Thermostats With a 0.5Degree Temp Differential

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kstills
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Post by kstills » Tue. Nov. 22, 2016 3:57 pm

I'm currently trying to find one of these, if anyone is aware of one out there I would appreciate the heads up.

 
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coaledsweat
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Post by coaledsweat » Tue. Nov. 22, 2016 4:14 pm

Robertshaw RS6110.

 
grumpy
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Post by grumpy » Tue. Nov. 22, 2016 4:31 pm

Most are one why do you want 0.5 ? Just curious..


 
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lsayre
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Post by lsayre » Tue. Nov. 22, 2016 5:46 pm

Your boilers fire cycle will be functioning like a machine gun if your T-Stat differential is only a half a degree. I believe the technical term here is 'short cycling'.

 
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Lightning
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Post by Lightning » Tue. Nov. 22, 2016 10:40 pm

No not really, I have mine set at .5 degree differential. Air is a poor conductor, our skin is much more sensitive to temperature change than the thermostat. We'll feel a couple degrees change much sooner than the thermostat so that's why it's favorable to set it at .5 differential.

It will help prevent over shoots and also call for heat before you notice the room cooling down much.

 
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lsayre
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Post by lsayre » Wed. Nov. 23, 2016 2:22 am

At least for the case of fuels such as propane, NG, and oil, short cycling has been blamed for inefficiencies. It may or may not also work that way for solid fuel heat sources.


 
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Rob R.
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Post by Rob R. » Wed. Nov. 23, 2016 6:05 am

A lot also depends on the type of heat emitter. e.g. cast iron radiation will react much differently than a hot air system.

 
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Lightning
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Post by Lightning » Wed. Nov. 23, 2016 8:20 am

lsayre wrote:At least for the case of fuels such as propane, NG, and oil, short cycling has been blamed for inefficiencies. It may or may not also work that way for solid fuel heat sources.
Yes I agree, when I researched the thermostat differential debacle it was mentioned that the 1 degree setting would be slightly more efficient but the .5 would be a little more comfortable because the temperature swing would be more narrow.

Location of the thermostat is critical also, for example it wouldn't make sense for it to be where a heat register could blow on it or directly over a baseboard radiator or attached to an outside wall or too close to a window. Seems like common sense but I didn't think about any of stuff when I installed my heating system :) had to figure it out myself lol

Back to what I said earlier about air being a poor conductor, half a degree seems ridiculous - I thought so too, but it takes time for the thermostat to feel the .5 degree change and in the meantime the temperature of the room just fell another degree or two. If it's set to notice a full degree it'll take twice as long to react.

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