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nzwasp
04-08-2019, 08:53 AM
Recently (~6 months ago) finished the basement and we have noticed that there is roughly a 4 degree temperature difference between the main floor and the basement. So 20 upstairs 16 downstairs. The living area in the basement is open planned to the stairwell. Its 650-700 square foot finished space (including the bedrooms) the contractor roughed in some electrical to attach wall heaters which we haven't done yet. We have a space heater with a built in thermostat in the living area which works alright but its still pretty cold down there. What I'm really looking for is some sort of wall mounted thermostat that works with a wall heater.

rage2
04-08-2019, 09:18 AM
Hot air rises. Cold air sinks. You need more circulation in the home. I battled with this by fucking with vents and what not for 2 years before I figured out I just need to circulate the air more. Got a new furnace and have the fan running at 10% when not calling for heat/cool to promote circulation, now my temps are within 1C of each other in every room.

ExtraSlow
04-08-2019, 09:21 AM
Yeah, run your furnace fan 100% of the time, and temperature differences will decrease. My furnace doesn't have that fancy slower speed option, so I just run the fan full blast 24/7/365.

nzwasp
04-08-2019, 09:22 AM
What thermostat allows you to run your fan at 10% power or is that a function of a new furnace?

rage2
04-08-2019, 09:29 AM
What thermostat allows you to run your fan at 10% power or is that a function of a new furnace?
New Furnace.

Ecobee allows you to turn on fan for a minimum of X mins per hour, which sort of does the same thing.

Here's my shitty excel graphs of before and after from Ecobee data:

85483

ExtraSlow's method works as well (running @ 100% 24/7), but prepare for a fun power bill.

Ecobee Fan Setting:

85484

nzwasp
04-08-2019, 09:31 AM
Does running the fan all of the time increase your power usage by much?

realazy
04-08-2019, 09:33 AM
Does running the fan all of the time increase your power usage by much?

Yes, if you have an old furnace with an AC fan.

nismodrifter
04-08-2019, 09:36 AM
Interesting. Thanks for the suggestion raj. Nest allows me to run it every hour. Will get this going and see if the situation improves.

Mitsu3000gt
04-08-2019, 09:37 AM
4 degrees sounds pretty normal. Our (finished) basement is like 10C haha - you're lucky. Older home though. Amazing in the summer, not as amazing in the winter.

ExtraSlow
04-08-2019, 09:57 AM
Does running the fan all of the time increase your power usage by much?
I'm not really sure what it costs me. We need it all spring and summer to combat incredible heat in the upstairs bedrooms. Stupid dark stucco absorbs a shocking amount of heat on any sunny day. We've been going to bed with windows open already this spring.

goldfish168
04-08-2019, 10:01 AM
What thermostat allows you to run your fan at 10% power or is that a function of a new furnace?

You could also change out your blower motor to this one that has also has an option to do a constant low speed run. It helped even out the temps in my house a bit especially with spring/fall temps right now causing low furnace/AC run times. The DC motor drops the power consumption quite a bit but will still take a while to recoup the cost depending on how much you run your fan. Available from Amazon but a little pricey right now, I've seen the price hover around $250 before:
https://www.amazon.ca/Mars-10860-Azure-Blower-Motor/dp/B00O1566GW/ref=sr_1_1?keywords=mars+azure&qid=1554738767&s=gateway&sr=8-1

Pretty simple and straight forward to install. Here's a guide:
https://thelazycouple.com/give-your-...nd-9b7bfb4f8ea

HiTempguy1
04-08-2019, 10:16 AM
Recently (~6 months ago) finished the basement and we have noticed that there is roughly a 4 degree temperature difference between the main floor and the basement. So 20 upstairs 16 downstairs. The living area in the basement is open planned to the stairwell. Its 650-700 square foot finished space (including the bedrooms) the contractor roughed in some electrical to attach wall heaters which we haven't done yet. We have a space heater with a built in thermostat in the living area which works alright but its still pretty cold down there. What I'm really looking for is some sort of wall mounted thermostat that works with a wall heater.

1) Make sure you're downstairs heat vents are wide open, and then only partially open the ones on the upper floors. As we all know, heat rises. You basically want hot air from the basement to rise up, this allows upstairs to not get boiling hot while keeping downstairs warm (you want a greater % of your hot air going to the basement)

2) Make sure you're air returns aren't blocked

3) If you have a door on the stairs, keep it closed as again, the hot air from the basement will rise and leave the space, while the hot air that has gone to the upper floors will keep the thermostat reading higher, preventing the furnace from turning on and replenishing the hot air in the basement

This will work best to minimize the differential. Putting a heater in the basement doesn't solve the problem, will waste energy, and likely will lead to the upstairs area being too hot.

