OTR AC - My Bad

[Jerry Winchester]

Well after a little more searching, the problem with the condenser blower fan motor on the OTR air was the CIRCUIT BREAKER. I checked them three times, but there was no power to the unit. Then a technician says you can't just "push" them in, you have to really "bump" them pretty hard to reset them.

The good news is no parts or labor incurred, but now it makes me think how stupid I have been not having the OTR air thru the fall and the only problem was a simple circuit breaker. And I knew there wasn't an electrical problem that caused it to trip because it popped out shortly after I encountered a monster set of new highway speed bumps at night that the State of Oklahoma installed before a flashing yellow light. I guess I should have taken a hammer to the stinking thing. :eek:

Anyone know what the proper circuit breaker resetting protocol is?

[ken&ellen]

Depending on the manufacturer, some trip in a neutral position and require that you switch to the off position prior to going to the on position, others have a visible trip flag to indicate a fault. Brute force should not be required unless you are dealing with 250-400 amperes in larger molded case circuit breakers.:confused:

[Jerry Winchester]

If only it were that easy.

You will soon find an assortment of circuit breakers on your coach. Some are thermal reset (they trip and reset on their own) some are the Klixon type (similar to airplane ones), some are as you described, the 110-220vac load center type and then there are these monster push botton breakers all over the coach, especially if you have OTR air. In the engine comparment, in the bays, in all kinds of assorted places, or at least in the Royale conversion.

The bigger the amperage, the bigger the button and I guess the harder to reset. I have enclosed a photo of a small 4 amp, so the corresponding 90 amp is 5 or 6 times as big.

[Jon Wehrenberg]

Jerry,

That condensing fan CB might be a weak point in the system. At least now you know about it and if the fan quits and the AC warning light comes on you can reset it, but if it happens again you should plan on replacing it.

I ran into that problem on my old coach and after determining there was no problem with the circuit I replaced the breaker and the problem went away.

To Ken and Ellen, and all, those big red breakers sometimes do not even looked like they tripped. Unlike some CBs that stick way out or in some way are obvious they tripped these may look completely normal. The only answer when trouble shooting is to look for power on the circuit. When I have had to reset mine I can't put enough pressure with my finger or thumb so I use something like a screw driver handle or something similar I can really push hard on to reset the CB.

Jon

[Jerry Winchester]

I have to think after running it for 6 hours, hitting those teeth rattling bumps had to cause it. I didn't get 200 yards from them when I am sure the pressure on the compressor rose because of the condenser fan being off and the warning light came on as it shut the compressor down. It even dislodged the CB speaker which is inconveniently located in the plenum behind the CruiseAir over the driver's head. Now I have to figure out how to pull the stinkin trim and air intake off so I can reattach the speaker which is now massively annoying as it rattles right above my head.:mad:

[Jon Wehrenberg]

Only time will tell, but I suspect the CB is getting tired. It's possible a rough road may have caused it to trip, but absent an electrical cause I would still stick with my suspicion the CB is nearing the end of its useful life.

BTW, the brushes in the condensing and evaporator motors are a service item. It might be worth your time to pull one of them. In the meantime I will look up the length Prevost calls as a minimum.

[Jerry Winchester]

Okay Mr. Photo Post-a-saurus, how do you pull the brushes to check them? Is it real evident or is the issue getting them back in (unless you know the Delcotron trick)?

I also bid on a brand new condenser blower motor on EBay this week, but it went above my gold room parts supply price. I figured it might be a handy part to have around when I thought mine had crapped out.

[Jon Wehrenberg]

They are accessible behind small black metal plates. Some are hard to get at and in my old coach the entire assembly had to be loosened to get access to the brushes in the rear.

To check you only need to pull one.

I will check the manual and pull one of my brushes and give you the real pertinent poop, and post it later. I don't want to rely on my memory because the last time I monkeyed with them was more than ten years ago.

Your Delco reference suggests you have been playing with brushes on the GM alternators and using the hold-em-back with the toothpick trick.

[Kevin Erion]

My 99XL has a dual pane glass window with the sliding portion to the rear. There is moisture getting in-between the 2 pieces of glass, any easy fixes?
Kevin

[Jerry Winchester]

Kevin,

If you are referring to the driver sliding window, mine has the same problem. Moisture gets trapped in there and it fogs up. This rates right up there with the loose turn signal problem that I just fixed, but I don't know how to handle this one. If someone on the board doesn't know, I will hit the glass man up and post the findings.

