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Discussion Starter · #1 ·
AC was freezing up so I sprayed some Coil cleaner in it, as instructions say let it dry before turning on the unit.

Turned on unit and it kept cool for the better part of 16-20 hours, next morning it seemed their was no freon in the unit, it went dry.

Get a AC man out to recharge the system, it acted like it wanted to keep cool but now it seems to freeze up but startling part is, its only bottom half freezing up, top half seem to not get any charge or water to further cool anything as seen in these pics, anyone got a clue?


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First, if the unit needs refrigerant then there's either a leak or it wasn't charged right from the start. Refrigerant is not a consumable material and shouldn't need replacement.
What was the pressures, temperatures and superheat/subcooling when he checked it?
 

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Discussion Starter · #4 ·
He didnt check anything, but charged it but said Coolant was under warranty if it leaked out. Mainly because of the price of R22 I could only afford to really get it charged and he was generious to accept a couple hundred for the service.
 

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he said if it leaked out, he come out to replace the coolant for free but would have to fix the leak.

I dunno if thats what this is or not and why these small lines keep freezing the moment the unit turns on. Compressor issue?
 

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No, it's an issue with either the refrigerant charge, metering device or airflow.
As I said above, you don't just add refrigerant to the unit just because. There's either a leak or another problem going on.
Refrigerant doesn't just "get used up".
 

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It's not that baffling.
Reasons for frost/freezing issues-
Insufficient airflow
Incorrect charge
Metering device issue
Blockage
Clogged air filter
Outdoor ambient conditions too cold
Wrong refrigerant
Contaminated refrigerant
Wrong pairing of equipment
Indoor temp set too low
Low return air temp
 

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its baffling to me, like its not getting sufficient pressure to move the coolant up through the pipes into the coil further above.

perhaps clogged some how?
Has all to do with refrigerant temperature.

The temperature of the refrigerant going through the coil is proportional to pressure, has to do with boiling points.

Low pressure (not the same as low charge) makes the liquid refrigerant in the coil below freezing. The liquid refrigerant absorbs heat but stays at the same temp until it all turns into a gas, then the gas keeps on absorbing heat, physically warms up and gets above freezing.

Ice on part of the coil is a classic sign of not enough refrigerant entering the coil due to a restriction, leak, or metering device, or other problem.

Like roughneck said, superheat and subcooling tests must be done - those readings tell you exactly what's happening, if it's genuinely low, if there's another issue.

Ask the tech for them and if he refuses or seems baffled, fire this contractor. Without practicing or understanding the theory properly there is no way to troubleshoot this problem properly.
 

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Was this guy from a decent company, or just someone you found to come out cheap, or on the side?
You have to be careful with refrigerant charge as it can, quickly, cause irreparable compressor damage.
This isn't a hard issue to diagnose. But someone is making it very hard on you and your unit. A few simple readings and you'd have an answer in 10 minutes.
 

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Those pictures are classic signs of low charge. As it has already been said, there's other reasons for that to occur. Personally my bet is on low charge or less likely, that piston is plugged.

(I'd expect more uniform frosting and icing for many other causes)

Cheers!
 
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