CC Bus air condition problem

[rahangman]

I need to find a Sanden Compressor TM31HD with Part# 0630-9620 Ser#9694789076 and will try Red Dot and Omega which I found via a Google search, on Monay....any help?> My "Oldie" does not have a Prevost Tecumseh unit at all, so I am looking for this one to provide for me and my gal while driving. Been using Cruise airs but am willing to give it a try now that I have someone knowledgeable to work on it. Thanks ;)

[charlesebrownjr]

Is this the CC Over The Road A/C. I have a 99 CC and this is the compressor I have been using. This is who makes the compressor or imports it, http://www.valeocompressors.com/
You can get them at discountacparts.com. There part #60-02464 NC. (They are only $1095.00) with 12 month warranty! Good luck.

[rahangman]

Thanx, I will give them a call Monday AM. Am in Nacogdoches now working on it. Hope to get one sent pronto so I can go home. Maybe I ought to to via Monroe?

[dreamchasers]

Roger,

If you are running R12 freon, as I am, you will need to drain the oil (PAG) from the compressor and refill with mineral oil for R12 refrigeration service. That is the method I used and have been running a replacement compressor for three years with good service. I ordered my R12 from Ebay ($450 for 30#). Be sure to perform a through leak check to insure longevity.

Just a reminder.

Good Luck,
Hector

[rahangman]

Thanx for the heads up, Hector, but mine has been changed to 134a previously. Trying to figure out for sure if CC did the AC or if one of the PO did the job as there doesn't seem to be any evidence of ever having a Prevost Bus Air compressor (Tecumseh) in this one.

[Liam]

I was told by a prior owner to not even try to keep the chassis A/C working, that it is a hopeless cause - run the roof air. Curious if there is strong opposing experience from CC owners?

[mike kerley]

Liam, Our 93 dash air (with galley and bedroom units attached) was converted to 134 by the previous owner. Same hoses as R12 used. If I recall correctly, Prevost wanted "about" $4,000 to change out the hoses for 134. We have some leakage, amounting to giving the unit a charge twice a year. Normally about 12 oz. Dash air works fine and my only complaint is the fogged up windows at night from the cold air hitting them. I've been through two clutches and one compressor (technician broke the compressor pulling the clutch off) in 7 years.

Its important to keep all fans on high speed on our bus or the units freeze up, even when properly charged. Maybe dirt on the coils, but they look fine.

[truk4u]

Liam,

I think the previous owner was full of it when he told you to not even think about keeping the dash air going. I'm on my 4th bus with dash air and yes the compressor's may only last a couple years, but they're 239.00 each, so in the grand scheme of things that's chump change. The key is making them leak free by using using high pressure nitrogen, vacuuming and changing the dryer. When working properly, the CCI/York Compressor does a good job considering the amount of space your trying to cool. I see today there was a new ER210L-25149 on e-bay for 189.00.

[dreamchasers]

I agree with Tom.

I have reworked both of my ACs on my 1995 CC and they have worked great. It is important to get your AC system leak free for reliability. With the high temperatures in Texas this past summer, my dash and salon AC worked to keep the coach cool. Only when the temperatures were 100 plus did I turn on the roof airs. The dash air blowing cool air on me works for me.

Hector

[rahangman]

Truk, you mention CCI (Country Coach Inter) with York compressor (?) I have a Seldan and having found one that I was going to order tomarrow, would love to save some $$$ . What can you tell me about the YORK?

[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.

[BenC]

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.

Country Coach used barrier hose that is compatible with 134a, but Prevost, for the dash a/c system, DID NOT until they switched over at the last minute when the government mandated it. If the system was converted, were the Prevost hoses to the dash a/c replaced with barrier hose? If this was not done, the system will continually be a leak problem from the Prevost hoses.

[truk4u]

Ben is dead on as usual, Prevost dash air on my previous 94 Liberty was Non Barrier hose and not compatible with 134a. Further, Prevost told me the dash air hard pipe freon lines did not go all the way from rear to front and had hose sections midway, necessitating a major expense when converting to 134a. You can buy a lot of R-12 for what the conversion costs.

[rahangman]

Current Update and I apologize for being a bit "tardy". We have replaced the Compressor and receiver/dryer in the engine compartment. As I mentioned before, I do not have the Prevost Bus air, only the CC system which seems to have been piggy backed on the original Prevost Bus air. Now, servicing and starting up compressor provides excellent cold air to bedroom and galley condensers & cabin, however , the dash air is not doing as well. The solenoid behind the front bumper is suspect. I have closed my valves on the engine to the front of the bus, but, still not much hope. Drove the bus a short distance and while driving, I thought I felt some increased cooling from the dash ducting, but not holding out for the solenoid change out. When I take "Her" home this week end, will see if extended driving might free up the solenoid. Will report back if anything changes, if not will be looking to replace that solenoid. Pray for me, (hee hee).

[Jon Wehrenberg]

Rodger, If you can easily access the solenoid valve check the coil for open windings. If the coil checks out and you supply power to the coil you are likely to actually hear or feel it click open. If you do hear it function check elsewhere rather than having to evacuate and recharge the system again. It might be as simple as it is not getting power.

The Prevost web site will have the diagrams for your coach's electrical system which should be a good starting point unless CC modified it.

http://prevostparts.volvo.com/technicalpublications/en/wiring.asp

[mike kerley]

Roger, Just a heads up. My dash AC also seemed to be on the fritz last summer, while the other two evaporators worked fine off of the same compressor. Found my temperature knob (heater control knob) was turned up, causing warm air up front. Most likely bumped it with my leg at some time getting in or out of my seat. I'd look at that...My dash cooling also only works when bedroom and galley units are turned on, which is good because they will ice up if the fans are not running on high speed. So, when I run dash air, all units come on at full speed except the dash and I can get by at 50% speed on it without icing up..

FWIW: