[Michael]

Bumping this back up guys as I am running through some cold temps and we are getting into winter time.

RIght now I have to have the Dash HVAC set to FUL on the temp setting to get the heat light indicator and get hot air, and it is plenty hot without using the H20 circ button.

However, when you back off the temp setting to ANYTHING below FUL, 85, 84, 78 etc etc you get NO heat and no heat light, just ambient air.

This can’t be right, is there no blending, just either full on hot, which cooks the dash, or freezing feet.

GRRRR….This Prevost dash hvac is giving me the same feelings of rage as the XL2 ford headlamps….what were they thinking?

[Chas]

Greg the royale would go up or down with heat knob a little bit of heat or lots I never used the H2O button must be something wrong I think …

on another note I saw some replacement headlights at Fort Garry in Saskatoon that I think will work there are same size as old ones four little round bulbs HID two for low beam and two four high beam they are the square lens but up dated insides I am going to measure mine I think they will work I will let u know they are super bright about $3500 each but if they work it’s worth it to me

[Mike]

G-man,

My digital temp select is off quite a bit as well on both heat and air, but not as bad as yours on heat. The system doesn’t work very well when trying to blend to get to a comfortable temperature. Like yours, it’s either to hot or to cold. Next time I get near Prevost, I’m going to check if there is a calibration that can be done to get the temp closer to the set point. Someone told me the problem is a temp sensor that should be talking to the digital set point.

[Bill]

It should blend the heat or air as advertised, the hardest part is turning it on in the middle of the night when driving. Pull over and do it, keep your bus on the road. It’s very easy to push the wrong buttons when driving.

Later

bv

[Tom]

Talked to the helpful techs at Prevost who explained how the system works. Looks like it may be a bad temp sensor, I guess they need to test it againt a conversion chart.

So at FUL it will put out heat non stop no matter what cabin temp is. So that is what I have now, no blending at all.

Looks like a trip to Prevost is in my future, probably can’t sort this one on my own.

[Archived]

Tom, et al.

I went back and looked at the Prevost owners manual, it suggest always having recirculate on whether heat or AC.

I tried that and now the heat works a lil better than before allowing me to use a lower temp setting and watching the system try and modulate the temp.

So as normal the red heating light will come for about a few seconds, alowing hot water, then shutting off, awaiting a feedback signal from the sensor, then staying off or turning back on to allow more hot water, so it is acting as normal as was described to me by a Prevost tech.

Bottom line I am sure my sensor is still way off. Price of new sensor $30. New HVAC control module $700+. Time at Prevost to troiubleshoot minimum $100 I figure, so I may just gamble the $30 and try a new sensor, which is likely the issue.

[Archived]

Where is that sensor?

[Fred F.]

On an XL2 I think just near your right knee as you sit in the driver seat behind dash. I think I spotted it today as I pulled the right cover panel to re-epoxy the little cubby that the Tech link screen sits in. On the H it can be in that area or also upper left hand side of dash, there was a changover sometime early 2000’s if I heard the Prevost action tech guy correctly.

I will probably replace this week if I get by Mira Loma to grab one….those guys owe me a part that has been MIA for months anyways. Also I am tearing into dash later this week to update the original clarion stereo which I think is on its last legs. I may end up ditching the Alpine techlink monitor and replacing with a double din unit that will do techlink screens, all my cameras, XM radio, bluetooth GPS etc etc.

In other news, my wonderful dash AC went out a few weeks ago, I dug out old receipts from prior owner…hmm over $2500 in AC work in last 3 years at…..Mira Loma.

My brother and I pulled what I suspected was a bad low pressure hose off compressor today. Had a new hose made up here in Phoenix for $50, pulled a vacuum on it and seems fine, filled with 6 lbs 2 ounces and it blows nice and cold again, not sure how the temp sensor does with things on cold side, but I usually always have to have it on max anyways…prevost dash air…lulz.