|
Sounds like you may have a gas valve problem. The operation is fairly simple as you seem to already know,
1. call for heat 24 volts from T-stat
2. inducer motor starts and is proved through a pressure switch
3. Igniter heats up
4. Gas Valve Opens and Flame is proved by flame sensor
6 Blower starts
The following general things can shut it down
Loss of pressure from inducer fan
Loss of or No Proved Flame
Flame Roll Out (flame blowing backwards essentially)
High Temperature in heat exchanger box
You can sometimes still hear the click of the gas valve when they are stuck closed by debris or other failure.
__________________
[url]www.asihvacr.com[/url]
|