+- Woodnet Forums (https://forums.woodnet.net)
+-- Thread: Adjustable cut off thermostats (/showthread.php?tid=7346079)
Pages:
1
2
Adjustable cut off thermostats - Enigmatic - 01-30-2019
Does anyone know of a company that still makes these?
I am looking for a HVAC thermostat that allows you to set when it turns off.
Some people call them a zero degree t-stat.
It has a small switch on the back of it that says 0, +1, +2.
It lets you set the t-stat to turn off when the temp hits the actual set temp, or plus one degree, or plus 2 degrees.
So, if it's set at 70*, and you have the switch set at 0, the t-stat will shut off at 70*.
Plus one will shut it off at 71*, etc.
I used to have one, but I forgot who made it.
If this is not the proper term, what is it called anyway?
Thanks for any help.
RE: Adjustable cut off thermostats - Roly - 01-30-2019
(01-30-2019, 07:14 AM)Enigmatic Wrote: Does anyone know of a company that still makes these?
I am looking for a HVAC thermostat that allows you to set when it turns off.
Some people call them a zero degree t-stat.
It has a small switch on the back of it that says 0, +1, +2.
It lets you set the t-stat to turn off when the temp hits the actual set temp, or plus one degree, or plus 2 degrees.
So, if it's set at 70*, and you have the switch set at 0, the t-stat will shut off at 70*.
Plus one will shut it off at 71*, etc.
I used to have one, but I forgot who made it.
If this is not the proper term, what is it called anyway?
Thanks for any help.
It is called temperature differential. A lot of the digital ones have this feature but hard to just find out from the info in store ads. Hopefully on of the HVAC guys see this post. Roly
RE: Adjustable cut off thermostats - MstrCarpenter - 01-30-2019
I don't recall seeing a wall thermostat with this specific feature. What a lot of them have is a heat anticipator. It is usually used to keep a system from "short cycling". I had saved a link to remember which way to move the setting. It also explains how, and why it works. There's probably better info. available, but here it is.
https://inspectapedia.com/heat/Heat_Anticipator_Adustment.php
RE: Adjustable cut off thermostats - Roly - 01-30-2019
(01-30-2019, 11:40 AM)MstrCarpenter Wrote: I don't recall seeing a wall thermostat with this specific feature. What a lot of them have is a heat anticipator. It is usually used to keep a system from "short cycling". I had saved a link to remember which way to move the setting. It also explains how, and why it works. There's probably better info. available, but here it is.
https://inspectapedia.com/heat/Heat_Anticipator_Adustment.php
A lot of the digital ones have the feature but buried in the settings. While mine is a older Honeywell it has both an anticipator setting and a adjustable differential setting. The newer Honeywells have a cycling setting which is a little different. You have to go online and find the manual for the thermostat you are interested in to find out. Roly
RE: Adjustable cut off thermostats - daddo - 02-02-2019
Every thermostat I've installed has this neat feature- it turns the system off when the set temp is reached.
If your talking about heating and you want the stat to turn off 2* higher, why not set it at 72* instead of 70*?
Some have "occupied" mode where it changes the temperature temporarily up or down during that cycle of a program.
Perhaps your not being clear?
RE: Adjustable cut off thermostats - Roly - 02-02-2019
Think what he is looking for is how far the temperature varies from the set point before it turns on or off. Mine I can set to 1 degree or three degrees. This is a separate setting from an antipicator setting. Some new ones have a cycle rate setting, not sure how this works as compared to a differential setting. Roly
May be this explains it better.
http://www.hvachowto.com/2018/10/17/thermostats-with-adjustable-cycle-rate-differential/
RE: Adjustable cut off thermostats - crokett™ - 02-04-2019
I'm with Daddo. if you want it to turn on/off at a certain temp, set it to that temp. why set it for 70 if you want it to turn on at 72? set it for 72.
RE: Adjustable cut off thermostats - Roly - 02-04-2019
(02-04-2019, 09:43 AM)crokett™ Wrote: I'm with Daddo. if you want it to turn on/off at a certain temp, set it to that temp. why set it for 70 if you want it to turn on at 72? set it for 72.
Did you read the link. Do you think if your is set at 70 your thermostat turns heat on at exactly 70 and turns off at exactly 70 ? If they did it would start and turn off many times in a hour. They all have a differential maybe one degree or three degrees. He is looking for an adjustable one. Roly
RE: Adjustable cut off thermostats - Rob Young - 02-04-2019
Your word for today is "hysteresis".
RE: Adjustable cut off thermostats - crokett™ - 02-04-2019
(02-04-2019, 03:12 PM)Roly Wrote: Did you read the link. Do you think if your is set at 70 your thermostat turns heat on at exactly 70 and turns off at exactly 70 ? If they did it would start and turn off many times in a hour. They all have a differential maybe one degree or three degrees. He is looking for an adjustable one. Roly
No I do not think that. I know that thermostats are allowed to drift a degree or two above or below the set point. I've never found a reason to worry about setting that drift. but I guess different strokes.