this and companies hate that.
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Forget everything you read online because it's nonsense.
The only way to confirm it's undersized is to do a load calculation.
It's highly unlikely that your furnace is actually undersized.
It's very likely that there's a problem preventing the furnace from supplying the amount of heat it should.
Here are some possibilities:
1. The second stage is not working and it's running at 40k btu. Even on first stage it should be able to keep up at 30F.
If you have a single stage thermostat, the second stage should be coming on after a running on first for a certain amount of time, usually 10 minutes.
If you have a two stage thermostat, the second stage should come on when the indoor temp is below the setting and/or it detects first isn't keeping up any more.
2. A safety is causing the burners to cycle off during a continuous call for heat -> overheating causing the high limit to cycle, venting or condensate drain lines not done right causing pressure switch to open
3. Furnace is under-fired.
The gas pressure on both stages, temperature difference between supply and return, btu input (clock meter), and if necessary draft be checked.
You need to contact the contractor again and give them a chance to rectify the problem. Ask if it was properly commissioned.
Don't leave bad reviews yet yet, definitely don't try to sue them.
If you were angry at them when you called and just said it's undersized - that could explain the failure to do anything.
Honest mistakes can happen.
If they continue to refuse, get another american standard dealer to check the installation and setup.
Did the company fill out and provide you a copy of the commissioning report?
The sizing method you posted is incorrect. Sizing isn’t done via square footage. It’s done via an AHRI approved load calculation.
You can see what’s involved with this free version-
www.loadcalc.net
The sizing method you posted is incorrect. Sizing isn’t done via square footage. It’s done via an AHRI approved load calculation.
You can see what’s involved with this free version-
www.loadcalc.net
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Our western NY 120 year old 1700 square foot farmhouse uses a 60K BTU furnace. At 10 below zero it cycles and heats without breathing hard. We have about double the insulation of a new house, though.
Hi Steadaroo.
While you are resolving this pick up one of the wood cabinet electric space heaters. Cost a little in electricity but only needed on those really cold nights, beats waking up to 58°.
I work the other side of the tracks and love undersized furnaces, smaller will cost less to run. But it needs to be matched to the house and the load calculations will help point to where you are losing the heat. There are heat loss calculations that can be applied to specific areas of the house. One that is often an issue is air sealing and should be done before all others.
Users list is good so see if it can help. if not, improving the energy efficiency of the house is a double win.
Bud
While you are resolving this pick up one of the wood cabinet electric space heaters. Cost a little in electricity but only needed on those really cold nights, beats waking up to 58°.
I work the other side of the tracks and love undersized furnaces, smaller will cost less to run. But it needs to be matched to the house and the load calculations will help point to where you are losing the heat. There are heat loss calculations that can be applied to specific areas of the house. One that is often an issue is air sealing and should be done before all others.
Users list is good so see if it can help. if not, improving the energy efficiency of the house is a double win.
Bud
It should cycle less and less until it reaches its design temp, where it should run constantly.
It’s much harder and less efficient on the equipment cycling on and off then running.
In reality you want it to “breath hard”.
Ditto for my 22 year old house in Southern Ontario, with 60K furnace 1450 sq foot on main floor, plus 1450 sq ft basement. Its likely better insulated than most, however.
40 windows ????? I wouldn't even be able to start to figure out where to put all of them.
I read somewhere that 85% of all heat loss is through the windows. And 40 windows in a 1700 sq ft home is a huge amount. Meaning a huge amount of heat loss, even with storm windows. In comparison my 1500 sq ft bungalow has 17. Possibly someone sitting in a office and never actually seeing the house did the heat loss calculation.
Heat loss calcs are required in this area now to prevent installers from over sizing the equipment.
Heat loss calcs are required in this area now to prevent installers from over sizing the equipment.
A few pictures of the house would help.
40 is a lot of windows and the house is actually 1,400 ft², but I did a house a bit north of me and it had glassed in porches all the way around, plus windows on the main shell of the home, a lot og glass but in that case all for the good.
Although storms help they may not improve all of the air leakage. Can you tell us if other energy improvements have been made? Do walls and ceiling have insulation?
We can do a basic energy calculation for you with more information.
@Yodaman "I read somewhere that 85% of all heat loss is through the windows."
I think 85% heat loss for just the windows is way high even for 40 of them.
Bud
And BTW, welcome to the forum
40 is a lot of windows and the house is actually 1,400 ft², but I did a house a bit north of me and it had glassed in porches all the way around, plus windows on the main shell of the home, a lot og glass but in that case all for the good.
