A/C no bueno

Is the a/c comp. locking up soon after you have a new one put on every time, lf yes the 1st one that blew up put powered metal in the whole system and is hard to get out of it?

 

Well, thats a vote for doing EVERYTHING at once then, not a guarantee everythings fine, but stands the best chance of lasting trouble-free

 

They sell a gal. Of cleaning solution that if you take the line off the comp. And off the dryer and run some of the cleaning stuff and plug both ends and let it go back and forth a few times and put it in a clean jug then look at what came out, lf it is dirty and has shiny metal shaving in it, that's all you need to know that the whole system will need to be cleaned and condenser will have to be replaced because there is no way to clean it, but evap. under the dash and one in under bunk can be cleaned,
new rubber lines can be made and steel lines can be cleaned by letting cleaning sol. Sit in them till it comes out clean, there's no need to keep putting comp. on now that you are paying for them.

 

My experience is the same. Replaced York compressors almost every year on 2 different Trucks, over 15 yrs. time, only 1 lasted 3 yrs. Last time, I went 2 hot summers doing research on swapping to a Sanden. I took everything apart. I flushed evaporators on the bench with water hose, for over an hour. Also used the flush fluid, air hose. Let everything dry. New condenser, expansion valves, and dryer. I should have replaced the evaporators, they never came totally clean. My Freightliners evaporators aren’t a closed loop. Header and fin design, same as condensor. Impossible to fully clean. I replaced my Sanden compressor after one year. Only because I thought it was low, and in a hurry put a can of Freon in upside down as liquid. I’ve done it a lot with the York’s. I’ve always heard it’s not good to do. I split the compressor, it cracked open. Guess it’s true, Lol. I replaced it, along with a bad high pressure switch. Systems been good for 3 yrs. now. My first Truck had a Sanden, it lasted 1 million miles.

 

I use to have a good ac guy and the shop closed, he moved to a closed shop, no outside work allowed.
Ac didnt work a mi th ago, had them go thru it, it was low in charge and they couldn't find the leak. Refilled it off I went.
Lasted 1 day, died. Dropped the truck, theg said the compressor split wide open and I needed a new one. Ordered it, came In, replaced, went to pick the truck up, the main line to the condensor was leaking. They ordered the line, i asked if they were changing the dryer and expansion valve, was told they should be replaced, they said dryer only.
Finally got it back, it works great until it gets REAL hot out, then the fan cycles endlessly. It's on more than it's off all day yesterday and today. When i idle i can smell something and the ac is noticeabley warmer.
Back to the drawing board...

 

If it happens while running or idling. It may be overcharged a bit. If it blows hot idling, and works running down the road, fins on condensor or radiator may be blocked. While idling, normally the fan kicks on, due to high pressure, pulling air in across the condensor to cool it down and lower pressure. Then, maybe 5-15 seconds later the compressor clutch cycles off, due to high pressure. Once pressure drops, fan goes off, and compressor engages again, then the process repeats, not always exactly the same amount of time, but pretty close. That’s normal. Ideally the clutch on compressor will stay engaged twice as long as disengaged. It can on a real hot humid day cycle on 60% and off 40% of time. Even 50/50 sometimes. I like when the compressor runs (on high idle) for close 60 seconds, and cycles off, close to 30 seconds. While the fan engages and disengages pretty much opposite of compressor clutch engaging and disengaging. Usually, if it’s cycling on and off, (short cycling) it’s overcharged, And the high pressure switch is working. If it’s running all the time, without cycling off, it’s usually undercharged, or the high pressure switch is bad. Sometimes it will still cool good, especially since it’s running constantly. But being low shortens the compressors life, due to compressor running hot. Compressor needs enough Freon to cool itself. If it’s running constantly, and not cycling off when engine fan is coming on, you may have a bad high pressure switch. That’s what my problem was, when I split the compressor open. It can still work, with a bad high pressure switch by running it low on Freon, low enough to not blow a hose, while compressor runs constantly, and the fan runs more trying to lower the pressure, or it’s engaged manually, running all the time. Replacing the high pressure switch is easy if it’s on the dryer. Dryer has a schrader valve on it, you won’t lose any Freon. That might just be your problem. I used to fill mine without gauges. I’d fill it till the compressor cycles off, then stop. That usually worked good. As long as there no obstruction in the condensor, or radiator behind it, while idling both the compressor and fan should cycle roughly opposite of each other, like I described. If the compressors not cycling, running constantly. First I’d change the high pressure switch. Just to be safe, and avoid overcharging and splitting the compressor. Then observe, and if the compressor cycles off, check the difference in the time compressor is cycling on and off. Short cycling often usually means it’s overcharged, staying on constantly usually means it’s undercharged. If needed, while adding Freon if it starts short cycling, it’s overfilled. A little bit can make all the difference. Give it plenty of time to circulate, and balance out while adding Freon, before making a final judgement based on cycling time and operation of the compressor and fan. When it’s just right, compressor will stay on about twice as long as it’s off, fan will also operate while compressors off, till it kicks back on. It should operate almost consistently while idling. Don’t forget to check if it’s blowing cold. Lol.

 

Awesome!! Thank you!!