Edit-
Ah shit, I left my computer an hour ago and came back and wrote this, everyone else beat me to it. Yes, run the furnace fan as well to circulate air.

nzwasp
04-08-2019, 10:31 AM
1) Make sure you're downstairs heat vents are wide open, and then only partially open the ones on the upper floors. As we all know, heat rises. You basically want hot air from the basement to rise up, this allows upstairs to not get boiling hot while keeping downstairs warm (you want a greater % of your hot air going to the basement)

2) Make sure you're air returns aren't blocked

3) If you have a door on the stairs, keep it closed as again, the hot air from the basement will rise and leave the space, while the hot air that has gone to the upper floors will keep the thermostat reading higher, preventing the furnace from turning on and replenishing the hot air in the basement

This will work best to minimize the differential. Putting a heater in the basement doesn't solve the problem, will waste energy, and likely will lead to the upstairs area being too hot.

Edit-
Ah shit, I left my computer an hour ago and came back and wrote this, everyone else beat me to it. Yes, run the furnace fan as well to circulate air.

Our upstairs runs on a different set of vents and its seperated at the furnance/ducting - we did this before finishing the basement. So we have two thermostats one for the upstairs and another (nest) for mainfloor and basement) But thanks for the tips we currently keep the basement door closed at all times. I will look at the air returns I think a couple might be partially blocked.


I'm not really sure what it costs me. We need it all spring and summer to combat incredible heat in the upstairs bedrooms. Stupid dark stucco absorbs a shocking amount of heat on any sunny day. We've been going to bed with windows open already this spring.


According to google most furnace fans are ~500W so running it full time would cost approximately $29 a month for a 4c per kwh

Xtrema
04-08-2019, 10:47 AM
According to google most furnace fans are ~500W so running it full time would cost approximately $29 a month for a 4c per kwh

Delivery/Admin/carbon tax will probably run you closer to 10c per kwh.

Did your contractor ran proper ducts and air return for the basement?

My thermostat is on the main floor so heat is always on in winter. With same ducts, I basically have to close all vents in basement because it would be cooking.

Once spring comes (now), all basement vents are opened because heat ran a lot less and it gets cold in basement. Once you are deep into summer, basement would be a great place to escape the heat if you don't have an AC. And on REALLY hot days, I try to have circulation on more often to draw cold air from basement to other parts of the house.

A space heater with thermostat would probably be the cheapest option to solve a localized issue. I assume the basement bedroom is where you are putting your MIL.

HiTempguy1
04-08-2019, 01:22 PM
Our upstairs runs on a different set of vents and its seperated at the furnance/ducting - we did this before finishing the basement.

Maybe you answered this previously, but is the damper for the upper/lower vents working? Might be worth making sure.

Darell_n
04-08-2019, 01:51 PM
Closing off the basement staircase is huge for keeping the basement warm, once the basement heat vents are open and relocated down the walls to floor level. The basement return air should also be at the floor.

rage2
04-08-2019, 01:53 PM
Delivery/Admin/carbon tax will probably run you closer to 10c per kwh.

Did your contractor ran proper ducts and air return for the basement?

My thermostat is on the main floor so heat is always on in winter. With same ducts, I basically have to close all vents in basement because it would be cooking.

Once spring comes (now), all basement vents are opened because heat ran a lot less and it gets cold in basement. Once you are deep into summer, basement would be a great place to escape the heat if you don't have an AC. And on REALLY hot days, I try to have circulation on more often to draw cold air from basement to other parts of the house.

A space heater with thermostat would probably be the cheapest option to solve a localized issue. I assume the basement bedroom is where you are putting your MIL.
I have all my vents open in the house now, and rely on the circulation to ensure even temperatures everywhere. My only struggle are the big window rooms, even with blinds, it's a few degrees higher in the day and takes a few hours after sunset to re-stabilize.

nzwasp
04-09-2019, 07:47 AM
So yesterday afternoon I bought a nest temperature sensor and put that in the basement, then I redirected the nest to use that temperature, I shut all the vents on my main floor (because of the construction last summer I found only one was open) I then made sure all the vents were open in the basement. I then set the furnace to run at a minimum temp of 19 and it ran for 20 mins and heated the basement from 17 to 19. Running the fan all day seemed to warm up the basement from 16 to 17 only. I have now set an eco mode with a minimum temp of 19 and max of 25 to minimize the amount the furnace will be on.

ExtraSlow
04-09-2019, 07:50 AM
If you want the basement and the main floor to have a lower temperature difference, you should OPEN the main floor vents, not close them.

ThePenIsMightier
04-09-2019, 07:55 AM
If you want the basement and the main floor to have a lower temperature difference, you should OPEN the main floor vents, not close them.

I think the theory is that you close ones near the thermostat so that more of the house reaches a uniform temp near the set point before the thermostat kills the heat.
Much of HVAC is very counter intuitive, though.