CC Bus air condition problem

[truk4u]

Roger,

CCI is not Country Coach International. CCI/York is the compressor mfg.
http://www.tccimfg.com/

[Liam]

Thanks a lot for the info. I will put that on the list to fix. Lots quieter than roof air. The freeze up could well be dirt. There are no filters on the units and the galley floor is dust-bunny city!

[johnklopp]

The York compressor is a 2 cylinder reciprocating design from the late 1950s. It has a crank shaft similar to a small engine and has a relatively high vibration level and a tendency to brake mounts, however it works well and is easy to replace.

I would strongly recommend replacing any York compressor with a Sandon compressor.

The Sandon compressors are available in 2 types. The reciprocating version is typically 6 cylinders arranged like a rotary aircraft engine. Rather than having a crank shaft it has a wobble plate on the shaft that causes the pistons to stroke parallel to the shaft itself. The smaller displacement of the multiple pistons causes a significant reduction in vibration.

The best choice in my opinion is the Sandon Scroll TRSA12 with 121.1 CC of displacement per revolution. This compressor is smooth, quiet, dependable and cheap. The maximum sustained speed is 10,000 RPM, around twice the rating for the York. The scroll compressors are great due to the ability to ingest limited amounts a returning refrigerant liquid that would instantly destroy the York recip since liquids don’t compress well.

The compressor selection is not difficult but requires a little analysis to ensure the correct application. You cannot go to the auto parts store and buy the correct version of the compressor unless you know the car that it was originally installed on.

The rotational speed is selected to match the required cooling capacity. The speed is adjusted by simply changing the diameter of the compressor pulley. Different pulley belt types are available to match the drive pulley belt type on the bus. Several suction and discharge ports are available and need to be selected to match the hose end connections. Several hot rod air conditioning suppliers offer a Sandon adapter to retrofit 60s cars with the Sandon compressor.

The best compressor source is Omega in Texas since they can take the base compressor and add port plates, clutch diameter and belt types to give you an erector set approach to your application.

Have Fun.

[Liam]

Awesome data, thanks. Our new geothermal uses a scroll which are supposed to be great. The ability to injest some liquid should help with surviving the freeze-up issue someone mentioned as i think a dirty exchanger can return fluid. Where do folks find most of the leaks? Wondering, given how inaccessable some of the connections are, burried say under cabinets.

[mike kerley]

Liam, I'm "pretty sure" most of my leakage is through the walls of the hoses connecting the system. Your correct, getting to some of these connections is a real challange. Just cleaniong coils and fan motor blades is tough to do. All part of the fun!

[johnklopp]

I would be very skeptical regarding the hoses leaking due to hi permeability. It’s true that the hoses are different for some refrigerants, but the leak rate will be low even on something as large as the bus.

You’re most likely locations for an open compressor split system leak are the compressor shaft seal followed by any screwed or clamped connection. Note the o rings used on some connections are much more likely to leak than the hoses themselves.

If you can’t find the leak isolate the individual components then run a standing pressure test followed by a standing vacuum test. Some leaks will appear under vacuum rather than pressure. Add dye to the system and find small leaks with an ultraviolet light.

[rahangman]

John, thanks for the advice. We will attempt to isolate any/all components to vacuum/pressure check before we fire it up. I have my thoughts about the receiver/filter and we will of course install a new one. The one that is being replaced has a number on it that no supplier has been able to find to offer a sub. It is located on drivers side of engine bay close to rear door and is metal strapped against the frame. The provider of my compressor is hesitant to tell me a particular unit, but suggests it must be one of sufficient capacity and to subscribe to a knowledgeable Tech suggestion.

[dreamchasers]

Roger,

I purchased my dryer replacement for the Prevost "dash air" from Prevost, Fort Worth. If you order before 2:30 pm, they can overnight it to you. UPS overnight works good in east Texas.

Good Luck

Hector

[mike kerley]

"I would be very skeptical regarding the hoses leaking due to hi permeability". According to Prevost service, if you dont change the hoses plan, on adding 12-24 oz of R134 per year. So far, they've been dead on. If you have a major leak, you'll see the oil or add some dye and watch for the color...

[rahangman]

This bus was converted to 134a before I bought it. The hoses are not anywhere "New" but the pull down and servicing did not identify any leakage. How would I determine approximate age of existing hoses, in the engine compartment of course they don't look "bad" but not anywhere GOOD. There is a lot of corrosion on the hose fittings and I can imagine what it would be like to start trying to break them loose to replace, especially with no indication of leakage. I know there is an age date on the hoses life not unlike our tires, just wondering. Talking with Foretravel here today and local Napa , I will take current receiver/dryer into their shops for a look see. I don't want to put exact same dryer in , in case it was the cause of the compressor failure. Both locations mentioned that the quantity of the desicant was the critical concern.