vintage air help needed

[johnny68]

well my vintage air system Sure fit for a 55 f100 3 years ago, is not getting cool at all. the gentleman that helped build the truck has the gages and correct freon and knows what hes doing, we hooked up the gages and it was 3/4 full after 2 years so we topped it off i have hardly used the ac due to the fact the truck has very little miles on it in 3 years. I know the heater control valve moves on and off with the switch,the compressor turns on with the switch i have a trinary switch for the electric fan but the ac doesnt get cold at all if any one could give some advise or guidance i sure would be greatfulthanks guys
john

[dhutton]

You can download troubleshooting instructions from the Vintage Air site. VA systems run at lower pressure than conventional systems and you have to be careful not to overcharge them or it will shorten the compressor life.

[dontlifttoshift]

Gauge readings would help.

Just curious, how did he know it was 3/4 full?

Donny

[johnny68]

hey Donny he has the gages dont know what they read he just mentioned it was 3/4 full?but when i get a chance ill go back over and hook them up if im correct they should read 160-240 high and 6-12 low right?
thanks john

[dontlifttoshift]

Yeah, that's pretty close. make sure the low side isn't fluctuating, the needle should hold pretty steady. The high side will vary with the electric fan being on or off.

Also check that the heater valve is actually closing. I know you said that the valve was moving with the switch but that doesn't mean its closed. You can check it with an infrared temperature gun. Another tell tale on the heater valve is that it will blow cold at first (while the engine is cold) and then warm up.

All of this is assuming that it blew cold two years ago and worked properly then.

[dhutton]

http://www.vintageair.com/download/Trouble.doc

[johnny68]

thanks dan talked to va the gentleman said he thinks reason low side pressure is high is due to heater valve leaking ill take off the heater hose and run ac see how it does
john

[johnny68]

well i took off the heater hoses just to be sure and there was no change and no cold air the high on the gages is 200 and low was 30 which i think the low is on the high side ill give va a call again tomorrow does anyone have any ideas?
john

[chops101]

I would suggest evacuating the system completely and recharging. Maybe moisture got in. Moisture is the systems' worst enemy. First though shoot some dye in the system and check for leaks.

And as for the heater solenoid, it will still blow ice cold with the heater valve open until engine reaches operating temp, so the heater solenoid was never a suspect.

[johnny68]

well we put the gages back on it turns out we have a leak the darn shrader valve went bad
john

[dontlifttoshift]

That makes sense, still don't understand how your guy knew it was 3/4 full.

Being that you have to evacuate the system I would replace the drier as well, it's only 30 bucks and it should be replaced any time the system is opened.

Also, when recharging, 1 pound 12 ounces of freon. That's all they need.

Glad you found the problem

Donny

[johnny68]

thanks Donny i appreciate the advise
john

[johnny68]

ok now the problem isthe compressor turns on for a second then stays off for 15 seconds trys to turn on for a sec then off for 15 almost like a cicuit breaker or relay any ideas?
john