[madgavdad]

Hello all,
I have a heat pump system and I am in the market for a new thermostat.
I have read many good things about the 8000.
I have not found an answer I have been looking for though.
If I buy the outdoor sensor and install it, can I set it to automatically kick on the aux heat at about 35 degrees? If I have to manually turn on the aux heat, I might consider keeping the old merc slider that I have.
Also, how does this perform with a heat pump system as far as bringing the temp up say, 10 degrees, without kicking on the aux when it's above 40 or so outside? I'm new to having a heat pump, and have heard that you should always bring the heat up gradually to keep the aux from kicking on when it's not really necessary to have the aux running.
Any help will be greatly appreciated.

 

[madgavdad]

Any heat pump thermostat will bring on backup heat if it feels the heat pump alone isn't doing what it needs to do. With the VP and outdoor sensor, you can lock out the backup above a preset outdoor temp.

No thermostat will warm the place 10° without some backup help unless locked out. Even on mild day it could take an hour or more.

Best bet if you setback is let the thermostat warm the place back up. They TRY to do it without backup but if they don't think it will happen when you want, unless locked out even the high end stats will bring on backup.

Is the vision pro capable of setting the aux heat to kick on at 35 or maybe even 30deg? I believe my heat pump is still working down to at least 35 deg.
I had read somewhere that 40 was the min that you could set for the aux to kick in on the VP8000.

5th root, what exactly will the VP not do that I need? The prestige 2.0, being over 300, don't think I can swing the more than double $$ for that.
Is it really that hard to hook up the 8000 that you need to pay a pro to do it? I am a DIY'er from way back, from laying wood floors to putting on roofs,,would have no issue going through brick to install sensor, have changed many thermostats in my time, just never one for a heat pump.
Thanks to all for the comments and the help.

 

[madgavdad]

Is the vision pro capable of setting the aux heat to kick on at 35 or maybe even 30deg? I believe my heat pump is still working down to at least 35 deg.
I had read somewhere that 40 was the min that you could set for the aux to kick in on the VP8000.

5th root, what exactly will the VP not do that I need? The prestige 2.0, being over 300, don't think I can swing the more than double $$ for that.
Is it really that hard to hook up the 8000 that you need to pay a pro to do it? I am a DIY'er from way back, from laying wood floors to putting on roofs,,would have no issue going through brick to install sensor, have changed many thermostats in my time, just never one for a heat pump.
Thanks to all for the comments and the help.

Any thoughts on the question of a professional install? Would like to do this myself. Is there anything particularly difficult about swapping the VP8000 from an old merc slider? Where does one recycle the mercury filled therm?

 

[madgavdad]

What would be a typical charge for install? If I bought it myself and just had someone out to install?

 

[madgavdad]

OK thanks, appreciate the advice.

 

[madgavdad]

I have a trane 16 seer hp with a vp 8000. This season I am leaving the setpoint the same 24 / 7 ( to see if I save money on electricity ). Before I did that when I the t stat brought the temp up by itself (adaptive inteligent recovery) I dont think it ever brought the electric heat on. If I changed the temp manually more than 2 or 3 deg it would bring it on if it was cold enough outside. The vp can lock out the elec heat above a certain temp and it can lock out the hp below a certain temp to only use elec heat. I like mine, seems to work well.

Also if you want to install a od temp sensor the manual says you need to run a seperate wire for it, you can not use extra wires in the t stat wire. That may or may not be easily done on your system.

Thanks, the extra wire thing is good to know. I am going to shop around today to get some install prices, would feel better about a professional install, even though it goes against my frugal battle to do everything myself.
I am still a bit reserved about my EM heat kicking on at 39deg, this morning it was about 30 here, and overnight the HP seemed to keep the house at 66-67 all night without the EM assist. So the wife is suggesting that maybe we get the VP8000 installed, but forego the outside sensor, and manually kick it to EM heat when we fell it's necessary. Does it seem odd to anyone that a HP would still perform @ 30deg?

 

[madgavdad]

I count on it.

The HP simply won't have (normally) the capacity to overcome a very large
setback at 30* in a short time.
..
:.02:

I meant to say WITHOUT the aux heat? @ 30deg outside temp?
If the HP will operate at that temp without aux, why would anyone want the therm to kick on EM heat at 40 deg outside temp?

 

[madgavdad]

After speaking with a local HVAC guy, I decided to go with the 8000, without the outdoor sensor. He says the outdoor sensor makes more sense if you are going to use it to kick on AUX heat, not Emergency heat. As I only have the heat pump, with electric emergency heat, he says that the EM heat will kick on when the system is taxed enough to need it, with or without the outdoor sensor. At the advice of the pros who know on this board, I have found a very resonable price and am getting the VP8000 professionally installed.
My wife is relieved that I am biting the bullet to pay for install, as she was not looking forward to having no heat source @ temps below freezing here in S In. Thanks to all for the advice, always find this site helpful.:cheers:

 

[madgavdad]

Aux heat and emergency heat is the same thing, its just how the heat is used is different. Em heat uses the elec heat as the primary source of heat and aux is supplimentary.

Probably misquoted him, I believe what he was saying was that it would be more useful to have the sensor if I had a gas backup for my heat pump system, instead of only the electric resistance coils.