maiden voyage

[Darrell and Linda]

Just got back home from a 3 week, 5000 mile trip. Five provinces and five states. Great trip for the maiden voyage. Everything ran perfectly. The OTR needs attention, recharge but I suspect an upgrade will be on the agenda but will I'll deal with that later. The three cruise airs worked fine.....good to go in the northern areas at this time of year.

Question: Hot flashes. I know what the wife means now...... I sure someone can answer this. Traveling down the road for a couple of hours, I'll get flows of very warm air in the drivers compartment, even with the front and mid cruise airs working. It comes and goes. Every 10 -15 minutes and continues on. I thought it might be the two vapourisers? working hard in the front, below the cabin. .......but I turned off the cruise airs and it continued,,,,,,, even over a long cool down period of time...... any ideas? Is this common.

Over the three weeks and all the country we covered, I only saw four other prevost conversion coaches on the road.......
Alberta, Saskatchewan, Manitoba, Ontario, Quebec, NY State, Michigan, Illinois, Minnesota, North Dakota

[Joe Cannarozzi]

Darrell drop your front bumper and look over to where the bottom door hinge is there should be a box built around it and sealed up good.

If that lower hinge enclosure is compromised it will cause a draft.

Also the control for outside air or recirculate leaks like a screen door on a submarine, even on recirculate it is still letting in much hot air. The damper sucks.

While the bumper is down you can tape up that intake it is on the upper edge of the bumper compartment. Duct tape 10 inches.

[gmcbuffalo]

What do you mean by vaporizers? Did you have the fresh air vent closed? You should be able to close it by turning a knob on the lower center of the dash.

GregM

[Darrell and Linda]

I'll drop the bumper and check that out tomorrow. Your right, It didn't make much of a difference playing with the recirculation or fresh air controls.

Thanks

[Darrell and Linda]

Vapourisers? Condensers? I'll figured that out later but the forward and mid cruiseairs are located below the cabin behind the front bumper.

[Joe Cannarozzi]

The half of the cruisair that is in the basement is the condensing unit and the evaporator is the component in the dash.

Darrell I had a couple other holes I sealed up too.

Prevo cut a square hole where the a/c lines come up from the bumper compartment that was letting air in.

The last one you will not get to without considerable effort.

[Jon Wehrenberg]

Darrell,

This is a little more specific to your Liberty.

Your fron and center cruise air condensing units are behind the bumper. They are not enclosed except within their own housing.

They are designed to pull ambient air through themselves and pass it through the copndensing coils and discharge that heated air out the bottom. You should make sure the coils are clean and not covered with an accumulation of debris.

Use a soapy mix of something that can clean the coils. If you use Simple Green use the kind designed for aviation because the regular stuff attacks aluminum. Rinse it well with a hose but not a hard spray. There is a fan motor, and a couple of capacitors in there so don't go crazy with the water. You want to use a volume that wets and rinses the coils, but does not get the interior of the condensing unit completely soaked.

That is all you can do to insure the most efficiency.

What I think was happening was the condensing units were not getting sufficient cool air and the units were shuitting down. If the units cannot cool properly the internal freon pressure rises and when it exceeds a certain value the Cruise Air compressor ceases to function. Your warm air was heat being given up by the evaporator coils. As soon as the freon cooled down, pressures dropped and the units begain cycling as they should.

We have discussed the inability of Cruise Airs to function as over the road air conditioners as well as roof air units do. Roof air units are not bringing air heated by the highway into them, but clean cool air from 12 feet above the highway. The Cruise airs work well when pulling air from beneath a parked coach.

If your OTR does need a recharge try to stick with R-12. It is pricey, but if your system checks out it is the most efficient refrigerant. If you switch to 134-A it is cheaper to recharge, but you lose about 15% of the systems performance. I would guess that the system has a small leak at the seal behind the clutch on the compressor. Look for evidence of that in the form of oil behind the clutch. That is an easy fix and a competent guy can change the seal in a couple of hours or less. Test with nitrogen before recharging an if the system hold pressure you are good to go.

[truk4u]

Darrell,

Make sure your shutters are open when using the cruiseairs while driving. The default position is closed, so you have to use the button on the dash to open them while driving. If the shutters are closed, the cruiseairs may shut down like Jon stated. When I open my shutters while driving, I also get a slight blast of warm air. All of this is providing your vintage has shutters like mine.

[dreamchasers]

Darrell,

Since I do not have cruise airs, my experience is limited with these units. However, if you are using the Prevost dash air at the same time to circulate or generate additional cold air in the drivers compartment, be aware that Prevost uses a solenoid to control hot engine water from the dash air heater core. The dash air heater core is in series with the AC evaporator, so any leaks through this solenoid, intermittently or continuous, will manifest itself in warm air coming through the dash air vents.

I recently overhauled my dash air and could not get really cold air to discharge from the vents. When I first started the coach, the AC vents would register 47 degrees discharge air(Great!), then after running the engine for 5 - 10 minutes, the temperature would rise to 55 degrees. My 'extensive' investigation revealed the heater water supply line going to the heater core was hot, 107 degrees, but the heater discharge line was 68 degrees. The dash ac system was cooling the leaking hot water through the heater core/evaporator assembly, thus the high discharge temperatures from the vents. This was a tricky issue to find. In my humble opinion, rubber is the enemy of these older coaches.

Problem was solved with the purchase and install of a solenoid rebuild kit from Prevost.

Though you would like to be aware of this small detail that can effect the AC cooling in the drivers compartment.

Hector

[gmcbuffalo]

Hector
Where is this solenoid located? My Dash heater/AC has a knob that controls it (I think). All the way clockwise there is click and it stops. Turn it CC and it has a large range of motion. The last time I used the coach I didn't notice much differences in the position of this knob. There are two separate knobs for the fans. I forgot to put a manual lever in the engine compartment in the summer mode. The reason I ask where this solenoid is located is I am wondering if I have solenoid or just a manual lever.
GregM