I have a Lennox G20 which I think has a bad BCC. It is having trouble starting up. It sounds like some of the relays on the board are bad. It is making an odd clicking noise on the board. It is Sometimes it does not ignite the burners and sometimes it does. When the burners do ignite, the fan sometimes does not come on and so the burners shut off. Can you help me verify that it is the BCC and not the igniter or the transformer?

Quote;;verify that it is the BCC and not the igniter or the transformer?

When a igniter is bad,it doesn`t work even once in a while

When transformer is bad, nothing will work at all,the transformer is what sends low voltage power to the controls

OK, then. I guess it's off to the store to buy a new BCC. Thanks.

Ok, so here is a follow-up. I bought the part from http://www.hvacpartsshop.com/and reaved it the next day. I just installed it and the furnace appears to he working normally again. Thanks for the help.