I believe the actual code, but if someone could cite this it would be great, is to test at 3 times the operating pressure, so in residential that would be roughly 21"wc unless otherwise required by your municipality. Haven't worked any where that uses less than 14psi.
Anybody have info on this?
I've pretty consistently heard 2.5 x working pressure.
Prime example today, went on a no cool call this morning, found the unit had about 5 psi of refrigerant left in it, R410a. I added about half a pound of 22 and run the nitrogen in as high as my regulator would let it, 165 psi. I searched for a leak for about an hour and a half and found nothing. went back to the condenser and gauges still said 165. Now after the talk I gave the customer why it was important to do a leak check for $xxx/hour, I had to go back and explain I could not find one, it must be small, recommended injecting dye. So from this I could determine:
1) Since the machine was practically empty, it must have a leak.
2) If it held 165 psi nitrogen for 90 minutes without budging, it must not leak at 165 psi
3) the unit held a 450 micron vacuum for 10 minutes, so based on number one that means nothing.
4) To properly check a 410 system for leaks, you have to be able to put at least as much pressure on it as it operates at.
If it were not for discovering the system empty, I would have said it had no leaks.
Good day to all.I am new to this site and would appreciate any help I can get. For the life of me I can't find the leak on a R410A system. I tried everthing, but no luck. The only thing left is dye. Any suggestions? stu
Cut the system open.
Isolate the condenser, lineset and evaporator and braze on schraeders and caps.
You'll find it.
I had a 410 package that leaked. Couple years old. I isolated and found no leaks. Was called a year later and was empty again. Unit was left to sit for half a day while I did other calls. Came back and was frustarated to see nothing moved.
I also have a leak detector TIF ZX9. Iv found it works really good on 22 not so good on 410. Anybody else have the same experience?