Thermostat Cycle Rate for Steady Room Temperature

 
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Lightning
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Post by Lightning » Tue. Nov. 30, 2021 7:28 pm

I think I know the answer to this but thought I'd seek some input from you all.. When I had the handfed forced air furnace the convection blowers ran 24/7. The thermostat controlled the combustion air to the furnace to throddle the fire as needed to maintain its set temperature. This did a fantastic job of keeping the temperature of our big living room super steady..

Fast forward to the present, I have the Axeman boiler. I'm using the old forced air duct work with a water to air heat exchanger. This time, instead of the thermostat throddling the fire, it turns the blower on and off pushing air thru the heat exchanger to maintain its set temperature..

The problem is the temperature swings of the room. While the blower is off you can feel the room cool down. Then, about a full minute after my wife says she feels chilled, the thermostat calls the blower to come on, then it feels comfortable again, till the blower shuts off and the room cools again, and that's how the cycle goes.

My question is,, will baseboard radiators in this room help resolve the temperature peak and troughs better than the forced air? Or, is there a better solution to the temperature swings?
Last edited by Lightning on Tue. Nov. 30, 2021 9:41 pm, edited 1 time in total.


 
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Post by nepacoal » Tue. Nov. 30, 2021 7:50 pm

What do you have the Cycles per hour set to on the thermostat? You may just need to increase the CPH to increase the comfort level.
Last edited by nepacoal on Tue. Nov. 30, 2021 7:57 pm, edited 1 time in total.

 
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Post by Lightning » Tue. Nov. 30, 2021 7:57 pm

I've had a couple thoughts to solve this temperature swing issue. My first one was to research the thermostat to see if has an adjustable differential.. but no luck there. According to what I could find, it "learns" the heating pattern and sets up an algorithm to make the room have a "dead band" of zero degrees.. not sure if I'm understanding that correctly but it's not fixing the temperature swing issue.. my other thought was to relocate the thermostat. It's currently on an inside wall where the temperature swing is minimal. Maybe I should move it to a place in the room where the temperature swing is more substantial. This would force the blower to run more often for less time. Another thought was to use a timer to have the blower kick on for short durations between thermostat calls. Then there's the wondering about baseboard radiators.. but if I do all that work and expense to install them in this room and it doesn't work fix the swings I'm not gonna be a happy camper lol

 
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Post by Lightning » Tue. Nov. 30, 2021 7:58 pm

nepacoal wrote:
Tue. Nov. 30, 2021 7:50 pm
What do you have the Cycles per hour set to on the thermostat? You may just need to increase the CPH to increase the comfort level.
I didn't see anything about cycles per hour in the manual for the thermostat.. I will look again..

 
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Post by nepacoal » Tue. Nov. 30, 2021 8:02 pm

I've always seen 5 CPH recommended for forced air...

 
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Post by Lightning » Tue. Nov. 30, 2021 8:08 pm

nepacoal wrote:
Tue. Nov. 30, 2021 8:02 pm
I've always seen 5 CPH recommended for forced air...
Oh! So I found this in the manual..

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Post by Lightning » Tue. Nov. 30, 2021 8:12 pm

honeywell-rth8500-wi-fi-series-user-guide.pdf
.PDF | 6.4MB | honeywell-rth8500-wi-fi-series-user-guide.pdf
Here's the manual.


 
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Post by nepacoal » Tue. Nov. 30, 2021 8:13 pm

So what is yours currently set at?

 
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Post by nepacoal » Tue. Nov. 30, 2021 8:20 pm

Lightning wrote:
Tue. Nov. 30, 2021 8:12 pm
honeywell-rth8500-wi-fi-series-user-guide.pdf

Here's the manual.
My, that sure is a fancy thermostat!

 
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Post by tcalo » Tue. Nov. 30, 2021 8:20 pm

Baseboard radiators will always shed more heat than forced hot air will. When the heat stops on baseboard radiators they stay warm for quite some time. Once the fan on forced hot air stops so does the heat. There will be less time between heat calls with baseboard heat. How much less is anyone’s guess.

 
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Post by Lightning » Tue. Nov. 30, 2021 8:33 pm

nepacoal wrote:
Tue. Nov. 30, 2021 8:13 pm
So what is yours currently set at?
Its set on 5..
Which one of those would represent more cycles per hour??

 
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Post by CoalisCoolxWarm » Tue. Nov. 30, 2021 8:37 pm

What about a multi-speed fan that constantly circulates air at a lower speed, optionally kicking up to high on a call for heat?

Baseboard are more like being in a warm-enough room during the day than standing next to a fireplace. If your place has drafts, you may need to run a bit warmer setting.

 
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Post by nepacoal » Tue. Nov. 30, 2021 8:38 pm

Try the 9... See how it does. It'll just cycle more often for less time. Might end up being perfect.

 
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Post by Lightning » Tue. Nov. 30, 2021 8:40 pm

nepacoal wrote:
Tue. Nov. 30, 2021 8:38 pm
Try the 9... See how it does. It'll just cycle more often for less time. Might end up being perfect.
That's exactly what I need it to do :)

 
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Post by Lightning » Tue. Nov. 30, 2021 8:58 pm

Ok, I set that value to 9..
We'll see what happens.
I can't believe it'd be that simple ;)


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