You are not logged in or registered. Please login or register to use the full functionality of this board...


House A/C
#11

Four pounds of 134a is about right for the dash system. Your low side switch should not be cutting out at 30. It should cut out around 15 to 20. Can you jumper the switch or run a 12v hot to the compressor to force it to run long enough to get lo and hi readings? I can think of several possibilities. One, you have a huge leak and don't really have 30 psig when the compressor is running. Two, you have too much in the system and the hi side switch is cutting you out. Three you have a clogged expansion valve.

Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home Cool )
Reply
#12

(08-04-2015, 09:43 AM)Richard Wrote:  Four pounds of 134a is about right for the dash system. Your low side switch should not be cutting out at 30. It should cut out around 15 to 20. Can you jumper the switch or run a 12v hot to the compressor to force it to run long enough to get lo and hi readings? I can think of several possibilities. One, you have a huge leak and don't really have 30 psig when the compressor is running. Two, you have too much in the system and the hi side switch is cutting you out. Three you have a clogged expansion valve.

We tried to replace the expansion valve, tried two valves one was a four seasons cross that Creslie Clark gave us and neither one would screw on the end. So we cleaned the old one and put it back on. We also jumpered the low pressure switch and the clutch stayed on , but unit would not cool. It will only cool while you are putting freon in. As soon as you stop,it will run for 20sec and clutch will disengage at just below 30 psi

Ed and Penny Thomas
Anna, TX
98 Newell
coach #490
Reply
#13

Can you provide high side readings?

Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home Cool )
Reply
#14

(08-04-2015, 09:30 PM)Richard Wrote:  Can you provide high side readings?

I have asked Ryan if can recall the high side readings. We are at Santa Fe Skies RV Park with the MH and be hear until the end of the month. So will not be working on it until we return to Dallas.. Just trying to get some idea or what to do when we return.. Thanks for trying to help us. Rolleyes

Ed and Penny Thomas
Anna, TX
98 Newell
coach #490
Reply
#15

Ok

If we are generating a list of things to look at. If the high side is above 250 then the exp valve is still stopped up. You can take the exp valve to a place in Fort Worth called cranky ape and they will physically match it for you. That's exactly what I did when I lived in Fort Worth.

I also had a weird problem with the connector to the compressor on my current coach. The connector would intermittently provide voltage to the compressor clutch. It took me a couple of try's to find that

Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home Cool )
Reply
#16

Well Dave came and topped off my A/C . We got it working well. It cooled for a couple hours then I shut it down. A week later I fired it up to cool the coach down before a trip last weekend and I thought I smelled A/C oil around the compressor area. By the next day it would not cool. I'm suspecting a leak in the condenser. Not sure how to find it......

1993 Newell (316) 45' 8V92,towing an Imperial open trailer or RnR custom built enclosed trailer. FMCA#232958 '67 Airstream Overlander 27' '67GTO,'76TransAm,'52Chevy panel, 2000 Corvette "Lingenfelter"modified, '23 Grand Cherokee.
Reply
#17

Look for oily residue.

Soap bubbles

Inject UV dye and look with black light

Use a refrigerant sniffer

In that order of "effort"

Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home Cool )
Reply
#18

I would really prefer to keep the basement HVA/C operational as long as possible. Even when they are working I just don't get enough cooling to the front. I'm researching all of my options. Thanks to Rudy for the call yesterday as I had some questions concerning Aquahot.
Currently I am researching residential ducted mini-split systems. I believe some of the amateur bus conversion guys have used them with mixed results. My thought is to remove the obsolete dash air equipment and plumb the mini-split into the dash area vents. This would provide heat and cool using the invertor heat pump technology. Most seem to require 220V but I've seen a few 110V units. According to a home calculator I would need around 19,000 btu for the whole coach. Since I am planning for this unit to be supplemental to the current units I'm thinking 9-10'000 btu would be adequate.
I would welcome any thoughts pro or con!!!!

1993 Newell (316) 45' 8V92,towing an Imperial open trailer or RnR custom built enclosed trailer. FMCA#232958 '67 Airstream Overlander 27' '67GTO,'76TransAm,'52Chevy panel, 2000 Corvette "Lingenfelter"modified, '23 Grand Cherokee.
Reply
#19

According to Heco http://www.heco.net/maincat/compressors.pdf a Delco A6 AC unit will generate between 27,000 and 42,000 BTU's depending on engine speed (2,000-4,000 rpm). With all the glass surrounding the drivers area, I would be surprised if 9000 BTU's would provide adequate cooling. My Newell has 4-13,500 BTU basement airs and I wish it had more to cool it down faster during the Texas summers.

Michael Day
1992 Newell 43.5' #281
NewellOwner.com
Reply
#20

Dean,

The mini splits may eventually work their way into a potential replacement for many of the basement air Newells. After all the Dometic units are mini splits.

I am not sure that I understand what your objective is based on your initial comment. Is your objective to add supplemental cooling to the front for use while parked? Supplemental to the front while driving? Or to replace the entire cooling system?

Do you intend to drive the unit from the inverter(s) via the engine alternator or where you looking to direct drive the compressor from the engine?

If you want to put the mini split evap where the current dash AC evap is located then you are going to pump a lot of air flow out of a few vents which might be noisy, or restrict the flow.

I know it's somewhat not what you asked, but have you thought about supplementing your current basement air with one roof unit located as close the front as possible?

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


Forum Jump:


Users browsing this thread: 1 Guest(s)