Will Carrier 58MVC AND 25HNA6 work with Nest?

[kingsingh]

My unit is connected to the Infinity Control thermostat that uses the ABCD wires. I did notice that both my furnace and heat pump both support 24V thermostat hook-up. Please see attached diagram. Can I just pull out my Infinity Control unit and replace it with Nest? Do I need to configure any jumpers and the 24V thermostat hookup? Also, is the 24V thermostat designed to work with non-carrier thermostats? Here is the details on Nest:

It can control:

Heating: 1, 2 and 3 stages (W1, W2, W3)
Cooling: 1 and 2 stage (Y1, Y2)
Heat pump: with auxiliary and emergency heat (O/B, AUX, E)
Humidifier or dehumidifier (HUM, DEHUM)
Fan (G)
Power (C, Rh, Rc)
Nest’s connector can accept only one of these wires:

W3, E, HUM or DEHUM

Link to the product: http://www.nest.com/

[mark beiser]

Why would you want to downgrade your Infinity system by installing a Nest thermostat?

If you are wanting control via internet, and a better looking control, look into the WiFi capable Infinity control.

[ch4man]

so you want to spend lots of money and time to have a less functional control??

what dont you like about the infinity?

the nest is a neat thermostat, but to the carrier equipment its just another dumb stat. may as well find a t-87, its also round

[kingsingh]

Why would you want to downgrade your Infinity system by installing a Nest thermostat?

If you are wanting control via internet, and a better looking control, look into the WiFi capable Infinity control.

To you it may look like a downgrade but to me I am moving into something modern. Check out the Iphone application and the features of the Nest.

[Gross]

it is a downgrade.
ive installed them...they are cool, but no where near as functional or as capable as the infinity control. get teh wifi infinity control if you want the iphone app.

[kingsingh]

You may be talking about the first generation unit. I am talking about the 2nd generation that just came out. So, I am sure you have not installed it yet. If you have installed the old one do you know the answer to my question?

[Gross]

http://lmgtfy.com/?q=nest+compatibility

[Gross]

its still a downgrade

[54regcab]

looks like you want to be a beta tester for the new nest. look into the ecobee if you dont want the infinity control. If it was me, Id go infinity wifi.

[Brent Ridley]

Carrier has a new Infinity touch control. Go to www.myinfinity.carrier.com. This stat gives you all the options that Nest has...plus more. Including the IPhone Apps and remote technology.

Upgrade to this.

[Gross]

ecobee's are really neat. expensive as all get out, but neat. still would take the infinity

[kingsingh]

I am not asking for advice on weather or not Nest is junk or not. I just want to know if it will work. Can someone please tell me if I stop using the ABCD connector, can I just wire my Nest to the 24V ports? Is this a transparent change? Will I need to adjust any jumpers?

[Brent Ridley]

The Nest thermostat will NOT work with the communicating equipment that you have. Nest is not a communicating thermostat. There will be no way to power the needed low voltage circuits.

[Gross]

since youve set up so many nest thermostats...you'd know they dont work with dual fuel set ups with out an all fuel board.....

so no, its not going to work.

[kingsingh]

The Nest thermostat will NOT work with the communicating equipment that you have. Nest is not a communicating thermostat. There will be no way to power the needed low voltage circuits.

Did you even look at the diagram I pointed out? I can either hook up a 24v thermostat or using the communicating equipment. I just want to know if the switch is transparent or not?

[Brent Ridley]

I misread. You can rewire the complete system from AHU to ODU to Thermostat and it will function. But if you have a zone system then that's a completely different story...that would take a new zone panel, etc.

You will lose any communication features you have. I.E: Fault indicator, true Dehum (not over cool), CFM and static pressure display by swapping to Nest. The Infinity controller is probably the best overall system controller out there. I just don't see why you would want to give that up.

[kingsingh]

I am changing because I don't need that complexity. I just like how simple and clean Nest look. Is the change over transparent? Do I have to set any jumpers?

[Brent Ridley]

Is this a DIY project? No DIY. Any tech should know what AHU and ODU mean. No more info from me.

[kingsingh]

Ok I just the post about DIY - Sorry I did not read this first. Anyways, thanks for your help!!

[Brent Ridley]

You can ask advice on what thermostat to use and what equipment is best in the AOP forum. This is not the place for that.

And once again, we don't offer DIY advice as a liability. Call a professional. You could harm yourself, others or your equipment.