dash air

[captainron]

I have a Evans Tempcon Dash Heater AC unit. It blows cold for approx 10 min then gradually starts blowing hot air. (even in vent mode). System has been recharged but same problem. It is as if I am gradually turning on the heat. Any ideas (thermostat, vacuum ???)
Thanks

 

[Triple E]

Re: dash air

Hello, I am not sure what the Evans Tempcon is. Do you change you temperature with a slide arm or is it digital? If slide arm, you may have a weak cable that is not keeping the AC control lever in the correct position. Have you tried going to HOT and see if the heat will gradually turn cool? I also had this problem with my AC and it was caused by the cable. The clamps that hold the cable into postion, two of them had broke. With these two clamps broke it caused a weak point in the cable. Replaced the clamps and all is well. The bad part, these clamps are under my dash and replacing them was not easy. -Steve

 

[captainron]

Re: dash air

Thanks for the info. I have a rotary switch cableless. It is electronic. I think I found the problem. I tap on the heater control valve on the firewall and it starts blowing cold air again. It appears that the valve is sticking as I have tryed this twice and it worked both times. Apparently this is an issue with my type of hvac system. A RV mechanic stated he replaces these all the time. I am attaching a troubleshooting pdf for any one who wants to check there system out.
Sorry file to big to attach. Anyone who wants it can email me rbbaker@telus.net :approve: