Bill@ Honeywell

Paul Fredricks_3

Thanks Bill and Mr HD. They already have an outdoor sensor wired in down in the basement. I'll look into this more on Monday.

Paul Fredricks_5

tstat question

Bill, I have a customer with a heat pump with oil back up. Their current stat is a t874, 2 stage heat, 2 stage cool. She switches the subbase to STANDBY HEAT when it gets cool so the heat pump doesn't run.

She'd like to get a set back tstat to run this system. She told me that no one makes one. I looked at the Honeywell site and found a TH6220D1028

Will this do the job?

Home Depot Employee

Not to answer for Bill

But to share an opinion-

My visionpro with outdoor sensor programmed for heat pump operation works superb!

Bill W@Honeywell

Yes, it should work.

The TH6220 does not have a "stand by" heat function; in fact, I can't find a Q874 subbase with that function, either. Could be an OEM stat, though. Heat pump would be the first stage of heat, oil burner second. When you take the TH6220 out of the box, note the wiring terminal designations on the backplate, and be sure to follow the "heat pump" instructions. Also, follow the installer setup directions carefully, and note the specialized functions of the "L" terminal. Thanks for considering our products, if you want a complete wiring & set up sheet, go to www.customer.honeywell.com, scroll down to the lower right, type TH6220 in the box, and you will get a PDF of the tech sheet. No password is required, and it's free.

BTW Mr. Home Depot is right, if they can upgrade to the multistage VisionPro with the OA sensor, that's the best. Thanks, HD!

Home Depot Employee

Great Paul,
But I was referring a sensor that is compatable and works with visionpro stat. Then you are able to program into stat- temp lock out for 2nd stage, 2nd stage changover, read outdoor temp on stat, among other things.

Paul Fredricks_3

Yeah, I got you. The control on there now locks out the outdoor and seems to work fine. I think the customer will want to keep things as inexpensive as possible. An electronic/set back stat that I can just drop in place is going to be the way to go.