A thumping noise that stopped when the door was opened. Ultimately, it could no longer cool on either the fridge or freezer side.
The noise was the fan blades that move air over the fridge's evaporator coil thumping on an ice ball. This is located on the inside of the fridge behind a cover on the back wall. This coincidentally started after I turned on our whole house humidifier for the season. I kind of cranked it a little high as seen with excessive condensate on our windows the same day.
When I pulled the fan assembly out (just 5 screws and two plugs), there was more ice. One bigger chunk was where the capillary tube is brazed to the evaporator. I found that there was a pinhole leak there. I found it by melting the ice off with a hair dryer and then heard the hiss and felt it blowing.
THE REPAIR SCOPE
So, with that, here was the scope of the repair:
- Unplug it and let everything thaw out.
- Clean the back condenser coil and that area in general.
- Heat up the capillary joint at the evaporator to pull it out of the larger tube at the evaporator side.
- Cut the evaporator tube past the leak point.
- Stick the capillary tube in the evaporator tube and braze together without melting the plastic around it.
- Add a pierce valve in the back at the compressor to allow evacuating and charging the system.
- Evacuate the system for 30 minutes
- Charge the system.
We had put a $2200 refrigerator on order, but it wasn't going to get there for 4 business days. So, I went for it.
WHAT WE LEARNED
- You first have to get a license or have someone that does as well as equipment to catch evacuated freon and properly dispose of it.
- Brazing copper takes the same mojo as sweating copper water lines. It's easier and quicker since it so much smaller. The only notable difference is the braze rod material. It melts at a higher temperature. I pretty much just made the large tube glow red and touched it. I even let the rod get in the flame to help it along. No flux was needed for the rod.
- Even with a heat barrier, the hot air that rises can amp up to distort the wall. In particular, their is a lot of styrofoam lining that quickly melts. I didn't care since the refrigerator was old and came with the house - and we are moving. However, I definitely will get more heat barrier if I do it again.
- A good automotive AC kit with a vacuum pump works for this job. In addition, you need a piercing valve for refrigerators since they don't give any ports for servicing like an automobile does. The pierce valve gives you a good service port for the future.
- After evacuating and charging a little pressure, close the valves and unplug it. Ensure you don't have a leak still before you proceed. I did and wasted a can of refrigerant.
- You need less than a 12 oz can to charge a refrigerator - but you use pressure to know the limit. However, mine took one full can after evacuating. Online, most say 25-40 psi or to have it within the blue band of the gauge. However, my compressor took a 12 oz can and was only around 20 psi. So, I chose to stop there. The compressor sounded great (better than ever, actually) and cooled great as well, so I did not want to risk overcharging by charging to a higher pressure.
We canceled that $2200 refrigerator order and added the savings to our 83" OLED fund. In sum, if you already have mojo with sweating copper, doing refrigerator surgery will come with ease. If you already can service a cars AC unit, you'll be able to knock out anything a refrigerator can throw at you - more easily than under a hood. The bummer is the big inconvenience to your food supply while you gather your materials.