Charge Your Own 'Fridge?

[Lost_in_the_HTTP]

Long, long story of multiple problems over the years that I won't get into. 21CuFt Top Mount Freezer.

Had a fridge tech out several years ago that said coolant was low and topped it off. Said the telltale is the icing on the low pressure side of the coil behind the panel in the freezer.

Once he did that, it's worked fine for 4 .. maybe 5 years now. But over the last few months it's been showing icing again. I've been able to manually defrost it a few times and it works fine again.

So, instead of buying a new fridge and taking on who knows what new problems, or paying somebody $100 or more for 15 minutes work, I'm wondering if it's worth it to try it myself. R134 is cheap and the manifold kit is about $50 or less from HF.


But not having done it before, I don't need a can popping open in my hand.

 

[herm0016]

you have to pull a vacuum on the lines, and then fill it with a precise amount of gas to make it work correctly. are you going to also purchase a vacuum pump, proper gauges to check that it pulled correctly and a precise scale to weigh the can while charging it? and solder in a new dryer, to do a proper job.

 

[snoopy7548]

If you have to keep recharging your refrigerant, that could mean you have a leak which should be repaired (if possible). I would just buy a new fridge if it's out of the warranty period.

 

[mindless1]

you have to pull a vacuum on the lines, and then fill it with a precise amount of gas to make it work correctly. are you going to also purchase a vacuum pump, proper gauges to check that it pulled correctly and a precise scale to weigh the can while charging it? and solder in a new dryer, to do a proper job.

Technically that is the "right" way to do it, but in practice you can just add a little refrigerant, wait, add a little more till the system is operating properly. A repair tech won't tell you that because 1) Job Security, and 2) They can't keep coming back for a few minutes to top it off then wait to observe the result, have to finish while they're there and move on to next paying site.

Main thing is, don't overfill. However the leak may have increased, or a new leak somewhere else. Getting 4-5 years last time, may or may not suggest an equal extension of use this time.

Manifold kit, see if it's available as a loaner from an auto parts store.

 

[herm0016]

Technically that is the "right" way to do it, but in practice you can just add a little refrigerant, wait, add a little more till the system is operating properly. A repair tech won't tell you that because 1) Job Security, and 2) They can't keep coming back for a few minutes to top it off then wait to observe the result, have to finish while they're there and move on to next paying site.
Main thing is, don't overfill. However the leak may have increased, or a new leak somewhere else. Getting 4-5 years last time, may or may not suggest an equal extension of use this time.

and you are just releasing more r134 a into the atmosphere with a global warming potential 1430x that of CO2.

 

[mindless1]

^ Nothing you stated previously changes that since you did not include "find/fix leak", which over a few years may just be the compressor seal. R134 inherently leaks after years.
I didn't design and put it in in the first place, am not the one causing it to leak out. Every consumer that buys a refrigerator, A/C, vehicle, etc. with r134a is to blame, or the manufacturer, whichever.

However, I am not against the trivial level of global warming caused by a little r134a, because of the orders of magnitude lower levels and it breaks down in 10-15 yrs. GONE. CO2 is a larger problem.

 

[Lost_in_the_HTTP]

Still working, so whatever leak there might be must be very small. It's just having trouble keeping up with warmer weather and it frosts up pretty bad at one end of the coil, which I'm told is a sign of low coolant. It gets cold enough to make ice, but it just runs longer and more often which runs up the electric bill.

Last service guy (several years ago) put a tap in one of the lines so he could charge it. If I knew what to do, i could use that same tap and probably one or those cans of R134 at stores would help.

I just don't want the can to split open in my hand.

 

[mindless1]

Get refrigerant with UV dye in it and then a UV light to find the leak.

I don't understand "can to split open in my hand". Why would it split open? Wear gloves? It's a pressurized can, like spray paint, have you had past life experiences that cause worry over any pressurized can of xyz? There may be something I am overlooking...

 

[Lost_in_the_HTTP]

^^^ There have been stories about AC cans bursting if they get hooked up wrong. Pressure is put into the can instead of taking coolant out.

 

[mindless1]

^ Then don't hook it up wrong? I'm guessing they hooked it up to the high side instead of low?

 

[Lost_in_the_HTTP]

Exactly my point. I gotta know which side is which, which I don't.

 

[mindless1]

The low pressure side is between the evaporator and the compressor, with the evaporator being the cold coils inside, rather than condenser coils which are on the rear, or under it near a fan.

You stated someone has previously topped it off, and put a tap in. There you go, that's the low side. There are no add-on taps when it came from the manufacturer.

As always a youtube video might help or search youtube for others recharging refrigerator freon 134A etc search terms. In the video he's calling it the "suction side" instead of "low side".

 

[Steltek]

If you are going to recharge it, you might consider adding some UV dye to the system (i.e. the same stuff they use on vehicle AC systems) as it might allow you to find the actual leak.

 

[Lost_in_the_HTTP]

I only see one tap though. I was thinking he added one and the other was already there, but if so, I can't find it. Would I only need the one?

 

[mindless1]

You only need one tap, on the low side between the evaporator and the compressor. Something already there from the manufacturer, would be a valve brazed onto the line, not a bolt-on clamshell that pierces the side of the line.

 

[Lost_in_the_HTTP]

This one is added, clamshell pierced. No room right now to get a picture.

The big black ball is the compressor, no? Line comes off there and goes up into the box. I think.

 

[mindless1]

Yes, pics would make it 100% but the big black ball is the compressor. You have the right valve if it's between the compressor and the coils going into the cold compartment.

Something I should have mentioned already, is if you have a gauge hooked up, you can see what the pressure is before you open the valve to the can of refrigerant. Low side is going to be between 0 and ~4PSI, high side is going to be 100+ PSI, so if you were accidentally hooked up to the high side, you simply don't open the valve to the can, but from your description it sure seems like you have the valve on the low side which it would have to be, to add more last time.

 

[Lost_in_the_HTTP]

I was thinking about going this way:

R134A A/C Manifold Gauge Set

Amazing deals on this R134A A/C Manifold Gauge Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

$60+


But if all I need is the Low side, maybe I only need this?

Advance Auto Parts - Down for Maintenance

$25

 

[Lost_in_the_HTTP]

But as I was looking at that, I remembered I might have a can of coolant. Out to the garage I go to look for it and I find this:



The one can is sealed, new. The other still has weight and shows no sign of leakage. This is at least 10 years old, bought for a car that has since blown an A/C hose that I never bothered to have repaired.

Do I already have what I need? Will the oil and leak seal be a problem?

I'm guessing this is the low side tap?





Yes, it's dusty and nasty, but it's behind the Fridge, so who cares?

 

[Lost_in_the_HTTP]

Gotta read that sheet included ... can't recall if I want the can up or down.

 

[mindless1]

The can goes up. You are putting the vapor from the liquid into the system, a little at a time. Upside down, straight liquid could be more than the compressor can handle at once.

Yes that looks like a tap but I can't tell from the pic, where that line goes, can only assume it's on the correct side. Follow the line to see if it goes to the evaporator.

Yes you might already have what you need and can use what's left in the partial can to start, maybe finish.

Whether any of those hookups works, depends on whether they fit the tap fitting or need an adapter. Another choice is a loaner tool, just put down a deposit and return it when finished. Example, but again I don't know if it fits your fitting or you'd need an adapter:

https://www.autozone.com/loan-a-tools/loaner-a-c-tool/p/oemtools-a-c-manifold-gauge-set/326077_0_0

Some people worry about the leak sealant causing clogs, but on the other hand if you have a leak it might help. Your call, I'd prefer not to add sealant unless it's a fast leak, then it may be beyond salvaging anyway unless the leak is properly repaired.

 

[Lost_in_the_HTTP]

It goes along the bottom and then up into the unit, follow the blue line. There is a smaller tube wrapped around it that goes to what may be a thermocouple (big bulb thing). That's the low pressure line?

Then the other line (marked with red) would be the return high pressure?

There's one more (marked with orange) that looks like it comes out of the compressor a couple of inches and is crimped off.

 

[mindless1]

Yes, then the tap is on the low pressure return. Another hint is it looks like a larger diameter pipe, which the return would be if one or the other. Only the low pressure side is called the return (or suction), because the compressor draws from the low side then pushes it out the high side.

 

[Lost_in_the_HTTP]

In other words, my arrow heads are backwards of the intended flow.


And can upright, vapor ... OK.


Good so far I guess. Not sure when I'll get up the nerve to try this.

 

[mindless1]

Maybe while the fridge is pulled out to take the pics?

It will be okay. If you lose a hand you'll just be typing slower to tell us about it.

Kidding aside, I would wear gloves, in case something leaks.