Ac trouble

[Willie T]

I have a 2017 Fuzion Chrome. The T stat wire from thermostat to the control unit in the ac (R+) is bad. Anyone have a suggetion on how to pull new Termostat wire from as unit to wall mount Thermostat????

[ctbruce]

Not really. Is the wire bad broken or bad shorted out?

There are several electricians on the forum who are super helpful.

[Willie T]

Not real sure if it is shorted or a break, I don’t have 12 v at R+ on control box. We did a external jumper wire between R+ and Thermostat and now we have the 12v required for normal operation. Thanks for any help

[xrated]

On my Fuzion Impact 303 I just recently added a second A/C unit, and put it in the garage area where the trailer was pre-wired for it. When I did that install, it seemed to me that the wiring that went from the overhead electrical work box by the vent, over to the wall where I was going to install the thermostat was not secured. In other words, possibly just laying up there between the ceiling and the insulation/roof. I've said all that to say this. If you know for sure that the wire is bad (open, shorted, grounded, whatever) and you need to put a new one in, carefully disconnect the wiring on both ends (at the control box and the thermostat) and see if you can pull on one end or the other.....and the other end moves! CAUTION.....WHEN TRYING THIS, MAKE SURE THAT WHEN YOU TRY TO PULL ON THE WIRE/CABLE...MAKE SURE THAT YOU DON'T PULL IT UP INTO THE ROOF WHERE YOU CAN'T GET TO IT. YOU WILL USE THIS WIRE/CABLE TO PULL THE NEW ONE IN. If this is the case, it probably means the wire is NOT secured anywhere on the run between the control box and the thermostat. If that's the case, buy a new piece of thermostat cable (several feet longer than what you think you will need) and serve it on the end of the existing cable, then with a helper possibly, slowly and gently pull the new wire/cable in. A couple of cautions here......

1. Do not try to "force" the pull. If it gets tight when pulling, stop and pull back the other direction and then try again....kind of a back and forth type thing. That may free up the cable to be pulled the rest of the way.
2. When serving the new cable onto the old cable, strip at least a couple of inches of insulation off of the wires and make a loop and wind the wire back around itself. Then take the new cable that you bought and strip a few inches of insulation off of those wires and put them through the loop(s) that you made in the existing cable and wind the end around themselves on the new one. That will give you a very solid connection to be able to pull the new cable through and over to the other end. BEFORE you try and pull that "knot" anywhere, take a roll of electrical tape and very tightly tape from one end to the other of your know or splice till it is completely taped. The idea here is to completely cover the joint that you made so that it doesn't leave any edges to get hung up on when pulling.
3 Take it slow and easy.......using a light touch when pulling. It generally is helpful to have someone at the other end and "feeding" the new cable up and into the hole in the wall where the thermostat was. Make sure the wire/cable isn't twisted as it goes into the wall, and of course no sharp bends in the cable. If you get to a point that it will not move anymore and is hung up....try the back and forth several times. If it will still not go through, it's time to pull the original wire back to the starting point and stop. At that time, you may have to take a different approach to the wire pull.

Let us know what you decide to try.

[chuckster57]

More often than not, thermostat wire is 7 wire. If all colors are not used, just switch to a different color.

[JRTJH]

More often than not, thermostat wire is 7 wire. If all colors are not used, just switch to a different color.

And add a piece of tape on both ends marked with the original wire color. That way, next year when you or a serviceman notices that the "orange wire is disconnected" it'll make sense when the tab says "ORANGE" on the white wire that is connected..... BTDT many times. The future will thank you for keeping things clear.

[xrated]

The older camping trailers probably have the 7 conductor cable because they had an analog thermostat, but the newer ones are more likely to have a 4 conductor wire. This is because most all of them now use digital thermostats and those generally require a +12V, a -12V, and a communication (comm) wire. The +12 goes to the control box and then the control box has a terminal for th R+ to go to the thermostat. The -12v goes to the thermostat and to the control box, and finally, the "comm" wire goes from the control box to the thermostat. This is the wire that transmits the digital signal from the thermostat to the control box to tell it what to do.....heating, cooling, fan speed, etc.

So, there is a possibility that the O.P.'s thermostat cable does in fact have an extra wire conductor in it that is not being used (should be taped off on both ends...maybe). It that's the case, he could swap out the R+ wire that is bad with the wire that is not being used and get lucky. I guess I would be concerned with "what happened" to the existing R+ wire that it is not working any longer. Was it damaged? A screw or nail put through it? Pulled too tight? In other words.....are the other wires in the cable possibly damaged also and headed for failure at some point in the future? Maybe!

Myself, if there were one damaged wire in the cable, I would pull it out and pull in a new wire/cable to possibly head off future problems. YMMV!

[flybouy]

I have a 2017 Fuzion Chrome. The T stat wire from thermostat to the control unit in the ac (R+) is bad. Anyone have a suggetion on how to pull new Termostat wire from as unit to wall mount Thermostat????

Have you confirmed it's the wire? i.e. voltage apparent at one end and not the other? Have you checked to see if the loss of connectivity is close to one end or the other? I'd think thats where it would be most prone to flewing. If it is broke in an unacessabile area, then most likely the rest of the conductors will fail as they are all subjected to the same forces.

[chuckster57]

The older camping trailers probably have the 7 conductor cable because they had an analog thermostat, but the newer ones are more likely to have a 4 conductor wire. This is because most all of them now use digital thermostats and those generally require a +12V, a -12V, and a communication (comm) wire. The +12 goes to the control box and then the control box has a terminal for th R+ to go to the thermostat. The -12v goes to the thermostat and to the control box, and finally, the "comm" wire goes from the control box to the thermostat. This is the wire that transmits the digital signal from the thermostat to the control box to tell it what to do.....heating, cooling, fan speed, etc.

So, there is a possibility that the O.P.'s thermostat cable does in fact have an extra wire conductor in it that is not being used (should be taped off on both ends...maybe). It that's the case, he could swap out the R+ wire that is bad with the wire that is not being used and get lucky. I guess I would be concerned with "what happened" to the existing R+ wire that it is not working any longer. Was it damaged? A screw or nail put through it? Pulled too tight? In other words.....are the other wires in the cable possibly damaged also and headed for failure at some point in the future? Maybe!

Myself, if there were one damaged wire in the cable, I would pull it out and pull in a new wire/cable to possibly head off future problems. YMMV!


Not to argue, but I’m working on a 2019 Solitude. Digital thermostat (AirXcel) and it has 7 wires, not all are used.

[xrated]

Not to argue, but I’m working on a 2019 Solitude. Digital thermostat (AirXcel) and it has 7 wires, not all are used.

Hey Chuckster.....I'm sure some of them do still use the 7 conductor cable....maybe they are using up their stock or inventory......or.....they may just not be smart enough to know that they don't need that many conductors to make them work....who knows? :D

[JRTJH]

Hey Chuckster.....I'm sure some of them do still use the 7 conductor cable....maybe they are using up their stock or inventory......or.....they may just not be smart enough to know that they don't need that many conductors to make them work....who knows? :D

Or it could be that the 7 conductor is 8 cents a foot and the 4 conductor is 15 cents a foot when they did their last contract buys...... Knowing how "cheap" (don't think that's a bad thing to say) that Keystone is, they'd do anything to save a penny......

[ChuckS]

Trekwood shows that year with a 4 wire com cable. I wonder if one of the connectors is bad or broken wire right at connector. I’d cut back six inches or so and see if their is power there. If so get a new 4 wire connector and crimp tool