Good afternoon. I have two ADC T3000’s (one for the downstairs, the other for the upstairs). I wanted to test to make sure sure our emergency/Aux heat was functioning correctly while I had the chance with it being colder (We live in Savannah, GA) and our system is only 18 months old American Standard 2.5 Ton . With both thermostats switched over to emergency heat, the downstairs will call for heat emergency heat, but the upstairs thermostat will not (both work fine calling for normal heat using the condenser).
I had our HVAC Tech come out today and he confirmed with his multimeter it will connect voltage for the fan, but not for emergency heat indicating a failure to connect voltage from the upstairs thermostat (pointing to an issue with the upstairs T3000).
I’m not sure if this is related or not, but I do see from time to time only that upstairs thermostat will go into protect for no reason. Meaning when I just want to go to the menu and not switch the temp, it will give me that message nor anytime around when a lockout period would be in place. I also hear a very slight electronic buzzing/hum whereas the downstairs doesnt (this has been like this since day one). After doing some research, could both problems be related where it might just need an isolation relay?
TYIA
After doing some research, could both problems be related where it might just need an isolation relay?
Yes, an isolation relay is a common requirement on T3000 thermostats. They use digital relays which are very sensitive to variations in power. If you see that message frequently an Isolation relay will likely solve it by having power for that component switched through the relay, not the thermostat.
I have never seen a message on either thermostat for a relay, only hypothesized as I occasionally see it give me a protect message but only on the upstairs thermostat. The other odd thing I noticed that same thermostat (upstairs) never senses my movement (meaning will light up) like the one downstairs does when I’m directly infront of it or walk by (yes I have it set to on for both thermostats)
I occasionally see it give me a protect message but only on the upstairs thermostat.
That’s the message I am referencing. If you see “System Protect” on that Upstairs thermostat it could benefit from an isolation relay.
Thank you, I will give that a shot and see if it clears the occasional protect message. However, if that doesn’t also fix the issue with the thermostat not calling for emergency heat (confirmed by the company that installed our new HVAC system), would that indicate a faulty thermostat and would that qualify for warranty since I purchased it directly from Surety?
We honor the manufacturers warranty which is 1-year from the purchase date on items purchased through Surety.
Thank you tyler, I couldn’t find the warranty information but I appreciate you following up and confirming