22yr old kenmore upright freezer 253.9264211 cool but not freezing...why?

[mbed]

Greetings, all!

Have had this freezer since late 90s and need to keep it going for a bit longer. Currently it is cooling but not freezing the contents. Compressor runs most of the time (used to think it ran constantly until I heard it turn off briefly), Also, the compressor is hot to the touch while running. Freon lines don't seem to be warm of cool.  The upper opening inside the cabinet has a reasonable flow of cool but cold air coming out from it. There are no coils underneath or behind it that could restrict the heat transfer from the system. So, my thinking is either start capacitor on compressor (or compressor itself? how to troubleshoot which is problem?) or is it the defrost timer or thermostat more likely and could I test to find out?

Hoping to find a way to get it going for a few more years...many thanks in advance!

 

[Vance R]

If the compressor is running there should be cooling. Remove the evaporator cover to inspect the frost pattern. Let us know what your find.

[mbed]

Hi Vance,

Thanks for the reply! I never heard of the frost pattern so after looking it up, I found the it to be only on the upper left edge  of the assembly and only the left two-thirds of the uppermost row. Nothing on the rest. The fan was running strong. Also turned the thermostat down to off and unit stopped running. Turned back on and the fan is going again. 

Does this help narrow it down? Domo arigato!

Also, what is the best site to add an image to help describe it?

[Vance R]

With a small frost pattern like your description there is likely a sealed system issue. Leak is most common followed by a restriction in drier or capillary tube. At this point you would need to tap into the system to check pressure to verify.

 

No idea about which site to use for pictures. 

[mbed]

Hmmm, just when I was content to not have to learn how to do more things! 

The system uses 134a and I have done some auto ac dabbling and am preparing to do home 410a so I have a bunch of tools...I may give it a go.

Likeliest location for leak would be joints between tubing and devices then...any spots more likely than others?

Thanks so much for the info and help so far!

[Vance R]

Pull the insulation off the heat exchanger underneath in the compressor area. If it is all green with corroision one likely spot, other is the evap.  Get a bullet valve 3 in 1 to tap into load side for diagonstic purposes. If lowside is in a vacuum with compressor running add half the measured charge to confirm leak or restriction. You can also add uv dye to help in finding the leak.

[mbed]

Hi,

I did install a BPV and found the suction side to be at 20 in vacuum! So I added R-134 in steps, gradually getting it to ~1-2 psi. I added it in stages, over perhaps 30 min.  I let it run over night and now the frost pattern is nicely spread out over the entire (maybe only 80-85%, actually but much more than originally!) evaporator array. Still not frozen inside though.

I just saw your last reply. So the load side is the high pressure [aka warm] line? I have a tap on that as well and was planning to hook both of my lines from my gauges similar to auto ac work but haven't connected both yet due to the extremely low reading on the suction side. The label on the freezer says something about 140 psi on low side and 320 psi on high side. Shall I check the high side pressure and if so, should it be at 320 psi if properly working or is that typically as the upper limit?

I will check low side pressure again to see if it is holding also but may not be able to until later...so if it holds, what is next likely thing to check since the system was initially so low? And always, thanks again!

[Vance R]

2 hours ago, mbed said:

The label on the freezer says something about 140 psi on low side and 320 psi on high side

These are design pressures which are just maximum pressure used in testing only. Normal operation pressure are different. Usually lowside is around 0 and highside is whatever pressure that is around 20 deg f above ambient temp pressure from temp/pressure chart, example is ambient temp is 80 deg f the pressure of r134 should be 86.4 psi than add about 20 deg f and that pressure is 124.3 psi. So in this case lowside should be 0 psi and highside should be around 124 psi.

 

2 hours ago, mbed said:

next likely thing to check since the system was initially so low?

You have a leak somewhere in the system.  Depending on what tool you have available - electronic leak detector or add uv dye.

[mbed]

Greetings!

Good news is that the freezer is holding its freon at the proper ~1 psi on the suction line and freezing once again! It has been working for over a week now!  I appreciate your help and want to let you know the latest update and say thank you one more time!

[mbed]

Update with a question!

Still running well and keeping all things freezing! I lowered thermostat setting to two "clicks" from off. However, it still runs nearly constantly. What would be next likely thing to test or replace to lower the constant running?

Thanks again!

[Terry Carmen]

1 hour ago, mbed said:

Still running well and keeping all things freezing! I lowered thermostat setting to two "clicks" from off. However, it still runs nearly constantly. What would be next likely thing to test or replace to lower the constant running?

 

There may be air in the system. Did you evacuate it or just add gas?

[J5*]

It had a leak 

Did you fix the leak ?
 

its 22 years old , time to send it on its way 

cant trust it to keep food 

[mbed]

6 hours ago, Terry Carmen said:

There may be air in the system. Did you evacuate it or just add gas?

I only added the refrigerant, in small doses until the gauges read slightly positive on the suction side. I checked pressure maybe a week or so later and it was still at the same gross reading. Using dial gauges not digital so a small loss may not be discernable. 

 

2 hours ago, J5* said:

It had a leak 

Did you fix the leak ?
 

its 22 years old , time to send it on its way 

cant trust it to keep food 

I didn't fix a leak but was sorta' thinking the leak was rather slow...watching it's freezing performance every several days. It freezes well for over two months.

The cost of a new freezer, even though it would be more efficient and cost less to run, is more than I can spend. If it goes to the non freezing mode soon, I may try to search for a leak and fix it if feasible.

That being said, is there an easy way to determine whether the thermocouple or thermostat is bad? I did unintentionally verify the defrost timer was working when I noticed the glowing heating element near the evaporator when I first did the recharge and left the cover off to monitor the frost pattern.  I am wondering if the thermostat is merely functioning as an on-off switch...thanks again in advance to anyone and all!

[Vance R]

Easy tesy would tp measure the temperature in the freezer.

[mbed]

8 hours ago, Vance R said:

Easy tesy would tp measure the temperature in the freezer.

Everything is rock solid frozen still. I just wonder if the constant running is a failure of either thermstat or thermocouple (or internal equivalent) to turn off compressor after reaching a sufficiently cold temperature. Nearly everytime I check or open freezer, it seems to be running.