Jon,

I will pull one of the brushes when you have the poop and yes I have put brushes and diodes in several GM alternators and yes I used a toothpick to hold the brushes back. Old indian tricks are worth knowing. We also used gopher matches with the heads clipped off to hold the rubber block-to-head gasket on the 8V92's and 71's to keep them set as we put the heads on.

[Kevin Erion]

Jon,
Yes, that's the one. Thanks for the help.
Kevin

[Jon Wehrenberg]

My 99XL has a dual pane glass window with the sliding portion to the rear. There is moisture getting in-between the 2 pieces of glass, any easy fixes?
Kevin

I think I will have to get in line at the Prevost window store. My fixed side windows are fogging. They are glued in place. The last time I replaced one the adhesive was Sikaflex. Warm it up to make if flow easier. The windows are available from Prevost, but before I go buy one I am going to stick something in the sealer between panes like a basketball air nozzle, pull a vacuum on the window for a day or two, inject a little welding gas into it and try to reseal the perimeter. I have nothing to lose but a little time.

I'm going to do it after the POG, and I will photo and post everything. If it works I will write the procedure. From past experience this is a job replacing a glass that just takes a utility knife, patience and a tube of sikaflex.

[Jon Wehrenberg]

Jerry,

The manual says the brush length should be 3/4" or 19MM. To access the brush is a less than one minute job (for checking).

I am attaching a photo of the brush with the band clamp removed to the side.

On my 97 is a band clamp over the brushes and it is held in place with a pair of spring loaded clips. Pull a clip against spring tension and the "feet" of the clip will come out of the holes in the band and you can slide the clamp out of the way.

Lift the spring holding the brush in place and then slide the brush out.

As long as it is greater than 3/4" (19 MM) it is OK. The new length is 1 1/4" (32 MM).

The picture is of the condensing fan and the evaporator should be the same.

[mike kerley]

Jerry and Kevin,

Moisture in between glass layers is a common problem (so I've been told). I had my driver window changed by Prevost at a rally. Cost about $400 including labor.

they had several in stock on there truck and said they change them frequently. Had to do it, as I could not clearly see my mirror.

[Jon Wehrenberg]

Mike,

That moisture gets between all our windows because the seal has failed. I replaced one at Prevost once, and from that point on I did it myself for the very reason stated in your post. They are too expensive. If they failed on a 1987 coach, and then they failed on my 1997 coach there is nothing that can convince me the windows sold in 2006 are going to be any better.

By pulling a vacuum I hope to evaporate and remove the moisture, and by resealing the space between the two panes of glass and filling that space with dry (free of humidity) welding gas (I have argon, but nitrogen, helium or even a mix) there should be no more condensation until the seal is breached.

My rear TV camera had a glass cover and going from cold western NY down to FL was sure to form condensation which wouldn't go away so I made my own double pane glass and never had a condensation problem after that. I haven't tried it on the side windows yet, but I will and if successful as I pointed out earlier I will post the method.

[Jeffery Raymond]

On the curbside, you will find a box likely in a panel on the upper right hand side. Usually the middle solenoid is the first to go; there are little bimetal connections made inside of the silver solenoid, I think it is # 28. A good and simple test is to have someone run the OTR for a couple of seconds while you check the feed side amperage and then the output amperage. It should be putting about about 100 amps when the switch for the AC is on. If not, the fix is to simply replace the solenoid, about a 15 minute job.

Or you can go to a Prevost Car facility at about $2000/day and have them fix it.

[Just Plain Jeff]

You're not gonna like this, but the only proven fix to the whitening of the pilot and passenger window is to replace same. There was some geek who thought that he could drill a tiny hole and create a vacuum and remove the moisture and quickly reseal it, but I haven't seen anyone pull that one off yet.

As to the OTR, you will also find on the street side, center, a solenoid which controls the fans. That little bugger will go sometimes, which will kill the OTR air and make it seem that your motors are kerplunk. If the CB is good, the next place to look is the solenoid. Easy and quick fix: Take the old one out and put a new one in.

[Jon Wehrenberg]

Since the bus will be sitting for a while, this geek will eventually get around to pulling my fogged up door window and evacuating it, pushing a little argon in it, and attempting to reseal it.

If it works and lasts even half of the 7 to 10 years these things seem to last it will be worth it. The price Prevost wants you to pay for a product guaranteed to fail is absurd.