On 2012-01-01, Tony Hwang wrote:


Nate Nagel wrote:
On 12/31/2011 10:10 PM, Ignoramus21023 wrote:
I have a commercial building with about five thermostats for
heating. They are of the non-smart variety, maintaining the same
temperature regardless of time of day, with only a pair of 24v
contacts leading to them.

Given that it is a 10,000 square foot building, this is costing me a
lot of money spent on unnecessary heating during nighttime.

During the day, I want the temp to be 47 degrees, and at night, I
would be happy with 38 degrees or so.

Do programmable thermostats need a separate power supply, or can they
run themselves from just a pair of 24v wires that they open and close?

In other words, if I buy and install programmable thermostats, will I
have to run any additional wiring?

Thanks
i

I think if your thermostat uses power it'll require at least three
conductors. Unless you can find a battery-powered thermostat?

nate

Hi,
Yes, if three leads coming into present 'stat for blower, heat, 24V AC
control power lead, you can have programmable 'stat easily. Just make
sure the 'stat you will get has enough wide range of temp. settings.

I have only two leads.

i