Replacing Motherboard
#1
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Replacing Motherboard
Brother came out and diagnosed my system and said the motherboard was bad. He's an AC guy so I trust it to be the case. Of course he's out of town now that I got the replacement board. I'm pretty savvy and can usually figure things out, but this one has me stumped. New board is nothing like the old one. A few labels are the same, but for the most part it's different.
The next line in the included instructions says reconnect the edgecard connector and as you can see there is no place for it. The old board had this connection right of center on the top edge.
Secondly, there's lots of plugs that do not have the same labels, so deciphering this will be fun as well. Any advice shy of calling a pro is welcomed.
The next line in the included instructions says reconnect the edgecard connector and as you can see there is no place for it. The old board had this connection right of center on the top edge.
Secondly, there's lots of plugs that do not have the same labels, so deciphering this will be fun as well. Any advice shy of calling a pro is welcomed.
#2
Welcome to the forums.
I'm assuming the board on the left is the new one ?
The one on the left uses a 12 pin nylon connector while the board on the right uses the edge connector. They really aren't interchangeable unless you have the 12 pin plug.
Post the two board model numbers. Maybe there is a replacement plug available.
I'm assuming the board on the left is the new one ?
The one on the left uses a 12 pin nylon connector while the board on the right uses the edge connector. They really aren't interchangeable unless you have the 12 pin plug.
Post the two board model numbers. Maybe there is a replacement plug available.
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I just called the person I bought the new board from and we determined I was sent the incorrect replacement. Already boxed it back up. Thank you for replying though PJmax. You're right also, what I received had a nine pin plug and the board had a 12 pin receptacle so this was wrong too.
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Got the new board, installed, no error light code, but no ignition. Lit it with a match and everything seems to be working properly except for ignition. Could it just be a bad igniter now?
#5
You replaced your board with the one with the edge connector.... correct ?
There's been a lot of problem with that edge connection system. Either the board corrodes or the pins in the connector do.
You need to check for 120v at the igniter terminals. If you don't know which ones those are.... post the board model number and I can point them out.
Is this the same problem your old board had ?
There's been a lot of problem with that edge connection system. Either the board corrodes or the pins in the connector do.
You need to check for 120v at the igniter terminals. If you don't know which ones those are.... post the board model number and I can point them out.
Is this the same problem your old board had ?
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I was getting an error flash code for sticking gas valve before. I think that not the case any longer because I can hear the gas start and I can light it with a match.
Yes, got one with the edge connector now.
I'll try to check for 120v tomorrow.
Now board looks exactly like the old board in the pic I posted before. It's the one on the right.
Thanks you for your help by the way!
Yes, got one with the edge connector now.
I'll try to check for 120v tomorrow.
Now board looks exactly like the old board in the pic I posted before. It's the one on the right.
Thanks you for your help by the way!
Last edited by Divebomb; 12-30-15 at 08:09 PM. Reason: Added pic
#7
No problem. Still post the board number for me. I see so many I can't keep them straight.
Not actually a gas valve code.... more like.... no flame when there should be. Most boards have no idea if the igniter is working so the board expects your burner to light. When it doesn't.... a gas valve issue is mentioned.
Not actually a gas valve code.... more like.... no flame when there should be. Most boards have no idea if the igniter is working so the board expects your burner to light. When it doesn't.... a gas valve issue is mentioned.
#9
The ignitor terminal is labeled HSI. the other side lands on neutral.
Looks like the replacement accepts an edge pin connector or a 9 pin plug.
Looks like the replacement accepts an edge pin connector or a 9 pin plug.

#10
That is a true replacement board with both connectors...... pretty cool.
When you have some spare time.... look at the back of your old board. A common problem is the solder on those two resistors goes bad from the heat they generate. Those resistors supply power to the relays.
When you have some spare time.... look at the back of your old board. A common problem is the solder on those two resistors goes bad from the heat they generate. Those resistors supply power to the relays.
