powerboatr
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2008 Damon tuscany on a freightliner raised rail chassis.
History.
First three years of ownership starting in 2009, the a/c system kept loosing pressure and the rv place had to increase the low side hoes length by 4 feet as the original line was to short and engine tq kept pulling hose to the point it leaked at compressor.
They pulled vac on system over night and then filled with refrigerant the next day.
Three weeks later a/c failed again. This time they replaced dryer, condensor, compressor and expansion valve and flushed the system.
A/C worked great for about 1 year, then started tapering off in performance, then would would freeze up or not cool enough.
TXV valve was replaced again.
So for every year since 2011 I have had to have it topped off with a few ounces or a few lbs to get to the cool through the summer.
This year I am at the last straw and feel the need to rip out and start over. in preparation of the upcoming trip, I started the engine turned on ac and just got ambient air.
So the next day I hooked up gauges static was over 60 and high was right at 125.
as soon as i started engine, a/c clutch was not engaged, the gauges dropped to -20 on low and 145 on high with occasional movement a few lbs.
Gauges steady no pulsing.
So i said lets try to add some refrigerant to see if it the clutch will engage, put in a whole 12 oz can, as I was adding refrigerant the high would occasionally move up or down in the range of 130 to 165 psi and the low i kept at no more than 40 psi while the refrigerant was going in. so when can one was used up, i shut off the valve to see what the pressures where, low was -15 and high was 135 steady.
And my condenser was getting getting warm to the touch and felt like it was climbing in temp. dash air temp was ambient of 77F, as this was the coach temp from the roof top ac.
So I still didn't hear the engine compressor engage or the condenser fan come on.
the system has over 80 feet of hoses, as the engine driven compressor is some 39 feet from the condenser and evap and dryer up front.
Now I had one more can and decided to try to add it and get the compressor to come on.
It went in and compressor never engaged, but condenser got noticeably warmer, especially at the high side entry.
The txv valve is sticking out of the evap coil and the temp bulb is tucked into the plenum to monitor evap coil temps.
The high side pressure port is about 3" from the txv valve.
Here is where it gets WEIRD.
The txv valve starts getting frosty as in ICED over and is dripping water as it tries to freeze farther down the line. I stop adding refrigerant and the low side is now -10 and high side is 160 and moving slightly high, then slowly drops a few pounds, the compressor still has not come on. The condenser high pressure line is now very warm at the condenser attach point
the low side lines are ambient for outside which was above 90f.
So I said CRAP out loud and shut off the engine and started disconnecting lines
the low side quick connect came off with no fan fare, but the high side shrader valve stuck in the OPEN position when i disconnected the high side quick connect, which promptly bled off a ton of refrigerant and made one hell of a mess as there seems to be some stop leak stuff in the lines and it looked liked expanding foam
I have never used refrigerant with stop leak, but i have no idea what the service center did.
So now, my plan is to replace the sticking shraeder valve. But first maybe do some sort of flush and then apply vacuum for a few days. Then add in die and pressurized both sides with shop air to see if i can find a leak. Or should i flush the system, open up every fitting. replace the o-rings and try pulling a vacuum.
I have no idea where the leak is, to date i have put my hands and eyes on every fitting and have no seen any residue or oily stuff.
Thanks
(edited by the grammar police for readability)
History.
First three years of ownership starting in 2009, the a/c system kept loosing pressure and the rv place had to increase the low side hoes length by 4 feet as the original line was to short and engine tq kept pulling hose to the point it leaked at compressor.
They pulled vac on system over night and then filled with refrigerant the next day.
Three weeks later a/c failed again. This time they replaced dryer, condensor, compressor and expansion valve and flushed the system.
A/C worked great for about 1 year, then started tapering off in performance, then would would freeze up or not cool enough.
TXV valve was replaced again.
So for every year since 2011 I have had to have it topped off with a few ounces or a few lbs to get to the cool through the summer.
This year I am at the last straw and feel the need to rip out and start over. in preparation of the upcoming trip, I started the engine turned on ac and just got ambient air.
So the next day I hooked up gauges static was over 60 and high was right at 125.
as soon as i started engine, a/c clutch was not engaged, the gauges dropped to -20 on low and 145 on high with occasional movement a few lbs.
Gauges steady no pulsing.
So i said lets try to add some refrigerant to see if it the clutch will engage, put in a whole 12 oz can, as I was adding refrigerant the high would occasionally move up or down in the range of 130 to 165 psi and the low i kept at no more than 40 psi while the refrigerant was going in. so when can one was used up, i shut off the valve to see what the pressures where, low was -15 and high was 135 steady.
And my condenser was getting getting warm to the touch and felt like it was climbing in temp. dash air temp was ambient of 77F, as this was the coach temp from the roof top ac.
So I still didn't hear the engine compressor engage or the condenser fan come on.
the system has over 80 feet of hoses, as the engine driven compressor is some 39 feet from the condenser and evap and dryer up front.
Now I had one more can and decided to try to add it and get the compressor to come on.
It went in and compressor never engaged, but condenser got noticeably warmer, especially at the high side entry.
The txv valve is sticking out of the evap coil and the temp bulb is tucked into the plenum to monitor evap coil temps.
The high side pressure port is about 3" from the txv valve.
Here is where it gets WEIRD.
The txv valve starts getting frosty as in ICED over and is dripping water as it tries to freeze farther down the line. I stop adding refrigerant and the low side is now -10 and high side is 160 and moving slightly high, then slowly drops a few pounds, the compressor still has not come on. The condenser high pressure line is now very warm at the condenser attach point
the low side lines are ambient for outside which was above 90f.
So I said CRAP out loud and shut off the engine and started disconnecting lines
the low side quick connect came off with no fan fare, but the high side shrader valve stuck in the OPEN position when i disconnected the high side quick connect, which promptly bled off a ton of refrigerant and made one hell of a mess as there seems to be some stop leak stuff in the lines and it looked liked expanding foam
I have never used refrigerant with stop leak, but i have no idea what the service center did.
So now, my plan is to replace the sticking shraeder valve. But first maybe do some sort of flush and then apply vacuum for a few days. Then add in die and pressurized both sides with shop air to see if i can find a leak. Or should i flush the system, open up every fitting. replace the o-rings and try pulling a vacuum.
I have no idea where the leak is, to date i have put my hands and eyes on every fitting and have no seen any residue or oily stuff.
Thanks
(edited by the grammar police for readability)
Last edited by a moderator:
