[gilmore325]

I need to run about 60 feet of thermostat wire. I have hundreds of feet of coated telephone wire. Can I use this instead of buying the real stuff? I experimented with a short 2 foot section at the furnace and closed the loop and the zone triggered so I know it works but are there any concerns out there?

[Stratmando]

If you have no funds, you could temporarily try a 60' piece of your wire to test. How many conductors does your thermostat need, how many conductors and what type of phone wire?
I wouldn't do it, have seen it done.
Your thermostat is 60 Foot away? Near you return air?

[hvac1000]

With a run that long the gauge of the wire will probably not be sufficient to carry the load. Telephone wire is of a much smaller size than standard thermostat wiring I believe.

[Stratmando]

That's why I was asking, if he needed 4 conductors and had cat 5, he could double up conductors.

[hvac1000]

I see your point. I was thinking of just the old standard telephone wire not cat 5 cable. The problem sets in with any large VA draw then the relays start to chatter etc.

[Missouri Bound]

Will it work, most probably. Should you do it? Absolutely not. Thermostat wires are color coded for a reason and wiring with the wrong wire will eventually cost you a transformer or a thermostat when you "think" you have the wires in the right place. 60 feet of wire is cheaper than a new thermostat or transformer, or worst case scenario a circuit board.