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GoForItOrLose · Nov 3, 2008, 09:19 PM

I live in a 40 year old high-rise condo bldg. I would like to replace my 40 year old thermostats with digital models. I am not having any luck talking to people at Home Depot or Lowe's, so I thought I would try this site.

There are two wires, one white, one black, going to each thermostat. Each thermostat has a three options: heat, off, or cool.

Misc info: For approximately six months out of the year, residents have access to heat out of the convectors within our units, for the other six months, after the building switchover, air conditioning.

I am not up on the terminology, so I hope this helps. In short, I just want to know what I should be asking for when I do go to Home Depot or Lowe's, or even better, if anyone has links to recommended models, that would be awesome.

Thanks!

GoForItOrLose · Nov 4, 2008, 04:21 PM

Originally Posted by GoForItOrLose

I live in a 40 year old high-rise condo bldg. I would like to replace my 40 year old thermostats with digital models. I am not having any luck talking to people at Home Depot or Lowe's, so I thought I would try this site.

There are two wires, one white, one black, going to each thermostat. Each thermostat has a three options: heat, off, or cool.

Misc info: For approximately six months out of the year, residents have access to heat out of the convectors within our units, for the other six months, after the building switchover, air conditioning.

I am not up on the terminology, so I hope this helps. In short, I just want to know what I should be asking for when I do go to Home Depot or Lowes, or even better, if anyone has links to recommended models, that would be awesome.

Thanks!

40 views and no responses? :confused: I don't feel so bad now.

mygirlsdad77 · Nov 4, 2008, 04:35 PM

Do you have a boiler(hot water heat system), or electric baseboard heat, or forced air?

EPMiller · Nov 4, 2008, 04:58 PM

Can you tell us what brand and/or type of thermostat you have now? Mechanical (snap action, bimetalic coil) or mercury bulb? Is it one of the round Honeywell types? What letters label the terminals where the wires attach (as in W,R,Y, etc or L1, L2)? Can you measure the voltage across the two terminals when the thermostat is NOT calling for heat? Is it 24 volt or line voltage? Are the wires light gauge like normal tstat wiring or are they thicker like romex conductors?

Since you went far enough to determine the wiring colors I would assume you could give some more information. I don't quite understand how it calls for heat from convectors and cooling (usually forced air) on only two wires, but I could imagine a way it could be done, that's just not the normal way.

EPM

mygirlsdad77 · Nov 4, 2008, 05:05 PM

I'm assuming that you have a hot water heat system, and have separate ac units for each unit? Separate thermostats for heating and cooling?

GoForItOrLose · Nov 4, 2008, 05:29 PM

Originally Posted by mygirlsdad77

do you have a boiler(hot water heat system), or electric baseboard heat, or forced air?

Additional Info...

There is one thermostat per convector. Each thermostat has three settings: Heat, Off, and Cool.

The thermostat(s) are very old, so I can barely read some of the details.

This is what I do see...

When I do remove the facing, the thermostat has a "high voltage", and Honeywell T651A.

The posts on the back actually have numbers 1 - 5. One of the wires is connected to post 5, the other to post 3 (which does have L1 beside it).

Does this help?

MarkwithaK · Nov 4, 2008, 05:31 PM

Well for starters you have a line voltage stat and not the standard 24VAC variety.

hvac1000 · Nov 4, 2008, 05:46 PM

Some info on what you have

http://customer.honeywell.com/techli...0s/60-0600.pdf

http://customer.honeywell.com/techli...s/63-a2051.pdf

http://customer.honeywell.com/techli...0s/63-2051.pdf

There are replacements available but depending upon the manual or auto setup you have there might be system wiring changes that have to take place. If so the wiring changes should be done by a professional well versed in that style system control.

EPMiller · Nov 5, 2008, 10:00 AM

I could "roll my own" for this application, but there is no way I would recommend doing that to someone who doesn't know exactly what they are doing. Absolutely NO insult intended to GoForItOrLose, but anyone asking this type of question probably doesn't have enough technical background to do it. Besides, what I would do would require a box bigger than the old tstat on the wall where the old unit was.

mygirlsdad77 · Nov 5, 2008, 04:24 PM

Great advice here, time to contact a heating specialist or electrician, they will be able to supply you with the thermostat you require, as well as hook it up correctly. Good luck, Take care.