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Dash Air Repairs
#11

Yea it does seem a bit over the top. However, I'm speculating here, on most vehicles the condenser sits right behind the front bumper and could easily be damaged in a frontal accident. That same accident could also provide an igniting spark in the same place at the same time. The refrigerant filled parts on my coach are further back and inside a steel box. In my opinion that reduces the likelihood of a problem but doesn't eliminate it. It comes down to a careful assessment of the likelihood and severity of a problem and one's personal risk tolerance.

Jon Kabbe
1993 coach 337 with Civic towed
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#12

I'm confused by the hardware I've found in my dash air system. There is an inline reservoir between the condenser and evaporator coils. This location is used with a thermal expansion valve on the inlet of the evaporator. I cannot find a thermal expansion valve. I do have a 1" metal cube plumbed into the tubing between reservoir and the evaporator, I'm guessing it is some kind of orifice restrictor. However, with orifice restrictors the reservoir in the system is between the evaporator and compressor to prevent liquid refrigerant from getting to the compressor and damaging it. I cannot find such a reservoir, nor can I find any documentation anywhere of a system designed with two reservoirs. You one either upstream or downstream of the evaporator but not both. So fundamentally I'm seeing a system that doesn't align with standard documented designs and is a functional mystery.

I also cannot find any pressure switches anywhere in the refrigerant flow. If there are none, then the compressor runs continuously whenever the system is turned on regardless of the fans on the evaporator being either in high or low speed. I just cannot imagine how such a simply constructed system can function much at all. I may be missing something and need to spend even more time under the coach sussing things out, but I seriously doubt it.

Do any of you have insight into this 93 version of this system?

Jon Kabbe
1993 coach 337 with Civic towed
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#13

I like you do not like things that don't work. The Dash A/C didn't work on our '82 so I started doing a similar research. Basically pumping the refrigerant the length of the coach with all of the potential leak points I really looked at the system.
I decided that it wasn't worth my time and money for a 30 year old system that blew cold air at my knees.
I use my overhead A/C when needed and it doesn't hurt these old knees. Like Richard's you could hang meat when it is on at temps over 90 Degrees. Having said that I believe that Richard helped Clarke get his unit working.

Steve & Patti, Bonnie and Tucker
1982 Newell 38' Classic, DD 6V92
cocktails for as many will fit in the site, dinner for as many can sit at the pick-nick table and sleeps 2 since I fixed the couch
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#14

Thanks Steve, yeah it is a system with a myriad of potential leak spots. The fact that it is still holding some pressure after who knows how many years gives me hope. However, like you I'm unwilling to continually invest in it to keep it running so what I may do is invest a bit now and if it fails just remove it all from the coach to lighten the load.

Jon Kabbe
1993 coach 337 with Civic towed
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#15

77, I left all of the parts in place in case a future owner...maybe like you?....wanted to try and get it working. I simply removed the belt from the compressor so that my little V-6 (6V92) didn't have any possible extra load.
Good luck to you!
By the way, it doesn't hurt to exercise the Generator.

Steve & Patti, Bonnie and Tucker
1982 Newell 38' Classic, DD 6V92
cocktails for as many will fit in the site, dinner for as many can sit at the pick-nick table and sleeps 2 since I fixed the couch
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#16

Steve: leaving the stuff there probably makes more sense as it really doesn't weigh that much compared to the coach. Removing the belts would be a smart move, thanks.

Jon Kabbe
1993 coach 337 with Civic towed
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#17

A bit of progress. Nothing was powered electrically so I went is search of 12v. There was nothing connected to the back of the dash mounted control panel that switched 12v on and off as the a/c was turned on and off. Found a white wire with spade connector just hanging in the area and tested continuity to the blue control wire on the "condenser" rely and found continuity (no idea why or where the color change takes place). Now it all mechanically operates and there is some cooling though I haven't yet assessed the proper freon charge since it started raining. I suspect it will be low and I'll still have to decide on what to recharge it with.

With all this stuff working I'm worried I'm getting close to the point of selling it. My pattern has been to buy a coach with the intention of keeping it long term but then I find it needs many repairs which once fixed seems to trigger an irrational response that I need to change to something else. I really don't understand this craziness but I can feel the beginnings of the itch - insanity!

Jon Kabbe
1993 coach 337 with Civic towed
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#18

I am replacing all of the components in my dash a/c compressor,dryer, expansion valve etc. Creslie said 4 pounds of freon total in system , but did not mention how many oz of oil? Does anyone have an answer?

Ed and Penny Thomas
Anna, TX
98 Newell
coach #490
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#19

That's a good one. The technically correct way to do it is to charge the system, run it for 30 minutes, evacuate the charge, and pour the remaining oil out of the compressor. Sanden literature will tell you how much should be in the compressor. You compare that to what was in the compressor and add oil accordingly. That does not sound like a great process.


There is info on the Evans tempcon site under system oil allowances that should give you a decent estimate. I would post the link but I'm not smart enough to do that using an ipad

Here is the address http://www.evanstempcon.com/tsg_oilallowance.php

This is a great technical site for dash AC systems.

Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home Cool )
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#20

Dear Fellow Newell Owners, We did change our dash air system from R-12 over to R-134A in our #277, 1991 coach. It cools OK, but the air flow is almost terrible! Worse, what little it has goes to about zero when we begin driving.

So far, I've determined that the aerodynamics of the front lips creates a low pressure area behind it, where the dash air box has big drain holes. I connected 2' PVC pipes with elbows to feed the drain holes and retained the little air flow while driving.

The best I can tell as I viewed the air box when Newell removed it because I ask them to verify the air box is unobstructed, is that Newell did a terrible design job with the top of the air box. The tree blower motors in there blow through restrictive holes into a rectangular channel with a sliding bar to select the modes and air vents. Poor for air flow. I intend to retain the three blowers, but only run one at a time to directly feed the different vents. Each vent will feed a 3" duct which y's to 2 1/2" tubes to feed the vents.

I hope to do this project in the next couple of months. I'll post as to results.
deg
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