So, this top assembly from a 19323 General Electric CA Monitor Top fridge came from the scrap yard. It was seized and had all its useful parts stripped.

The General Electric CA model was used only in 1933 and 1934. They used a very low pressure refrigerant which was only ever used in these two years of Monitor Top. This Methyl Formate refrigerant will degrade with time and heat, releasing non-condensable gases into the system. This requires maintenance  bleeding of the system.

The low pressure characteristic of this refrigerant meant that the compressor had a large displacement. The large size of the moving parts, compared to the small motor power means these will become "stalled," "stuck," or "seized up" very easily. This often happens from sitting, lack of bleeding non condensable gases, or from loss of the crankcase oil heater.

This is a hermetic motor compressor with the unit welded into a steel casing. The only access to the compressor is vie electrical connections to the motor's terminals.

In this video, I try increasingly forceful attempts to re-start the seized compressor.

Thanks so much for the positive feedback on my projects here. Makes it easier to justify spending the time to participate!

twindubdexter; LOL I was never very good at school.... I was always daydreaming about tinkering with motors and mower engines and old junk to play with after school! I've always had a fascination with technical things and when I was a kid, air conditioning and refrigeration was a sort of "black magic" that very few understood and even fewer could work with. That's one of the reasons I was drawn to it.

So, I continued tinkering with the CA this morning and I believe I found the root cause of the seizure of the compressor.

The system had its service port soldered shut; which would preclude releasing the noncondensable gases from the system. It had massive pressure built up in it. A second possible contributing factor would be the lack of a crankcase oil heater. That was burned out. These heaters often fail while in storage, so I can't say for sure that was failed at the time the unit stopped working.

Here is some video from this testing:

The meter readings are power of 161 watts; down from 400 or more when I stopped it last night. The other is motor current which is also way down from where it was.

The port with the clear hose and oil is the bubbles of NCG coming out. It took half an hour or so to bleed off!

Hi Jon! 

The CK Monitor Top has condenser tubing in the round "drum" on top, and in the top deck surface of the cooling unit (the flat part that covers the top of the cabinet.) These tubes will get hot within seconds of turning on the compressor, if the system is healthy. When the unit has first been turned on, after the whole thing is at room temperature, the condenser tubes will get really warm, almost too hot to touch actually. Once the unit has cooled down and started cycling off and on, the heat will be much less.

However, I believe he probably has a CG Globe Top since you say the "top and sides" get hot.  The CG Globe Top has the condenser tubes in the actual "side surfaces" of the cabinet top, as well as the top deck area.  There is an area of what looks like "decorative ridges" around the top of the CG cabinet which are the condenser tubes. There is less surface area to dissipate the heat with this design (compared to the CK with drum-style condenser) so these seem to get hotter. I don't own a CG and I'm going on what others have said on that - just letting you know.  :-)

To know if this is actually a problem, we would need to know the motor power demand; how cold the evaporator gets, and if it is able to cool down and cycle off. My CK condenser gets almost too hot to touch after an ambient temperature startup; but once it runs a while it's not that hot. If he's getting scared of it and turning it off prematurely, it may be that it's not getting time to stabilize.

Toploader55; Thanks for the comment!  Yeah, it still appears to have a charge in it, at the proper level. The refrigerant is methyl formate which is extremely frustrating to obtain. It is not a controlled substance, and not even a licensed refrigerant. The problem is there is only one supplier in the country. No matter which distributor sells it to you, it comes from the same suppler. They refuse to ship it to anything other than a registered commercial address. I have as of yet been unable to successfully receive a shipment of it.

I love the Monitor Tops. The best one is the 1935 or newer CK type. These have a Scotch-Yoke compressor and come from the factory with sulphur dioxide. These will work with most modern refrigerants without any modifications, and they usually are still functional. That's the one to go with if you are just starting out with the antique fridges. :) 

Hi, robbinsandmyers; thankfully only the CA methyl formate machines produce noncondensable gases. The other refrigerants do not break down chemically in the way MF does.

However; SO2 (sulphur dioxide) does have its own set of major drawbacks. It runs in a vacuum on the low pressure side of the system. It becomes violently corrosive in the presence of water. Therefore if there are any leaks, no matter how miniscule, the system will draw in air and moisture while running. The air will result in noncondensable gases; and the moisture will result in corrosion.

I'm not trying to say it's all doom and gloom. Just be vigilant for any signs of trouble and address them ASAP.  Another very good aspect of the CK machines is that they are not "married to" the SO2 refrigerant and there are modern, noncorrosive, non-irritant, inexpensive refrigerants which work in them, without any modifications. So; if a leak happens, you correct it, recharge, and keep going in better shape than before.

I would love to get a Grunow to fix up. Thankfully methylene chloride is not hard to get like MF is. It is, however, very aggressive and would require special materials to re-seal the compressor.

I believe early Carrier A/C also used methylene chloride, under the brand name "Carrene."

Hi Eronie. I agree, these are fascinating. I love the technologies that were tried, marketed, and walked away from before things were "standardized" as they were.

Hi Norgeway. It's confusing because there is "Methyl Chloride" and "Methylene Chloride" which have both been used as refrigerants in the past.

Methylene Chloride boils at 103 degrees F and works in a vacuum as a refrigerant. This was sold as "Carrene" and used by Grunnow.

