Nest thermostats also have a built-in delay, like many other thermostats. This is to help save energy and also prevent system wear, especially for systems that don’t automatically delay turning on. This delay is commonly called the maintenance band, deadband, differential, or temperature swing
My question is can this delay be adjusted by the user ?
The other day following a brief power glitch during a thunderstorm, our system compressor went awry and seemed to exhibit signs of "running backward" The HVAC tech suggested the delay following outages or power glitches may not be set long enough and hence the question.
when you said "This delay is commonly called the maintenance band, deadband, differential, or temperature swing" the short answer apparently is no. And it seems crazy that google doesn't let the user change it, see e.g.
My nest (3rd gen not learning model), IMHO cycles my compressor too frequently (4X an hour?) -- but it's not an issue for damaging the compressor, just that it's going shorten my system's lifespan with all the starting.
But I'm not sure that's what you really want to know... what you really want to know is if the compressor shuts off for whatever reason, and then immediately calls for cool (or heat) say because somebody turned the setpoint down (or up, for heat)... how long will it wait; or rather will it wait long enough to protect the compressor?
somebody asked a similar question not long ago -- i wasn't really happy with the answer "I am certain that the maintenance band on your Nest Thermostat is enough to keep your HVAC system on a safe and good running condition in addition to your HVAC system's own delay system."
my system (my compressor) does not have any built-in delay, it relies on the thermostat. My old programmable (Lux from 1990s) had a 5 minute delay.
I want to know particularly in the case when there is a rapid power glitch that shuts down the compressor but the thermostat calls for cooling and then the compressor tries to restart. The other day it did this and got stuck in a reverse compressor mode which required an HVAC tech to come out and fix.
Thanks for sharing your thoughts here in the Google Nest Community.
The built-in delay on the Nest Thermostat doesn't have settings that we can manually adjust. It is depending on the HVAC capability to heat or cool and how long will it take to reach a certain temperature.
We'll take this as feedback as we are looking for more ways to improve our product and services.
I do think 2 min is too short a delay. In event of a power glitch/surge where compressor goes off... it needs to be off from 4-5 min before being allowed to restart. If too short, then you run the risk of the compressor running in reverse ... Most thermostats make this adjustable and have a 4-5 minute delay as a default. Nest should do the same.
Thanks for the reply.
We'll take this as a feedback. You could always check out this Google Nest Community Forum and our social channels to be updated on latest product and features.
The delay is 2 minutes, by the way -- at least on my Nest (3rd gen not learning). The home app just says "delayed", and the thermostat display shows a count down "cooling starting in ...."
5 minutes seems "normal" compared to other brands of thermostat but i have no idea if 2 is too few, or if 5 is over-doing it ?