Frigidaire W-8 Belt Drive Fridge Repairs...

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This fridge belongs to the owner of a historical home, who wanted it returned to working condition.

It's a two-door porcelain cabinet W-8 model. It has what appears to be the original condensing unit, with the original repulsion-induction motor still in place. The fridge is complete, except for the cover around the evaporator. We are still searching for a cover.

The system was a SO2 system. Over decades of disuse, the system had suffered some deterioration and ill-fated repair attempts.

The compressor had apparently become frozen up, and someone had used a hammer on the flywheel to try to rotate it. That had apparently given them a face full of SO2 because the shaft seal was completely gone after that attempt.

The motor would run, but it was not sounding good. The front bearing had become worn severely. Thank goodness I had a spare end cover for a Delco motor and was able to replace the worn bearing.

The compressor had no compression because it was so clogged with carbon debris. This is the nature of SO2 systems. They are all so many decades old, and the SO2 is reactive and corrosive when water gets in. They are always in bad shape.

I wish our forum had a way to put captions on the pictures. It may have that but I don't know how to use it.

Most of the pictures are self-explanatory. The evaporator was opened up and cleaned out. It was full of old sludge and oil. That oil smells like the old days. Makes me think of gun oil and an old gas station. I love that smell.

The float got a spring to adjust for the lighter density of modern refrigerants, the needle valve was machined to remove the wear and grooving; and the mangled lead gasket was replaced with Teflon.

For the electrical parts, the fuseholder had what appeared to be Gorilla Glue holding one of the wires on. That would definitely not work. Had to take that all apart and refurbish it.

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The evaporator was filled with full-strength Zep Purple Degreaser. It was then agitated and forced to flow through the tubes. After that was poured out, a side-shooter pressure washer tip was used to blast directly through the tubes. That got a lot more sludge and crud out.

Once that cleaning was done, the next thing was to place the float in the header and pull vacuum on it to remove any residual water.

The motor was full of grime and oil and grunge. That needed cleaning with brake parts cleaner. Once it was clean, a new coating of insulating varnish went on. Notice the gaps in the motor winding? There is no start winding, only a run winding. That makes it look odd. The motor starts by repulsion-induction mechanism which is all internal to the rotor.

I don't understand how "half a screw head" was broken off the fan pulley screws. That made it sort of difficult to remove them, to say the least!

The compressor was in a sad state. It was so frozen up that I had to fashion a puller, to press the pistons out. Once that was done, everything was able to be cleaned up.

The shaft seal was completely buggered up into a ball of crud. I think it was a replacement seal which had been installed after the unit had been run for a few decades. There were rubber parts in the seal which I have never seen before.

I replaced it with a new elastomer seal; after machining the shaft.

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The compressor was cleaned up with more Zep purple degreaser. All the decades of sludge are gone now!

The new seal bushing was made and installed.

It's amazing how precisely the parts of these compressors fit together. The pistons don't have rings and yet they wuill pump 180 PSI without bypassing, due to only an oil film sealing the piston-to-bore clearance.

The cylinder-to-base interface was sealed with a liquid rubber material called Permatex Right Stuff. It is strong and fully resistant to alkylbenzene oil and hydrofluorocarbon refrigerants. The head gaskets are made from a fiber gasket material specifically built for semi-hermetic compressors. It's compatible with almost all refrigerants and oils.

The last picture, of the wood cabinet work; is showing the insulation. The first Frigidaire I repaired had some aluminum foil and air-space insulation which was deteriorated badly. This one has a hefty layer of mineral wool insulation. No need to replace that.

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Going back together with it!

The original filter was just a screen and not a dryer. I replaced it with a soldered-in liquid line dryer. That's visible above and to the left of the compressor.

It held vacuum for 3 days or so; which is a good sign.

Before installing the condensing unit, I noticed the spring hangers were almost completely worn through. That is 80 years of use showing up.

I built new ones to ensure no incidents happened.

Charging the unit was an adventure! It seemed never to be full. In the end, it took 100 ounces of refrigerant!

The cabinet also received a light install. The light is on the inside of the center post. It's a flat LED module. The wiring follows the refrigerant lines and the light fixture is attached with two-side adhesive. No holes were drilled.

The light is controlled by magnetic reed switches. These are under the lower breaker strips, in hollowed-out pockets in the wood. No visible modifications to the breaker strips. The magnets are attached to the bottom edge of the door, also in the wood.

When both doors are closed and both magnets are engaged, a relay turns off the light. The relay and miniature 12V power supply are hidden in the upper left corner of the compressor compartment. I placed them behind a wooden cover which should blend in with the original construction.

 

The motor originally had no overload protector, depending instead on a 6 amp time-delay fuse. This fuse had been bypassed in decades gone by. I reinstated the fuseholder into the circuit. Into it, a 15A fuse was installed. To protect the motor, an external automatic-reset thermal overload protector was installed. It's concealed under the unit inside the junction box where the power cord is attached. 

