stat deadband vs temp differential


Old 08-09-18, 04:29 PM
Thread Starter
Join Date: Aug 2018
Location: USA
Posts: 1
stat deadband vs temp differential

Hi all. I see conflicting definitions for a thermostat "deadband" feature and some use deadband interchangeably with temp. differential.

AFAIK, if the tstat set point is 77F and I program a 3F temp diff, the compressor comes on at 80F and turns off at 77F, for the cooling cycle, right?

How would a 3F stat deadband work?

Last edited by pkdiy; 08-09-18 at 05:31 PM. Reason: clarification
Sponsored Links
Old 09-08-18, 06:25 PM
user 10's Avatar
Join Date: Mar 2004
Location: NA
Posts: 1,813
Likes Received: 6
The terms are often used interchangeably.

But a lot of stats may have the setpoint in the middle of the differential.

So with a 3F differential, set to 77F, it may turn the a/c on at 78.5F and shut it at 75.5F.

I don't recommend more than a 2F differential.

Better stats do not use a fixed differential, they have a cph setting and the stat decides how to cycle it to maintain the setpoint. Uses differential plus rate of change.
Old 09-09-18, 05:54 AM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 9,889
Deadband in my circles refers to the differential between the heating/cooling modes when a thermostat automatically switches between the two functions.
Also, the differential adjustment works differently on different controls.
They can either turn off or on when the differential is set......this could also be different between heating and cooling modes.
You need the mfrs info sheet to know how a control is set up.

An example of deadband is I am replacing two simple thermostats for heat and an exhaust fan in my small greenhouse with a digital one.
It allows me to set the differential for the on/off cycles for heating and cooling.
It also lets me set the deadband between heating and cooling.
I will set a 2 deg C deadband which will be perfect for a greenhouse.

Last edited by GregH; 09-09-18 at 06:12 AM.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes