Just a few 'hints' on re-charging a modern RV roof A/C.................
• These units are hermetically sealed at the factory for a reason. If they thought it a good idea to re-charge them like a domestic unit, there would be a pair
of Schrader valves soldered
into the high and
low sides of the refrigerant lines.
• Anything can be repaired.........but what is the real cost? After all, just about anything can be done......it's just a question of time and money.
• Clamp-on piercing valves (which are required to evacuate the refrigerant lines) are OK for just that purpose, but left in place, they will leak
and MUST BE REPLACED with silver soldered permanent Schrader valves.
• the proper process for the re-charge on a sealed unit is as follows:
1. apply 2 piercing valves
2. evacuate the system with a vacuum pump and certified recovery
4. silver solder permanent Schrader valves into the high and low sides
5. pressurize the system and check for leaks (this is why you started this in
the first place)
6. locate and seal any system leaks
7. purge the system with nitrogen
8. using the proper equipment, re-charge the system to the requirements
listed on the specifications label
9. If you're lucky and no corrosion or scale from your soldering operation
becomes lodged in the capillary tubes, the unit will probably cool again...
but for how long?
10. There is no warranty for the work you just had done, while you get a 2
year warranty with a new unit.
• You need a federal license to handle refrigerants (especially R-12 and R-22)
• It is a federal offense to knowingly
release refrigerants containing CFCs of HCFCs into the atmosphere, carrying a $10,000 fine per occurrence!
The above is the reason that the major RV air conditioner manufacturers no longer support this methodology. Most RV techs no longer have the equipment, training, skills and licensing to do the job properly
. I have an ARI Universal refrigerant license, but still wouldn't apply the above process on any
RV air conditioner............but if you feel that you have the expertise and qualifications....GO FOR IT........YMMV!!