 

Between the compressor and motor, there's a sight glass. It allows you to see the liquid refrigerant flowing past, leaving the reciever and passing to the float valve. This should always be full of liquid and not have bubbles passing. It's how you tell when the system charge is adequate, since we don't have a factory charge amount to reference after leaving the SO2.

Here is the first of the videos about this fridge. I am doing multiple projects at once and my time is pretty short, so the videos may not be as thorough as some of my previous ones, but you can still hear it run!


Sincerely,
David

 

[goatfarmer]

nice job!

 

[Ultramatic]

 

 

Mighty impressive as always!

 

[repairguy]

That’s great! Your talent is amazing!

 

[turbokinetic]

Thank you!

... for the positive comments! I appreciate it. 

 

It seems there are scarcely few of these left running in original condition. Most have been relegated to storage cabinets; with the compressor unit lost to the scrap pile, decades ago.

 

Every now and then you see one restored in use, but sadly, they have a non-original cooling system.

 

The few which are left, complete, should be preserved. We need to remember the early days and having a working machine to see and hear is a great way to keep those memories alive.

 

 

 

 

 

[repairguy]

Agreed! I like to remember appliances that ran for years without a single service call in many cases. And when your appliances broke you had them repaired instead of sending them to the curb immediately and purchasing a new one . Not much choice these days with planned obsolescence built in to most. Keep up the amazing work!

 

[rp2813]

I couldn't agree more with the statements above, including your own, David!

 

Every time I see that you've disassembled something down to such tiny parts as float needles and are able to keep track of everything to put it back together, I am truly amazed and impressed.  It's also reassuring that the owner of this box sought it out in order to have it restored and placed in a period kitchen.  That's almost unheard of anymore.  If more people took this approach, it would knock HGTV and its scorched earth tendencies off the air.

 

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Tiny parts....

Hi Ralph!  I have been trained to keep track of tiny little parts because of the type of work I do for a living. Older diesel engine governors had a level of tiny parts which would make this look like tinkertoys! 

 

It's not "trivial" but it is possibly through careful attention to detail, and keeping parts organized in ziploc bags and segmented trays such as fishing lure boxes. 

 

 

 

[48bencix]

I had no idea

I did not know that these older units could be converted to a modern refrigerant. Very nicely done project and really great pictures and explanations of what you did. This Frigidaire may actually be pretty efficient, thick doors and walls.

 

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Technical Details....

@reply 11

Martin, it's just a matter of adjusting the parts of the unit for the properties of the refrigerant in use. There is a lot of hype and "black magic talk" about which refrigerants can work in which units. It's not magic at all. It's a matter of selecting an appropriate combination of refrigerant and oil; then making adjustments to the unit so that it will do its job with the new refrigerant.

 

Thankfully Frigidaire was very popular when new, and the service literature is available. By studying how it's supposed to work with SO2, it was possible to discern how to make it work with modern materials, with the least modification.

 

These units operate on the same vapor compression cycle that all compressor-based systems use. Sulphur dioxide is one of the most aggressive and damaging refrigerants which was used in household refrigerators. Anything resisting SO2 should have no problem with modern refrigerants.

 

Shifting away from SO2 gives a lot more flexibility to recreate gaskets and seals using modern materials. This makes for a much easier repair process and allows for adapting readily available components such as a shaft seal from a car A/C compressor.

 

The biggest difference in this system and modern ones is the metering device. Whereas modern systems use a capillary tube, or a thermostatic expansion valve; this machine uses a low-side float valve.  For a low-temp system to work efficiently and effectively, it's important for the compressor to recieve only vapor (and oil) returning to the inlet. In modern systems, this is accomplished by a carefully chosen charge amount of refrigerant (with cap tube systems) or with a specifically adjusted superheat level for TXV systems.

 

With the low-side float, the evaporator is filled up with liquid refrigerant. The heat load from the fridge cabinet boils off some of this refrigerant, which rises to the top as a vapor. The compressor's suction line originates from the top of the evaporator header, where the vapor will collect. As the  liquid refrigerant level goes down, a float mechanism will open a needle valve. This will meter in a small amount of liquid refrigerant to replenish the level of liquid in the flooded evaporator system.

 

So, basically, it maintains a constant level of liquid in the evaporator, admitting liquid gradually from the high side, to replenish only what boiled off.

 

The return of oil to the compressor, is another interesting aspect of these. Originally, it used SO2 and mineral oil.  Turns out that small amounts of mineral oil will mix, when warm, with the liquid SO2. The compressor is an oil-sealed design. It pumps a lot of oil out with the hot gas refrigerant. The refrigerant condenses and mixes with the oil, in the receiver. When the liquid SO2/oil mix passes from the high side to the cold side, in the evaporator, the low temp liquid SO2 and oil are no longer miscible. The oil floats to the top and forms a layer, because the density is a lot less than SO2. When the refrigerant boils, the rising gas causes the oil to froth up and reach the compressor's suction line, thereby getting returned to the compressor without carrying liquid refrigerant with it.

 

When choosing a modern refrigerant, I wanted the miscibility to be as close as possible to the properties of SO2 and mineral oil. In doing some research, it turns out that alkylbenzene oil has a certain level of miscibility in R152A liquid, when at warm temperatures only. So, that was the combination chosen. 

