[beenthere]

Make sure that the transformer connections to the board aren't reversed.

You can also run a wire from the boards common to the chassi(be carefull that polarity is correct first, or you can smoke the new board).

 

[beenthere]

When you say "common" ... I take it that can mean connect ground wire from a "neutral" lead to the chassi. There is another empty lead called "park" ... Thanks. Garry

No.

Common is from the transformer secondary side.
One terminal is Marked R or +, the other is marked C or -, the C/- is common.

A neutral is never a common.


park terminal to put unused blower motor wires, so they aren't hanging in mid air, or shorting out against something else.

 

[beenthere]

Beenthere, Yuri. I switched the two secondary wires from the transformer around on the board and furnance is now working. THANKS! Garry

Congrats.

Its a fairly common thing when going from 1 style board to another.

 

[beenthere]

I didn't know that until a month ago. Was 2 steps away from calling the new board bad and getting another one and egg on my face. I don't see too much York where I am.

I'd almost swear the change the polarity of the boards every so often just to screw us up in the field. :furious:

But I can't prove it.