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Deal Guru
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Feb 8, 2014
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sickcars wrote:
Jan 12th, 2018 8:27 am
Yes and you are correct with that thought. I know for sure our vents going to the 2nd floor are smaller more restricted square type duct work which for sure is an issue. I have actually thought about it and adding an exhaust & intake going to our 2nd floor using normal sized ducts would defiantly be a benefit however the issue is that our home is all finished & opening the walls and making a mess does not really work.
yeah, as expected :(
However I think going down to a 60,000 btu dual stage & Variable motor would help and probably solve my issues based on what a few HVAC techs have told me & 2 of those techs are good friends of mine. However a 40,000btu could also be considered & may work.
Going smaller won't work if you house needs 80K of heat. Thats why i suggest a load analysis, but dual stage and variable won't help, if your house needs more heat the furnace will try to provide it and your vent restrictions will again cause it to overheat. All that said if you only need 40K or 60K then smaller may be the answer and the vents may be enough to squeak by.
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Mar 13, 2004
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I know a few years ago when we had a tech come in for an issue he saw the duct work coming from the furnace and he even said the size was the bare min & he did not know about the runs going to the 2nd floor which was even smaller. Also our home is around 1,200sqf & 80,000btu seems like way to much for that. I think our old furnace was 80btu and it worked great because it was an older furnace without all these new sensors and so on.

If we ever have to open up walls near duct work I will for sure be trying to fix it if possible. But I may have to do a Load Analysis as you mention, do you know how thats done?
Quentin5 wrote:
Jan 12th, 2018 8:36 am
yeah, as expected :(


Going smaller won't work if you house needs 80K of heat. Thats why i suggest a load analysis, but dual stage and variable won't help, if your house needs more heat the furnace will try to provide it and your vent restrictions will again cause it to overheat. All that said if you only need 40K or 60K then smaller may be the answer and the vents may be enough to squeak by.
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sickcars wrote:
Jan 12th, 2018 8:55 am
I know a few years ago when we had a tech come in for an issue he saw the duct work coming from the furnace and he even said the size was the bare min & he did not know about the runs going to the 2nd floor which was even smaller. Also our home is around 1,200sqf & 80,000btu seems like way to much for that. I think our old furnace was 80btu and it worked great because it was an older furnace without all these new sensors and so on.

If we ever have to open up walls near duct work I will for sure be trying to fix it if possible. But I may have to do a Load Analysis as you mention, do you know how thats done?
How old is your house?
A load analysis can be done by some furnace companies. They charge you for it of course and often refund if you buy the furnace from them or you can get an energy audit done, they are available in most cities, they come and analyze the house and do a blower door test (to measure air tightness) and build a virtual house in software and print you off a report. Often these audits are done as part of government eco reno programs so they do a followup blower door test after the upgrade is done. Might be cheaper if you don't need the second visit.
The furnace requirement comes down to your location, how insulated and how airtight the house is, at 1200 sq/ft you may need 80K, you may need 40K. If you lived in a Passivhaus a 40K would be several times too large. Finally can the fan speed be turned up on your current unit?
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House was built around 1910 so its double brick and little to no insulation so on the cold days the walls are pretty cold.
We replaced the windows about 3 years ago with double & Triple pane windows & while they were installing I was getting as much spray insulation in around the windows/walls as I could. So the windows are now airtight and much better.

I don't think the fan can be changed I have had some techs ask about that and look as they were trying to lower the fan speed to see if it would help but they could find anything on the board of the furnace.
Quentin5 wrote:
Jan 12th, 2018 9:05 am
How old is your house?
A load analysis can be done by some furnace companies. They charge you for it of course and often refund if you buy the furnace from them or you can get an energy audit done, they are available in most cities, they come and analyze the house and do a blower door test (to measure air tightness) and build a virtual house in software and print you off a report. Often these audits are done as part of government eco reno programs so they do a followup blower door test after the upgrade is done. Might be cheaper if you don't need the second visit.
The furnace requirement comes down to your location, how insulated and how airtight the house is, at 1200 sq/ft you may need 80K, you may need 40K. If you lived in a Passivhaus a 40K would be several times too large. Finally can the fan speed be turned up on your current unit?
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sickcars wrote:
Jan 12th, 2018 9:19 am
House was built around 1910 so its double brick and little to no insulation so on the cold days the walls are pretty cold.
We replaced the windows about 3 years ago with double & Triple pane windows & while they were installing I was getting as much spray insulation in around the windows/walls as I could. So the windows are now airtight and much better.

I don't think the fan can be changed I have had some techs ask about that and look as they were trying to lower the fan speed to see if it would help but they could find anything on the board of the furnace.
So you probably need the 80K, brick is a poor insulator in fact it can be considered a conductor of heat. The windows will only help a bit unfortunately.
This also means you probably have lath and plaster, a big job to open up compared to drywall
That said you want to raise the blower motor speed, not lower it, lowering it means less heat removal from the exchanger meaning quicker overheating.
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I think we did at one point but my parents have renovated the house so pretty much all of the walls now are regular drywall. Just at the time when everything was open no insulation was installed (no idea why it was before my time)

Maybe they were trying to raise the speed of the fan I'm probably wrong.

