Rear furnace won't come on

[Russ & Dana]

I have a 2000 dolphin 5373 by national

It has two air conditioners and two furnaces

the rear heat will not come on, when i turn it on at the thermostat there is a clicking in the rear air conditioner. The furnace is on the floor in the rear.

I have taken the filter to the air cond off and there is a box there where all the electrical wires go into. (square metal box) and i can feel the clicking inside the box.

There is also a phone jack connector that is on the outside of the metal box when i disconnect the phone cord the clicking stops and starts again when i plug it back in.

Any help would be appreciated, as i sure hate to take it to the dealer

Thanks
Russ

[Theberrys]

Russ

The phone line is the data line fron the Comfort Control Center (Thermostat). So removing it stops all communication and the demand to turn on the furnace.
The clicking is the relay on the electronic control board in that box. The A/C unit turns on the furnace. Remove the cover from the metal box and look for two wires that will be labeled furnace on the silk screen of the board. Pull them off and touch them together, if the furnace starts then the electronic control board is faulty and needs replacement. If the furnace doesn't come on, and I can't imagine with the clicking this would happen the fault is in the furnace, but that doesn't account for the relay clicking. You might try replaceing the relay but soldering is required and it's just a guess without further testing.
Here is a picture of how the two A/C units and the furnaces are installed. Also a picture of the circuit board wiring to see where the furnace wires are connected. Look on the left side.

[Russ & Dana]

Quote:

Originally Posted by Theberrys Russ The phone line is the data line fron the Comfort Control Center (Thermostat). So removing it stops all communication and the demand to turn on the furnace. The clicking is the relay on the electronic control board in that box. The A/C unit turns on the furnace. Remove the cover from the metal box and look for two wires that will be labeled furnace on the silk screen of the board. Pull them off and touch them together, if the furnace starts then the electronic control board is faulty and needs replacement. If the furnace doesn't come on, and I can't imagine with the clicking this would happen the fault is in the furnace, but that doesn't account for the relay clicking. You might try replaceing the relay but soldering is required and it's just a guess without further testing. Here is a picture of how the two A/C units and the furnaces are installed. Also a picture of the circuit board wiring to see where the furnace wires are connected. Look on the left side.

Thank you so much, I will do this and see what happens,

Info like this and the kindness of so many forum members make this forum a great place!


Thanks to all!

[Kevin H]

I had a problem with the front heater in my 99 dolphin 5370. I thought it may have been the control board. I took the two control boards out of both front and rear furnaces and switched them. The rear still worked fine but the front stayed the same. I put them back to the original configuration and the problem persisted. That showed me the problem was not with the board.

You might try switching yours and see what happens.

I then undid all the connections, cleaned them with electrical contact cleaner and reconnected. I used a pair of needle nose pliers to gently compress the connections and Viola!!! The front started working!!

Apparantly there was a weak or dirty connection somewhere. I STRONGLY suggest you take a digital close up of all the wires and connections prior to undoing anything. There a number of wires and plugs. A color picture will save a lot of headaches () when hooking everything back together.

Good Luck and Happy Trails!! -- Kevin

[Russ & Dana]

Quote:

Originally Posted by Kevin H I had a problem with the front heater in my 99 dolphin 5370. I thought it may have been the control board. I took the two control boards out of both front and rear furnaces and switched them. The rear still worked fine but the front stayed the same. I put them back to the original configuration and the problem persisted. That showed me the problem was not with the board. You might try switching yours and see what happens. I then undid all the connections, cleaned them with electrical contact cleaner and reconnected. I used a pair of needle nose pliers to gently compress the connections and Viola!!! The front started working!! Apparantly there was a weak or dirty connection somewhere. I STRONGLY suggest you take a digital close up of all the wires and connections prior to undoing anything. There a number of wires and plugs. A color picture will save a lot of headaches () when hooking everything back together. Good Luck and Happy Trails!! -- Kevin

Thanks

I will try that,

I haven't had the time to work on it yet but in the next few days i will
Thanks