Methyl Chloride boils at -11 degrees F and works similar to conventional Freon refrigerants. This is what they are theorizing had been substituted for Freon in the Cocoanut Grove tragedy.

en.wikipedia.org/wiki/Cocoanut_G...

So, here's an update on this one.

Got her rewired, new crankcase heater installed, and made a new coil for the start-relay.

The original wiring was really horrible!

Thanks, I'm very pleased that you guys are enjoying my old fridge repairs!

Hi Stan, yes it's upside down for the rewire. The painted drum part is the top. It's not easy even with it upside down LOL!

Hi Stan. It's not that hard to do; and furthermore with the CK you have a lot less to lose from a refrigerant standpoint. If you break a line, you can fix it and re-charge with a minimum of cost.

Hi Eddie. Thank you for the kind words. I really appreciate this.

I understand what you mean by "the sound of quality." It's a smoothness, non-stressed sound. You can tell the machine isn't running its self to death.

I do love teaching others and showing off these machines. One of my main problems is social anxiety. When I'm by myself or with one or two close friends, it's OK. But with a group of unfamiliar people I am very uncomfortable.

Stan, yes I agree with Lorain that it is good to replace the wiring whenever possible. The situation with the GE Monitor Top refrigerator is a tough one. You always run the risk of breaking a line and causing a refrigerant leak when moving the parts around to access the wiring.

The flip side is, it can severely damage the motor if the wiring faults. Some CK units have dual thermal protectors, one in the temperature control, and another in the start relay. Others don't have the safety device in the start relay and only have the one in the control. If there is a wiring fault; particularly a ground fault; it can effectively bypass the overload relay.

Therefore, it's a good idea to replace the wiring if you see any signs of deterioration when doing repairs. In other words, if nothing's getting disturbed don't disturb it just to change the wiring. But, if the start relay or the control need service, I would not try to re-terminate the original, crispy wiring back after the part is serviced. If anything has to be done, change all the wiring and go back with new.

Being that this is a sulphur dioxide system, I would take the unit out in an area where it can safely be walked away from if the unthinkable happens. If that were to happen, it is fixable so don't think you have to give up. Just watch out for your safety when working on the system.

That's my personal way of dealing with these, and ensuring they are safe for the user and the machine its self.

LOL at worrying about being flamed!  I also liked the way it looked in bare steel! I was tempted to buff the whole thing and clearcoat it! 

But, I went back with gloss white to match the porcelain cabinet. Check out the pictures of the completed paint job... I think it looks pretty nice!

Thanks so much, guys. I really appreciate the compliments.

In reality; it's a great 10 food paintjob. The color does match very well. It was a learning experience for me with the epoxy paint. It sprays very watery and takes more time to gel up than the paint I normally use. I tried to warm up the area and the unit by hanging the heater on the hoist and having it blow on the top of the refrigerator. It seems to have only warmed up one side of the condenser, so when I painted around to the other side, the paint didn't set up, and ran off instead. Again - it's not horrible but... I'm glad it wasn't someone else's item I was painting. I would have to redo it if so. But for what it is, considering the condition of the rest of it, it's passable! 

This cabinet I recieved with a completely burned motor CA-2-B16 top on it originally. Some of you guys may be following the teardown videos of that unit. As you may have seen, that top was completely clean and showed no signs of ever having had been exposed to rain or moisture. The cabinet insulation also appears to be in similarly pristine shape.  For it to be "show quality" the door would need to be replaced because of the deep scratches. They look like someone pulled a highly tensioned steel wire rope across the door. If it weren't for that, the cabinet would be an 8/10 with no repairs other than cleaning.

As for the racks, I have many which are ugly. The setup and cleaning is the worst part, so I may just gather together all the bad racks and try to nickel plate them. This is not hard, from what I've read. It's especially easy on things that aren't smooth and polished. In that case, the nickel provides a rust resistant coating but there's no need for extensive grinding down and polishing before hand. If I do attempt it, there will be some videos and documentation. :)

So, to run-down what I have done to this:

Make assessment of the compressor, and get it running again.

Bleed noncondensable gases from system.

Rewire the top, completely, adding a modern, auto-reset thermal overload breaker in the circuit. Now it has two; original in the control plus the Klixon type.

Built a 3-wire grounded power cord. (Note, still have to install a cabinet light plug in this cord.)

Located a replacement start relay since the one was missing. Had to replace the coil.

Wipe down cabinet inside and out with Rain-X and Scotch-Brite pad, to clean the porcelain.

Stripped, primed, and painted the top.

Blasted, painted, and clearcoated the control faceplate.

Installed adhesive rubber door weatherstripping.

Some of my YouTube viewers aren't on our forum here. It was raining (loudly) on the metal building yesterday so I couldn't video it.  Also, heater had been off, so I couldn't run it. Today I plan to make a video of the completed repair as well; so there won't be folks who feel as if I stopped short of a complete project LOL!

I really am amazed at the amount of engagement everybody has with these projects. It's satisfying to me, making something that looks and functions well. It's also great when I see others following along and learning and enjoying it as well.

Nothing I did was really hard, nor did it take any special physical skills... just motivation and patience. The paint stripping was the worst part for patience.

Well, you know..... I don't think I'm selling myself short. Nothing was hard to do; but it does take a lot of experience and knowledge to know what non-hard steps to take. I used Google and the Monitor Top club forum as guidance. Also when you are happy doing something it makes it seem a lot easier!