Carrier Weather Maker not turning on

rickvj · 10-24-2007, 01:51 PM

I have a Carrier Weather Maker and this morning I woke up to a 60 degree house. The thermostat was set to 68 for night time. I thought it was the thermostat at fault so I bypassed the thermostat on the control board and still nothing. I pushed the safety panel switch/pin and I saw a relay activate but the collector fan did not turn on. I walked away for a few mins and then went back and pushed it a few more times and the fan kicked on then the burner then the blower. I pulled the jumper off the control panel and it all stayed on so it's not the thermostat. I thought it was just a sticky safety switch and all was fixed so I put the panels back on. 5 mins later the furnace shut off then after a couple mins it kicked back on. It has been working normally for the last hour but there is still something wrong. I checked the vent and fresh air pipe and there were no obstructions.
Any ideas?

rvj

#CARRIERMAN · 10-24-2007, 02:30 PM

Hi rickvj

It sounds like you have a late 80's or early 90's furnace. This unit should have a board in it that has a number of CESO01157, or it could have a HH84AA021 circuit board. Both of these used a flat molex plug and were suceptable to moisture. Shut the power off to the furnace and remove the flat molex plug off of the edege of the board. This will be a white plug about 2 1/2" by about 3/8". Use a flashlight and look inside of it, if you see any corrosion. Get a cup that the plug will fit completely inside of, use a Coca-Cola classic and immerse the plug in it for about 15 min. Remove the plug from the cup and clean off the Coke with plain warm water. Let the plug air dry for about an hour. Make sure to check the mating surface on the board. You can us a dry tooth brush to clean this portion. You should be fine after that.

Good luck
Rusty

rickvj · 10-24-2007, 03:48 PM

Thanks for the info. That was exactly what the problem was. I pulled the Molex plug off the pcb and I could see where moisture had dripped right down the left most white wire contact and had been arcing. Half of the pad on the pcb had been arced away and the little 2wire contacts that are supposed to contact that pad weren't making it after I emery'd teh corrosion off. I built the contact back up with a little solder and plugged it back in and it works fine now. I am however concerned when looking at the burned pcb where the contact was and want to replace the whole thing. Is that white leftmost wire 120V or 24V?????? Also, where do I purchase the pcb? The local HVAC shops won't sell parts to you unless you are authorized. and the number you gave me is two digits off - my pcb is HH84AA015 not 021 - are they pretty much the same or what?

RickVJ

rickvj · 10-24-2007, 07:16 PM

Well, after a few hours of phone calls I found a local heating and plumbing contractor/supply dealer (besides Sears) who will sell parts to me the ordinary guy - not just other contractors, and they specialize in Carrier. I got lucky and they had a new main board in stock and it was 10 mins before quittin time so I was able to get over there and get the board before they closed. The only down-side of getting the part from them is they don't take returns. The up-side is I got the board installed in about 15 mins and it works fine plus the board was a newer model with more safety features and other stuff made to replace the older models.

Also, Carrierman - that model number you gave me is the PCB the contractor gave me.

Thanks for the help and saving me a couple hundred $$$$$$$

RickVJ

UKMatt · 10-25-2007, 10:24 AM

Having the same problem...thanks for the advice CarrierMan

#CARRIERMAN · 10-25-2007, 01:46 PM

Hi Again.

Glad to see you guys have your problems fixed. If you end up needing them, there is a wire harness still available for these furnaces. The last I knew you could get them online for about $20.00 plus freight. You would only need it if the connectors in the molex plug are corroded off. And as always I will help when I am available.

Good luck, have a safe and warm winter.
Rusty