OTR air

[sticks]

Experiencing a problem with my OTR heat/air on my way from Iowa to Florida. After 3 days of fog, rain, and road grime, the passenger heat/air unit would shut off seemingly when pulling off interstate and driving slowly or ready to stop. It would not turn back on pushing the on/off button for 30-60 seconds. Is something overheating and thus shutting down? Are there filters under the bus that have gotten dirty creating this problem? I.m all ears.thanks!!

[Jon Wehrenberg]

What is passenger OTR?

I am not up to speed on later model H3 OTR systems, or how Prevost set up the controls. My controls for OTR consist of a rocker switch to set heat or AC, and controls for the temp and fan speed.

The driver's portion of the system is the front ducts only, and for heat can be run without the main OTR switch being on, but the AC function requires the OTR AC function to be on.

I have no button to push or reset.

You don't say whether you were calling for heat or AC. Any warning lights? Is it the fan that quits, or does the fan continue to run but the temperature fails to heat or cool?

It is highly improbable that a few days running in crud has any affect on the system because these systems run on commercial buses that run in those conditions for a long time with minimal maintenance.

[rfoster]

You need an A1 Fan.

[jack14r]

Sticks,The switch for the dash as well as the switch for the rest of the coach must be on for the system to work,my 05 Liberty would show a webasto light on the dash whenever the heat came on,this indicated that the webasto pump was on which circulated the hot water to the heat exchangers throughout the coach.I would check the Webasto pump as well as solenoids that allow the coolant to flow to the dash heat exchanger.Being in warranty,this is a Liberty job.

[sticks]

mystery solved. There are two small wires on top of the alternator that feed the OTR system. One or both can vibrate loose over time or break , either way, the OTR stops working . In my case , I probably had one to start with which intermittently stopped passenger side but by the next day the whole system went belly up for good but I was able to limp into Stuart, Fla. in 84 degree weather and get it repaired.Turning generator on, opening front shudders and running Cruise airs helped cool the back of the coach, but doesn't do anything for the driver( me).

[GDeen]

mystery solved. There are two small wires on top of the alternator that feed the OTR system. One or both can vibrate loose over time or break , either way, the OTR stops working . In my case , I probably had one to start with which intermittently stopped passenger side but by the next day the whole system went belly up for good but I was able to limp into Stuart, Fla. in 84 degree weather and get it repaired.Turning generator on, opening front shudders and running Cruise airs helped cool the back of the coach, but doesn't do anything for the driver( me).

Imagine that was especially true in the H.....

[garyde]

Hi Sticks. If your OTR is working for the rest of the Coach, it may be a vent problem only. I have heard that the front vent hoses can collapse or seperate.

[Jon Wehrenberg]

Huh???????

Wires off alternator make the OTR work???????

[JIM CHALOUPKA]

How about wires off alternator and nothing works.





jim

[Jon Wehrenberg]

The alternator on my bus has three wires, the big cable going to the isolator, a field wire to the regulator, and a relay wire.

If they are loose the bus loses voltage in the chassis batteries, and the AC is a heavy load pulling juice from the batteries, but before the batteries go dead there is a big red warning light on the dash saying the alternator ain't alternating.