How to connect a 2 stage furnace to 1 stage thermostat?

The furnace thermostat quit working in my grandmother's vacant home and I needed an emergency solution to prevent frozen water pipes.



I bought a cheap thermostat at Wal-Mart just to get by till I have more time to do the repair correctly. After connecting it up, I found that the air flow to be very low. There was no place to connect a couple of the wires.



After getting home I did some research and found that the bad thermostat is for a 2 stage furnace, whereas the one I bought is for a single stage. And I had wired the fist stage of the furnace to the new thermostat, thus explaining the low output.



I don't know anything about dual stage furnaces. What I do know is that I don't want a low heating mode with a slow fan speed because the ducts aren't insulated and I just know most the heat will leak out before the air reaches the registers. Instead I want fast, forceful heating.



My question is this: Can I just connect the 2nd stage wire from the furnace to the thermostat in place of the 1st stage wire and be done with it? Will that cause problems for the heater to always be run in stage 2?



BTW, I've read that there is some timer setting on the furnace %26quot;module%26quot; that can be used in my situation. But I'd rather leave it set the way it is now so that I don't need to remember to change it back after I've installed the permanent 2-stage thermostat later on.How to connect a 2 stage furnace to 1 stage thermostat?
Leave it the way you have it wired. In a 2 stage, the blower runs at a lower speed until the module senses that it needs to increase the speed a little to meet the demand. It takes a lot less force to move hot air verses cold air. The hot air will not leak out of the ducts once it starts flowing it will keep moving. Sounds like you did a good job for your grandma. Hope this helps