What should the connected subject gauges (Blue LP and Red HP) read for a fully charged system in my coach 2001 U320? Cannot find anything in the FT documentation box.
The measured temperature at the dash outlets is 62 degrees and I believe it should read around 42-45?
When I replaced my compressor and expansion valve I was getting around 20 on the low side (blue) and 150 on the high side (red) the ambient temperature was around 80 deg. The thermostat cuts my compressor off when the register gets to 40 deg. These numbers are way off from searches I did on ref. 134a maybe because we have the condenser fan running all the time or some other characteristic of the coach causes the difference. I first used the 65 psi. low and 250 high when I charged it and it never go cold. I then lowered the pressure until I had 40 deg. at the register and made a note of the pressures for future use on my coach.
The pressures and temperatures are subject to a correction for ambient temperature. I will try to find a link to a chart my chart is at work.
Pressures will go up and down based on temperature of the condenser and evaporator--which change based on ambient temp, airflow, cleanliness, etc.
You are technically charging to subcool method with a TXV. Fixed orifice, use superheat (or grab the return line and make sure it's cool).
If you are trying to achieve a certain pressure, you are chasing your tail. The good news is that this system is large and because it is a TXV is forgiving to not achieving exact charge amount. I think mine took around 2 or 3 lbs to get what I was looking for, but I can't remember exactly.
The concept is to achieve enough refrigerant in the system to ensure the TXV is getting subcooled liquid. Too much charge, and the liquid backs up into the condenser and possibly to the compressor.
It seems that with that pressure split there may be something amiss. Are you getting good heat transfer at the condenser and evaporator? Is the hit cold blend door going to full cold? Was there an inline filter in the system?
Looking for a list of parts.
Need Receiver dryer part# also compressor part# .found receiver/dryer loaded up. flushed lines already. Parts sources? Thanks
Compressor number Seltec 488-46018 expansion valve, MEI 1600, drier RD 7127
These numbers fit my 1999 U320 I think I found the numbers on Barry's website or on the forum search