Thermostat wiring

[canooten]

A thermostat in my office recently went on the fritz and I'm curious if there is a way to safely use a residential replacement temporarily?
We have a local company that we contract for maintenance, but with money the way it is, it seems ridiculous to pay them close to $300 to install a $50 thermostat when I can do it myself in 10 minutes. Only problem is I don't know of a source for commercial equipment that will sell to non licensed folks like myself.

I know an HVAC guy that I can probably get a good replacement from, but I need to replace it this week with *something*, even if it is temporary and I don't know if I can get a commercial thermostat from him in the short time I have.

I'm unclear on the use of two of the wires on this unit....it has the standard red/green/yellow/white (RC/RH, G, Y1, W1) but it also has a 2nd white and a blue...connected to X and Y2.

Is it possible to use an off the Lowes/Home Depot shelf thermostat for a week or so and if so, how would I wire it?

[RTF]

I don't think you need a license to purchase a t-stat. Have you looked on line for a match or equal? You can check out the following link: http://www.acsuperstore.com/store/Thermostats.html I hope it helps.

[canooten]

I know I can buy one online, just might not get it by the time I need it. I'm referring to the supply houses that sell commercial HVAC....I know of several in my area, but they only sell to dealers and techs.

I'll check this site out though....