Although storms help they may not improve all of the air leakage. Can you tell us if other energy improvements have been made? Do walls and ceiling have insulation?
We can do a basic energy calculation for you with more information.
@Yodaman "I read somewhere that 85% of all heat loss is through the windows."
I think 85% heat loss for just the windows is way high even for 40 of them.
Bud
And BTW, welcome to the forum
If you used a credit card then contact the bank and ask them to reverse the charge. I would also contact the better business bureau and file a complaint with them and do a negative posting on Yelp. I would also submit a complaint to the state contractor license board for this business.
What I do not understand is how you stood by and let them install a 60K BTU heater in your house. As soon as I saw the furnace at my house was not what was in their quote I would have sent the contractor on his way. Always always always get a quote that specifies exactly what is being done and which parts and materials will be used for the job.
I would tell the contractor (followed up with a letter and a fax) that you that you will give them 10 days to replace the furnace or you will have another contractor do it and then take them to court.
A lot of the responsibility lies with your not properly managing the job. Hopefully it will be a learning lesson.
What I do not understand is how you stood by and let them install a 60K BTU heater in your house. As soon as I saw the furnace at my house was not what was in their quote I would have sent the contractor on his way. Always always always get a quote that specifies exactly what is being done and which parts and materials will be used for the job.
I would tell the contractor (followed up with a letter and a fax) that you that you will give them 10 days to replace the furnace or you will have another contractor do it and then take them to court.
A lot of the responsibility lies with your not properly managing the job. Hopefully it will be a learning lesson.
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Who said a 60k was not what was quoted?
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I don’t want mine to run continuously at extreme temps. I realize that is the most efficient but I think it is better to have a long run cycle, a rest period, and another long run period. Of course, short cycling is not good. Bearings and bushings tend to run hot when run continuously.
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It's not.
What wears out a furnace and reduces comfort is cycling.
Heat exchangers, relays, gas valves, hot surface ignitors would pretty much never die if there was a furnace that never cycled.
Only motor bearings wear out faster if the motor runs continuously.
Forced air has a lousy reputation because most systems provide short, noisy, drafty blasts of hot air. It's much nicer to have a continuous flow of heat especially in extremes.
Single stage units are already too big except for a few hours each year when perfectly sized and it makes no sense to compound that problem.
The nicer 2-stage and modulators shouldn't be oversized either because doing so can defeats the purpose of spending more money.
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Short cycling is bad. Normal cycling is not. If cold weather makes it run all the time, in colder weather it will not keep up. It can always get colder or windier, and if you don’t have a little extra capacity you will have a cold night. A huge furnace that short cycles with brief blasts of hot air is bad. A furnace that runs 90% of the time in cold weather is good, it has a little left over for more cold or excessive wind.
We had a cold wave a few years ago and the power went off for a few hours. Neighbors who had “just right” sized furnaces that ran continuously in that cold weather saw their houses being cold for days because their equipment could not catch up. Mine had just a bit more oomph that let it catch up more quickly.
We had a cold wave a few years ago and the power went off for a few hours. Neighbors who had “just right” sized furnaces that ran continuously in that cold weather saw their houses being cold for days because their equipment could not catch up. Mine had just a bit more oomph that let it catch up more quickly.
“bit more oomph“ means your furnace is sized right for about 0.05% of the operating conditions it’ll see any given season.
Equipment, if anything, should be sized a hair on the small side. Let it run, it’ll be much happier and you’ll be much more comfortable. You can always supplement if needed for the very small amount of time the equipment can’t keep up.
Equipment usually doesn’t put out its rated capacity anyhow because of so many people believing bigger is better and installing an oversized unit on undersized duct.
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A properly sized unit will have enough capacity to maintain in the most extreme conditions encountered in an area, running continuously.
The most extreme conditions occur only a few hours each season and so a safety factor should not be added.
In reality they come in 20k btu increments so there's almost always a small safety factor and it doesn't make sense to add to that. Most houses with a 50k heat loss, done right will end up with a 60k input/57k output for example.
You don't size for power outages so that it's possible to raise the temp quickly from 45 to 70 in extreme cold because doing so reduces comfort the rest of the time.
In areas with frequent outages, wise to have second source of heat that runs without electricity or a generator.
I'm betting your neighbours units were not actually too small, more likely they were not properly tuned and were outputting fewer BTUs than rated due to being underfired, having insufficient airflow or cycling on high temp limit.
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