 

The temperature / pressure curve for R152A operates at a somewhat higher pressure, but not as severe as some other alternative refrigerants. Because of this, the control springs required adjustment, as shown on the video. 

 

This one is my third low-side float / belt drive Frigidaire repair. The first of them has been running over a year now without oil circulation issues or any other chronic problems.  The second one has been going almost a year. I would expect that if there was a compatibility or functionality issue it would have made its self known by now. 

 

This two-door fridge seems to operate at about a 30 to 40% duty-cycle. That's in a very warm workshop in summer in Alabama. That's a pretty nice and low run time. It might not be too inefficient. And you'ere right about the cabinet insulation. I unplugged it for a few hours to move some things around in the shop. It had just started defrosting when I opened it up. The water bottles were still ice cold.

 

Hope this is interesting info for y'all! 

 

[swestoyz]

Without words...

David - amazing, amazing restoration, but a very insightful and easy to follow explanation of everything you did, and the 'why' behind it all. Thank you for sharing this with us!

Ben

 

[sfh074]

I think it is way .....

cool but *funny* at the same time ..... that the go to choice for an alternative refrigerant is R152A. It is a great replacement for anything using R12 and has been used as a replacement for R134A systems as well with great results.

I wonder how many vintage refrigerators have been scraped over the years where people thought they had to use R12 exclusively in older vintage refrigerators that had lost its charge or dead compressor, etc .... and no longer could get R12 or unwilling to pay for it since it is now worth its weight in gold. Same thought with refrigerators that originally used SO2 like the one David is working on.

R152A is very close in properties to R12. But the funny part is that it is the main ingredient in those pressurized duster cans that you can buy at Office Depot or Walmart for that matter. A big 14 oz can costs all of a few bucks and basically can replace R12, R134 and SO2. In R12 and R134A systems, very little to no modifications required to make it work. As in David's case in this SO2 system, he had to change the spring tension on the float.

David has a couple of older but great videos where he substitutes R152A in his automobile's R134A system and a vintage refrigerator that originally took R12. He goes thru the steps and shows the tool (can tap) that you use to harvest the R152A from a common duster can. Highly recommend these videos!

Bud - Atlanta

[this post was last edited: 8/26/2019-18:24]

 

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Thanks again for the kind words. Ben, very happy it made sense to you how I explained it.

 

Bud, yes I have done quite a lot of alternative refrigerant experimentation. 

 

I do not want to go into environmental politics, but I have to slightly touch on it, to explain the reason for my experimentation.  Regardless of what you believe is true (or not) about the effect of refrigerants on the environment; the powers that be have established a (roughly) 25 year cycle of inventing, then banning different refrigerants. Each time this occurs, it forces people to spend great amounts of money on new equipment and materials. The CFC refrigerants were replaced with HFC, which are now being phased out for HFO. They currently say "no known environmental issues" with HFO refrigerants; however I would be willing to wager that in about 20 years, they will have discovered some reason to ban them and invent a new and more expensive alternative.

 

It's important to the hobbyists and those who want to preserve the old technology to have "known working substitutes" in waiting. At this time, there are enough machines out there to risk experimentation. In another 20 years, there could be so few that nobody dares risk something unknown. By making tests now, we will have proven-safe paths forward for many of the cooling systems.

 

To that end, I will be experimenting with some HFO refrigerants before long. The info on oil miscibility is the most worrisome aspect. I'm not sure if there will be a suitable oil combination for these in low-side float systems.  Time will tell. We should have quite a few more years of HFC availability yet, during which to come up with another oil choice for the HFO gases. Currently HFO are very expensive and hard to obtain. For that reason, I won't be able to do extensive testing for the time being.

 

Sincerely,

David 

 

 

 

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Check this out...

Here is a bit of ephemera related to our hobby. This booklet was inside the refrigerator. 

A PDF copy with all pages can be downloaded here: 

[COLOR=#385898; font-family: Helvetica, Arial, sans-serif]<span style="font-size: 14px; font-weight: 400;"><span style="text-decoration: underline;">http://home.hiwaay.net/~davida1/IMG/Frigidaire_A_General_Motors_Value.pdf[/COLOR]</span></span>

 

[sfh074]

Wow ....

$332 for the W-8 back in 1932?! I am assuming that year since the document that came with the refrigerator is dated 3-32 An inflation calculator says that is $6400 in today's dollars. Dang

 

[circlew]

Interesting booklet from Frigidaire. I'd never heard of the Moraine budget priced models before. Evidently they chose this name due to one of their plants being located there (south Dayton suburb).

The console air conditioners are interesting. I remember seeing one of these in a doctor's office I went to in the 70's. It was in an old house that hadn't had much done to it since the 30's. The unit was still functional. I imagine these were pretty expensive at the time.

The compressor shown on the last page reminds me of one that was in my dad's uncle's grocery store. It was for the Frigidaire freezer case where ice cream was kept. They also had Fairbanks-Morse, Friedrich and Copeland units. That motor room was very noisy, and I thought it was scary when I was a little kid.