reply re schematic

Grady,
I would have liked to attach the images however I cannot seem to. I noticed below that in the posting rules that I am not permitted.

This is the schematic for my furnace's board. Note that I indicated my furnace model as Carrier "Lowboy" 58CLA - 120 series (oil) which is incorrect; The model is 58CLA-105. It is also referred to as the Comfort 80.





I thought it might also be wise to insert the wiring diagram for the power venter as well.



I have noticed as well that everywhere I look, there is mention of jumping the TT connections on the primary. While I am not proficient at reading wiring diagrams nor understanding a lot of the jargon, I see that this is not the case on my furnace. Could this possibly explain why this is happening? I also wonder if this could have perhaps explained the meltdown of the previous board.

I was away for a couple of weeks during which time the board fried. Would a constant call for heat while in lockout possibly provoke this? Regrettably I do not know what the component might be but on the drawing it is one of the two somewhat t-shaped black modules. I suspect they are relays but...

 

Is it a picture or .img file? See if this helps.....http://forum.doityourself.com/electr...your-post.html

 

So did you put a new board in yet? Or are you afraid to? And if you haven't - what are you doing for heat?

I presume you have no clue as to what even sequential problems occured since it took out the board before you could find out? It would indeed be scary to buy another, stick it in, and have that one fry right on the spot. This would require a lot of checking for any short. I doubt any simple over-running would cause such a problem, by itself. Certain things are simply supposed to switch over to some other circuit. Every circuit is designed to handle given power loads, with no prerequisites. It be like wondering if your space heater ran too long endlessly, if it would burn up = no. It would be irresponsible to make such stuff that had ifs and and buts attached.

Do you see anything obvious in the furnace like water stains on/around the board? Or anything where any of the components of the board arced over to sheetmetal because it is mounted so close? My next door neighbor, who I replaced his board for, had that happen - it arced from wome resistor looking thing, to sheetmetal, like a tiny fraction of an inch a way (bad design). The new board I put in for him was reconfigured by the OEM, and the resistor things were no longer close to the sheetmetal like that.

 

http://www.docs.hvacpartners.com/idc.../58cla-5si.pdf

Looks like the yellow (pin 6) wire and the blue wire (pin 3) connect to T, T.

I recommend getting this repaired by an HVAC contractor.

 

Ecman,

Yes, the new board is in place. Despite that, I then had other issues that arose and due to the extremely messy installation, I through in the towel and hired a new contractor to re-do all the wiring (of which most connections were poor).

To this, I would add that 4 uselless relays were removed and the wiring now conforms to code as well as what one would expect in a well done installation. I did cost me big bucks but I now have regular heat in below 0 weather.

Thanks for your input.

 

Houston, Thanks for posting the schematic for me. I did bring in a contractor to handle this since the entire initial installation was a mess. Thanks to you and all others for your time and efforts to help me.