Yes the windows did help a bit, as our old ones were very drafty but nothing compared to having proper insulation. This is why if we end up renovating our bathroom I plan to insulate it like crazy and if possible push insulation to another rooms since the bathroom will be fully opened to help a little.
Quentin5 wrote:
Jan 12th, 2018 9:27 am
So you probably need the 80K, brick is a poor insulator in fact it can be considered a conductor of heat. The windows will only help a bit unfortunately.
This also means you probably have lath and plaster, a big job to open up compared to drywall
That said you want to raise the blower motor speed, not lower it, lowering it means less heat removal from the exchanger meaning quicker overheating.
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sickcars wrote:
Jan 12th, 2018 9:35 am
I think we did at one point but my parents have renovated the house so pretty much all of the walls now are regular drywall. Just at the time when everything was open no insulation was installed (no idea why it was before my time)

Maybe they were trying to raise the speed of the fan I'm probably wrong.

Yes the windows did help a bit, as our old ones were very drafty but nothing compared to having proper insulation. This is why if we end up renovating our bathroom I plan to insulate it like crazy and if possible push insulation to another rooms since the bathroom will be fully opened to help a little.
Drywall is good, you can open it up without too much cost to enlarge vents and repair it. However insulating brick buildings can be problematic, its a water reservoir cladding, meaning it holds water and freeze/thaw cycles can shatter it over time. There is some research on this and not all brick is susceptible, you can get yours tested to see if it will hold up to insulation. The heat escaping from being non insulated keeps water from freezing in it and helps drive water out. But if you have bad brick the only safe way to insulate it is on the outside then install new cladding.

http://www.greenbuildingadvisor.com/blo ... -buildings
https://www.treehugger.com/green-archit ... years.html
https://buildingscience.com/documents/i ... k-as-brick
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Jan 11, 2018
2 posts
Hello,

I'm sorry to interrupt but I'm wondering if anyone can help me with an opinion, it's kind of an emergency.

Recently my HVAC has been making low motor noises and it's been generating more heat than the thermostat tells it to. My superintendent diagnosed it as a broken actuator (it's a fan coil setup with a 3-way valve, see attached picture). However, I think it could be that the spring/piston cartridge is stuck in the three way valve. In this video (
the cartridge is able to move but I can't move mine at all.

If I were to replace the cartridge, would I just shut off the water from my main and remove the 3-way valve? There doesn't seem to be any shut-off valves near the HVAC - does my main supply water to the HVAC coil or does it come from a different source?

Thanks very much
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Dec 17, 2007
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sickcars wrote:
Jan 12th, 2018 8:55 am
I know a few years ago when we had a tech come in for an issue he saw the duct work coming from the furnace and he even said the size was the bare min & he did not know about the runs going to the 2nd floor which was even smaller. Also our home is around 1,200sqf & 80,000btu seems like way to much for that. I think our old furnace was 80btu and it worked great because it was an older furnace without all these new sensors and so on.

If we ever have to open up walls near duct work I will for sure be trying to fix it if possible. But I may have to do a Load Analysis as you mention, do you know how thats done?
Your old furnace might have been 80k btu, but only 65% efficient. Which means its actual output was only 52k btu. A new high efficiency 80k furnace would have an output of about 76k btu, which is way oversized. A 60k btu furnace is what you would be after. It's output is about 57k btu which is much closer to your old furnace
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Very possible, probably why most of the techs I have talked to has suggested 60k but also dual stage.

schade wrote:
Jan 12th, 2018 8:49 pm
Your old furnace might have been 80k btu, but only 65% efficient. Which means its actual output was only 52k btu. A new high efficiency 80k furnace would have an output of about 76k btu, which is way oversized. A 60k btu furnace is what you would be after. It's output is about 57k btu which is much closer to your old furnace
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Mar 25, 2003
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question
the original Furnace Inducer Blower Motor in my furnace is 115 Volts 1.8 Amps 3400 RPM
is it ok to replace with a 115 Volts 2.35 Amps 3400 RPM ?

is a Lennox Furnace
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sickcars wrote:
Jan 12th, 2018 9:17 pm
Very possible, probably why most of the techs I have talked to has suggested 60k but also dual stage.
What efficiency is your current furnace?
Is it chimney vent, black/white pipe? Also how old is it?
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Jun 2, 2008
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Toronto
Hey Guys, got a question which maybe you'll be able to answer...

Recently in my house (as the weather has been getting colder), I noticed the humidity in the house was rather low as read by my Nest thermostat. So, I decided to turn my Wait 1000 Drum Whole Home Humidifier on. This humidifier is not connected to the Nest. It is attached to the cold air return on my furnace. I operate it Manually, by adjusting the dial when needed. The Nest is also on a wall about 15 Feet away from 1 of the floor air duct returns (Which is the closest to the Humidifier, about 5 feet of ductwork from that return vent to reach the mounted humidifier and control).

I have set it to 25% as outside temp has been roughly between -10 to -20 'C. My Nest Thermostat is set to heat the home to 24' C.

Now, after a couple days being at the above settings, I checked the humidity at the Nest Thermostat, and on a separate pocket hygrometer that I placed upstairs in bedroom. The Nest is reporting Humidity level at 31%, and the upstairs reporting Humidity at ~55%.
These readings seem like a huge difference from what is set on the Humidistat. Is this normal? Is it just a matter of me finding that common level where I will just have to slowly lower/adjust the Humidifier until the Nest and other pocket hygrometer fall within reason, ignoring the numbers on the Humidifier dial?


Thanks all.
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May 13, 2016
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What is the best bang for your buck gas furnace covered under the Ontario rebate program? Same goes for AC. Thanks
So easy, even I can do it.
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I think its a 90-92% efficient not sure exactly. Right now its probably around 7 years old give or take. York furnace.

Its the updated pipe to the outside for both exhaust and intake

Quentin5 wrote:
Jan 13th, 2018 4:23 am
What efficiency is your current furnace?
Is it chimney vent, black/white pipe? Also how old is it?
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