Hello! I think I'm in the right forum....

Hello! Thank you for the reply!  When it's plugged in it does run but it does not cool.  We thought maybe it was low on coolant.  We were scared to try anything because my parents always said it was ammonia powered.  I feel like it's related to an incident were the door didn't get shut completely and it wasn't caught until the next day.  It defrosted completely with water everywhere.  It was cleaned up and dried out but after that it didn't get cold again.  

Hi and welcome! As Travis explained, the FEA you have does not have any sort of toxic refrigerant. It has a small charge of R12, which is relatively harmless if it leaks. In spite of the stories you hear - there are no known examples of compressor-powered household refrigerators using ammonia. Several of us here are fascinated with the early days of refrigeration and are constantly on the search for a new model or new things we haven't seen before. Nobody has found documentation that an ammonia compression fridge was ever marketed. Don't get me wrong - none of us have seen it all! I would love to be wrong and love to have one in my collection.  

The incident with the door staying open overnight may or may not have played a factor. In and of its self, it would not have damaged the unit.  However it would have placed a much heavier heat load on the unit. This is because the door normally excludes warm air from the room. With the door open this allowed heat into the cabinet at a higher rate than it would have received otherwise.  If the unit was completely healthy, that would not have been a problem. If the condenser fan had gradually stopped working weeks or months before this, there is a chance the unit could have stayed frosted and managed to function without it. This could happen as long as the evaporator stayed covered in frost and the door was closed. The limited amount of heat going into the system could have been radiated naturally, without the fan.  However with the fan stopped, and the door open, this could have placed more heat into the system than it was capable of rejecting. 

That sort of operation should have tripped the compressor overload breaker, stopping the unit before damage was done.

To help get to the bottom of this, you'll need to take the cover off the cooling unit. Verify that the fan and the compressor are both running. Verify the condenser isn't clogged with dust. 

If the compressor and fan runs but there is no cooling, it is very likely that there is a leak somewhere. This is doubtful as well, since there is really no way the door being open could cause a leak to develop.

Please let us know what you find as far as the fan and compressor working!
Sincerely,
David

Hello, thank you for the reply! It's a relief that it isn't a toxic refrigerant! It is probably just coincidence that everything happened around the same time. Door left unlatched, defrosting and it not cooling. But it's always worth mentioning just in case. The fan and compressor are both running. We blow out the dust frequently and always oil every couple months. It doesn't sound like the compressor is ever under load if that makes sense? We have located a company that is supposed to come out tomorrow and see what they can figure out. Fingers crossed here that they can solve the issues. I will be back with updates tomorrow. And possibly more questions on how and what we will need to repair.

Thank you all so much for your time and replies. I'm ready for the Old Fridge to work again.

It is not ammonia.

Hello and welcome to the forum!

What you have is an fea  it’s a replacement for a monitor top fridge. 
Monitor tops were not made after ww2 ,  but since there were so many out there still being used after ww2  ,   and  still in use they came up with a replacement for the compressor that 
sets on top of the cabinet.   (FEA) They are very reliable fridges and work well , keeping the fan oiled is one problem that they seem to have. 

It's a good point about him not causing additional damage. 

One issue with these is the ports on them. It seems that some of the FEA's have ports which work with the same valve kit used with the original Monitor Top service ports. Some of them seem to have a proprietary non-threaded port; which I am assuming requires a GE specialty adapter. Either way, there are no "conventional" service ports on the unit; therefore one or two will have to be added - unless you are planning to locate the original tools.

Since nobody knows for sure if there is any refrigerant remaining in the system, it would be wise to install a piercing valve (at least temporarily) to see what is happening with the system. The piercing valve clamps onto a section of line and pricks a pinhole in the line to gain access to system pressure. Once you have a low-side service port in place via the piercing valve, it will be possible to properly troubleshoot it.

So now you can connect gauges to see if there is pressure in the system. If the pressure is low; say in the 20 or 30 PSI range; there could be enough gas left to allow an electronic leak detector to be used. If the pressure is zero, then I would place nitrogen in the system; up to the test pressure for the low side. With that pressure, you can apply soap water to the system and look for leaks visually. Pay close attention to the evaporator where the lines attach. 

If the pressure was still high (80PSI or so) you would want to run the compressor and see what happens to the low side pressure. That info would guide the troubleshooting from there.

Hope this gives you some idea of what would need to be done to move forward with this.

One word of caution. People have been saying that going back and forth between automotive and hermetic compressor systems, with any one gauge set is a bad idea. The reason is that most R134A automotive compressors require PAG oil which can prove harmful to the winding insulation in electric compressors. They say that this PAG oil, even in tiny quantities, can lead to failure. Due to that, hoses which have been used on an automotive R134A system should never be used on an electric hermetic compressor. The reason I say "they say" so many times above is because I haven't ever taken this risk; so I can't say for sure if it would be an issue or not. I have seen leaked PAG oil on a car A/C strip paint from the engine; so the oil does have the ability to attack some coatings it seems.

Sincerely,
David