combustion fan won't shut off - Ashby Insert - 2 years old - Triac?

[beakman]

Blew the 5amp fuse on the circuit board. Replaced. Now on shut down everything shuts down but combustion fan. Disconnected wire on POF switch. Fan keeps running. Thinking (from reading other threads) I may have a shorted triac. Am I analyzing this correctly? If so, how would I know which triac to replace? Upper, lower, or both? Thanks

 

[Lake Girl]

Welcome to the forum! Have you pulled the board to get a look at it? Take pics as you go or draw out connections so you can reinstall later. If it has been shorted, likely will find evidence on the board. Would be helpful to post pics of the board here so that some of the members who have replaced triacs can give you advice (changed title too). Good luck!

There are board repair services available
http://pelletstovecontrollerrepair.com/
http://www.api-assembled.com/support/support.htm

Board manufacturer but not sure if they do repair...
http://www.infitec.com/contact_information

 

[jzm2cc]

Usually control boards use more than one triac of the same type so you can compare one verses the other for pin to pin resistance readings. This assumes board is disconnected obviously.

Trace wire from combustion fan to board connector. Then visually trace circuit to triac or use multimeter to find it. Check for other damaged components, then order on internet.

Triacs are usually less than $5 each. Easy to replace if you have soldering experience, if not then take to electronics repair shop.