Carrier Gas Furnace (forced Aire) blow only cold air

[Newsreader168]

Dear All,

2 days ago, my gas frunace started to only blow the cold air and the fan won't stop. A service guy come in and said the control boad is dead and charge me $400 to replac it. I decided to do it myself. I bought a new control board ( manufactured by Carrier, an compatible updated version) and replaced the board. However, still doing the same, fan won't stop and blow only cold air. I use voltage meter and measured that between the termnial R and W, 24 voltage. ( I have 6 terminals on the board, C,Y,GC,GH,R,W) and the wiring are, 1 on C, 2 on Y , 1 on GC, no wire on GH and 1 on R and 1 on W.

My thermostat is the RiteTemp programmable. It is working fine with my old board. However, after I installed the new board, when I closed the thermostat cover, ther is no voltage between the R and W on the board. If I left the thermostat cover open and measure the board R and W, 24 V. I left the thermostat cover open and put a paper clip to connect the R and W on the board, burner won't ignite. If I connect the R and the SEC1 on the board, I can ignite the burned (which is by pass the board). Can someone help me with this problem?

Thanks a lot.

Don

[Matt]

Don -

It's my opinion that furnaces do not fall under the DIY repair category. You've already learned one of the reasons why, and in the process you have already wiped out any money you hoped to save.

But, consider yourself lucky. You aren't dead (yet).

If you proceed down your current path, you are likely to find out another reason to let the pro's do the work: Bypassing controls for testing purposes will either kill you or damage something else, which can kill you later.

You now have a choice: continue guessing at what the problem is, or calling a service company to do the job right.

PLEASE STOP. The $$$ you think you may save will seem quite meaningless to those who bury you, or to you as you bury your own.

[Doug Kanter]

Matt, could you be a little clearer about what you're trying to say here? :-) :-)

(just kidding!)

[TURTLE]

This is Turtle.

i feel your waisting your band wide here. A Bought education is being tought here and your speaking prematurely.

TURTLE

[Matt]

Yes turtle, I agree. The fellow is learning a very costly lesson, but at this point - it's just money.

I'm not sure I am "waisting my band wide" however, as speaking after this chap has killed himself or his family is somewhat pointless.

[Bubba]

Damn! It seems that the $400 that guy was going to charge you isnt quite that expensive now, is it? Especially considering you probably cant take that electronic part back. At least if the $400 guy misdiagnosed it, HE would be eating it, not you. Now comes your big decision. Do you keep screwing with it, OR do you bite the bullet and get it done right? Decisions, decisions.......................... Bubba

[TURTLE]

This is Turtle.

A rolling stone down a hill gathers no moss and thoughts on the way. If there is any thinking going on , it will be when it hits the bottom of the hill and stops rolling. You just can't think when your on a roll.

TURTLE

[TURTLE]

This is Turtle.

For me to try to trouble shoot this set up over the internet is atleast a mircle to get it. Now with out a model and serial number for this furnace and thermostat it comes under mission impossible. With this said I will speak a little here.

1) Your working above your head on trouble shoot this set up.

2) You have a burnt ribbon between the Sec 1 & 2 to the R terminal and if you jumped out before from Pri 1 & 2 to R terminal. You put 120 volts on the 24 volt system. This usely takes the thermostat out but could just burn the ribbon between the R and Sec 1 . Now not knowing the model of furnace here it may have a 3 amp fuse in the board or other areas and you would blow it. And the possiblitys keep going.

3) There is a possiblity you have the wrong board or something is not wired up correctly. Did you read on the board instructs as to what furnace numbers the board will replace. It should be in the board paper work. Also check the board paper work for any conversion items to do with the listed furnaces.

4) You can have a tripped high limit on the heat exchanger and it will on some furnaces run the fan as a result [ but rare ] but usely will not break the Sec.

1 to the R terminal.

5) Well i can say there is only 74 possiblitys here and it is hard to list them without a model number to try to lower that number to maybe 21 with the model number and I'm right next giving up here. Well yes i give up.

6) You need to call the hvac service company to come get it straighten out for I give up. Sorry here !

TURTLE

[TURTLE]

This is Turtle.

Hey Bubba , What will burn if you jump Pri 1 to the R terminal , you know 120 volt to the 24 volt system ?

TURTLE

[Bubba]

Just about anything in its path. Bubba

[TURTLE]

This is Turtle.

Hummmm, New Board and thermostat I see.

TURTLE

[Matt]

Well, I can't argue with that.

You cajun bastards sure do have a different way of looking at the world! ;)