Air Conditioning/Inside the Pipes

[Joe Cannarozzi]

We picked up the bus Friday A/C repaired. Turned out didnt need a compressor at all. The machine they used to install the freon was miscalabrated and there was too much freon and it was returning to the compressor liquid and locking up. Next dragon, bushings and then awnings. They found there error when another A/C system devoloped the same symtoms for the same service with the same machine after doing ours!

[MangoMike]

See Joe,

Sometimes you do have good Karma.

MM

[Joe Cannarozzi]

Thank you oh wise one The bus thermostat has to be turned down or it gets too cold. This is good! The drivers air doesnt seem to do as well. Is this normal? Plenty of blower just doesnt seem to get real cold?

[Ray Davis]

Having just had my drivers air worked on, mine blows very cold now. One thing I learned a week ago, which confused me a bit. I had a little fogging going on driving home a week or two ago, so I turned the dash control to defrost, and turned the thermostat up to heat the air.

Later when I turned it back, I noticed that my dash A/C wasn't blowing very cold. Given that I'd just had it worked on, I'm still sensitive to whether or not it's functional.

Well, I guess it turns out that turning up the thermostat lets engine heated water into the core, to warm the air. I guess that makes sense. What I didn't realize, that when I turned it back to cold, it doesn't happen instantly, as it just stops putting hot water in the core, but that the hot water remains until the 190 degree water itself is cooled.

So, make sure your thermostat is all the way down. I thought my dash was broken again when this first happened!

ray

[Joe Cannarozzi]

These A/C compressors do not cycle on and off like you see in cars and trucks. When you turn the A/C on the compressor clutch kicks on and STAYS ON. The only way to regulate temp. when it starts to get cold enough is to introduce a little heat. If I had to guess I would say due to its massive size it would be too hard on the clutch for it to be kicking in and out all the time.

[Jerry Winchester]

Joe,

I would be curious to know if the recomended practice for turning the system on is to do it at idle and not running down the road? I make it a practice to not turn mine on above an idle, but I don't know if that is right. I just figured slamming it on from zero to 2000 rpm couldn't be good for it given the mass.

But that could just be because I have been hanging around Jon too long.....

[MangoMike]

Good quesion. I'm always flippin' mine off and on as we motor down the road. Especially hitting those big hills, off it goes for more HP. Dad it's too cold - off it goes in hopes of saving a little fuel.

Mike

[Joe Cannarozzi]

Jerry, Im just trying to apply a little mechanical common sence. I think what your doing is sensible. Mango, there is a thermostat to keep your dad happy and if you have a underpowered issue mabye you need an 8V hu! How fast ya need ta get up the hill anyway?

[Jon Wehrenberg]

I don't know if the clutch is adversely affected by turning it on when the RPMs are high, but my guess it is designed for that. On my old coach it did cycle so that is why I say that.

Joe, if you can use a mid or lower driver air fans speed. I think it is more efficient at cooling the air at lower speeds. Let us know for sure. I always use a mid to low speed on mine just because I hate the noise at higher speeds, and I think I noticed once that slower speeds are better at providing cold air.

[Joe Cannarozzi]

Our kitchen unit is having a problem with the fan speed. It has been there since day 1 and am just now getting to it. The problem is the the blower speed for the evaporator. It will run on full speed only and if we try to slow it down the blower will stall.

There are 2 possibilities I am concidering. First the capacitor for the blower motor or second the reostat at the control panel.

Custom or built in both do not even come close to describing how this unit is burried in the upper kitchen cabinats. Only after attempting multiple times to dimantel them sufficiantly enough to acess the blower I have finally gotten to the "evaporater unit" that contains the blower where the capacitor resides. Unfortunatly I once again had to stop and reassemble again because it looks as if I'm gonna have to unhook the feron lines and completly remove the unit in order to remove the top of it to access the blower and capacitor.

Has anyone had this trouble before or can confirm for me what component is bad before I go and open everything up again? What is stopping us from running the blower at slower speeds? I'm leaning towards the capacitor and would hate to find out its the reostat that would take litterally minutes to replace.

A few side notes.
First I've got the literature The converter put in the documents for the blower, its a Dayton and I'v got the part# for the capacitor, sweet hu!

Second I've discovered these blowers have oil points just like the blowers at the condensers. I'd hate to think that the converter expects owners to go to such great lengths on a yearly basis just to service them. On the other hand this one is 21 years old, never been oiled, and seems to sill be tight. There ARE oil points on these nontheless.

Third there is a fine wire screen across the front of all the evaporators to keep them clean and they plug up FAST. We have only had our bus for 1 season and I just rinsed it off for the third time and it was very dirty yet again.