Was told when we had our AC serviced, that it's a 2 stage system, but that it wasn't set up to utilize the it & was running on single stage.

My outdoor unit is a Goodman AVXC200601AF
Blower/Furnace is a Goodman GMVC801005CNAD

Currently have a Honeywell TH6210U2001 thermostat
Coworker gave me a Ecobee Smart Thermostat Premium, but haven't installed yet

The Ecobee does say that it supports 2-stage HVAC. Is it as simple as getting that installed & set up, and it'll do its thing?
Or, does something need to be enabled on the outdoor unit and/or blower/furnace to enable the 2-stage?

quote:

Originally posted by P250UA5:
Was told when we had our AC serviced, that it's a 2 stage system, but that it wasn't set up to utilize the it & was running on single stage.

My outdoor unit is a Goodman AVXC200601AF
Blower/Furnace is a Goodman GMVC801005CNAD

Currently have a Honeywell TH6210U2001 thermostat
Coworker gave me a Ecobee Smart Thermostat Premium, but haven't installed yet

The Ecobee does say that it supports 2-stage HVAC. Is it as simple as getting that installed & set up, and it'll do its thing?
Or, does something need to be enabled on the outdoor unit and/or blower/furnace to enable the 2-stage?

Do you happen to know if they ran enough wires? If so it's really just a question of verifying wire colors end-to-end and wiring it up. You'll probably have the obvious wires that are already connected, in theory.

Edit: It's actually a ComfortBridge communicating system, but should still be compatible with the Ecobee. It would perhaps be more efficient with a Amana T6 thermostat, which may actually be a Honeywell branded unit, but not necessarily....

https://truficient.com/product...eer-multi-stage-gas/

I can look when I get home. I do know there are some unused wires behind the current t-stat.
Will need to look at the Ecobee wiring instruction/mount & confirm the colors match up to what I have.

Wouldn't it be simple for the technician who just serviced the system to set up the system for two stages?

The literature on your outdoor unit shows it is a two-stage, with two different compressor speeds and two different condenser fan speeds. You should have it set up properly, so that during lower load conditions that you are not overcooling the home.

The scroll compressor capacity is proportional to the compressor motor speed. Two stages, two speeds, means you have two capacities, thermally. On cooler days, without death valley temperatures, you can operate more efficiently at the lower speed.

Your thermostat is ALREADY good enough. T6. It is fairly smart. I have one like it. You just have to program schedules that meet your occupancy needs. It is already set up for a two-stage system, with Y and Y2 wires. Why change?

Thanks, I'll look at the t-stat wiring when I get home & see how it's wired.
I didn't recall anything related to 2-stage when I had to go into the setup menus to enable scheduling.

We had Ecobee at our old house & like them. didn't use the app much, but from time to time it was handy.
The Honeywell is a bit of a pain to program & doesn't have an Auto mode, just heat or cool. Have to manually switch between them. 1st world problems.

quote:

Originally posted by 4MUL8R:

Your thermostat is ALREADY good enough. T6. It is fairly smart. I have one like it. You just have to program schedules that meet your occupancy needs. It is already set up for a two-stage system, with Y and Y2 wires. Why change?

False, he has a 'single stage' cooling/HP thermostat...

quote:

Originally posted by P250UA5:

The Honeywell doesn't have an Auto mode, just heat or cool. Have to manually switch between them. 1st world problems.

This is also false, it wasn't programmed for 'auto mode', but it does have the option within its programming.

However, that doesn't fix the problem of it being the incorrect thermostat.

For the record I googled the thermostat number given and read the owners manual before making the post.

Pages 4 and 5 of the installation manual cover the wiring of the three different models of thermostat: TH621-2 heat/1 cool, TH622-2 heat/2 cool, TH632-3 heat/2 cool. Link

This is the wiring of the existing Honeywell

What’s the other end look like?

quote:

Originally posted by 4MUL8R:
For the record I googled the thermostat number given and read the owners manual before making the post.

Yet your conclusion is still wrong.
And you're now stating you couldn't come up with the correct answer, even with Google's help, got it.

For the record, I didn't have to Google the thermostat number in order to know 'its the wrong thermostat'.

quote:

Originally posted by trapper189:
What’s the other end look like?

Doesn't really matter given the fact its the incorrect thermostat.

quote:

Originally posted by Excam_Man:

Doesn't really matter given the fact it’s the incorrect thermostat.

It will when he gets the right thermostat. I figured I’d move the process along by asking for a pic of the other end. Also, since the units are communicating, would he need a pic of the control board as well?

I’m going to have to learn about communicating AC when I get back to Florida since the guy who installed mine no longer services communicating systems.

If the OP’s system was originally configured for operation with a single stage thermostat (which is likely) then replacing the single stage stat with a two stage model won’t offer any significant increase in performance. It would just move the staging logic from the unit to the stat. Sometimes the urge to fix something that is not broken can be strong. I would ask that if you do proceed with the stat replacement you continue to detail the process in this thread. Thanks for you time.

For those still playing along at home, here's some more photos.

Attic unit(s)



Outside condenser


Went ahead & installed the EcoBee, with the same wiring setup the Honeywell had. Still have the orange, brown & black wires not connected.



Seems the thermostat does have speed control on the fan, I can hear it working at 2 speeds & it was part of the setup when configuring the t-stat. Not sure of how to check if the compressor is operating at 2-stage or not.