Dash AC thermostat replacement

[lhaeb]

I have a sticking AC thermostat. The dash AC does not come on until I tap on the thermostat with the handle of a screwdriver. My diagnosis is that the thermostat is bad. I do not see how to change the sensor tube with out taking the whole evaporator case out. A local dealer says he will do it but the bill will be over $1000. There has to be an easier way to change the part without taking the evaporator out. I was thinking about cutting a hole in the case but then I am still not sure if I can install the sensing tube. Do any of you replace the part and how did you do it? I have placed this message on another forum but no replies. Thanks

[lhaeb]

Thanks for the replies. You gave me a new idea but jumping the tstat is the way I will go since I am the only one who ever drives the RV and I can easily tell when it is icing up if that will ever happy in an RV. I might also do this: I will buy a stat from anything and wrap the sensing tube tight around the suction line right where it goes into the evapator and wrap prestige tape around all of it. You guys saved me at least a $1000 bucks. Thanks again--my problem solved!!!

[dougrainer]

1. I will bet that dealer has NEVER worked on a National Dash AC system
2. Yes, on a National, the Evap housing is difficult to get too. Removing the RF headlamp assbly(about less than 1 hour to pull and reinstall) gives easier access to the tstat. You do NOT have to remove the old sensor, if it is not easy to remove. You can drill a small hole in the evap case by the evaporator and install the sensor tube in that hole and mount the tstat on the firewall.
3. As another poster stated, it is really a freeze sensor and as he also stated, on a Class A motorhome the odds of the evaporator freezing is almost impossible. So, you can jumper that tstat and go on your way. Doug

[Ranger_Smith]

That is a freeze sensor. You can take it out easy and just carefully pull out the copper tube. I did mine. I don't know if it is actually needed as I have never heard of a vehicle AC freezing up. I jumpered mine until I could get another one. This was on our W24 chassis when we had it.