Comfortmaker RPJ II blowing only cold air.
 

I have a RPJ LL Enviro Plus 90. Last year the first cycle of the heat was warm, after the first cycle it was blowing only cold air. I called service and they found nothing wrong.

Just started it up for the season and it is blowing only cold air. I thought maybe I should put in a new thermostate, but don't know what to buy. Thanks,

doesnt sound like a therostat problem... have the installers back out ASAp

cascade.

You are allowed to have a link to your company website in your sig. But not in post.

Doesn't sound like a thermostat problem. more like flame sensor or a pressure switch that is not closing.