Ac update?

79jasper

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Someone updated my F250s system and it was cold when I got it. After a few years it wasnt cold anymore. 2 cans of $5 R134a from Walmart got it back to just below "full" on a cheapo hose/gauge and it's cold again.

My RV has the conversion fittings too, but it has zero pressure in the system now. Now, it could have been 20 years since it was last filled so maybe it just needs a vacuum pulled and 4 cans to get it back to being good, but eh... I don't drive it around in hot places enough to justify messing with it. Maybe some day?
Does help for defogging your windows though

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franklin2

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Really? I had no idea what they ran for freon in them. I guess I learned something today.

Some of those units ran r22 also. You don't know what you are going to run into with those smaller 120v units.
 

Cubey

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Does help for defogging your windows though

Being a motorhome, the windows get soaked with water from me and my dog being inside. Plus I run an unvented Buddy heater. (Yep, I crack a window and have a battery operated CO alarm) so I end up just having to use a large towel to dry off the inside of the windshield and the side windows. I use "damprid" types of products to help with moisture too. I often get the ones from Dollar Tree since they are cheap and I can place several around in different places. No electricity needed like with a dehumidifier.

Some of those units ran r22 also. You don't know what you are going to run into with those smaller 120v units.

Whatever was common in 1985 is what it has. It still blows cold, so I'm happy. It's probably the most heavily used thing on the motorhome too since the guy I got it from lived in it in an RV park in Oklahoma.
 

junk

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When I convert a system. I start by looking for leaks. Normally by pulling a vacuum and seeing if it holds at all. Then start fixing seals at the greasy ac connections. I always put UV die in my AC systems. So if I have trouble again I can find the leak. In my trucks I run red orifice tubes. I have great AC temps. 42 degrees out the vent. New AC parts for these trucks on rock auto are dirt cheap. So replacing hoses and stuff is not cost prohibitive. Heck a Brand new AC compressor kit for my 93 serpentine truck was under $150 bucks. I use a compressor ran venturi vacuum pump. I only work with R-134A refrigerants.

$50 in tools and a person can do a pretty good DIY AC repair.
 

chris142

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When I convert a system. I start by looking for leaks. Normally by pulling a vacuum and seeing if it holds at all. Then start fixing seals at the greasy ac connections. I always put UV die in my AC systems. So if I have trouble again I can find the leak. In my trucks I run red orifice tubes. I have great AC temps. 42 degrees out the vent. New AC parts for these trucks on rock auto are dirt cheap. So replacing hoses and stuff is not cost prohibitive. Heck a Brand new AC compressor kit for my 93 serpentine truck was under $150 bucks. I use a compressor ran venturi vacuum pump. I only work with R-134A refrigerants.

$50 in tools and a person can do a pretty good DIY AC repair.
Pressure testing and using soapy water is much better at finding leaks than a vacuum test. A vacuum test can actully suck a leak closed. Federal regs say to pressurize the system with nitrogen to a minimum of 100 psi.

I use 200 psi.
 

junk

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I've shot compressed air in them to help find leaks before, but I don't have a hose made to connect compressed air to my a/c gauges. I'm also not excited about introducing contaminants from compressed air. So using vacuum is simpler for me. I'm not a professional so I don't have nitrogen handy either.

Not saying vacuum is the best way, but it's been working for me.
 

chris142

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You can put a filter on your air line to stop the water. May want to do that.
 

Philip1

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I've shot compressed air in them to help find leaks before, but I don't have a hose made to connect compressed air to my a/c gauges. I'm also not excited about introducing contaminants from compressed air. So using vacuum is simpler for me. I'm not a professional so I don't have nitrogen handy either.

Not saying vacuum is the best way, but it's been working for me.

just so you know it can also be potentially dangerous to use compressed air to pressurize an ac system. Under normal circumstances r134a is not flamable however when mixed with air under pressure it becomes flamable. Usually all the refrigerant is removed before it becomes pressurized however there is still the risk there might be some left over. This is why its recommended to use nitrogen when pressure testing systems
 
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