Leak Checks and Pressure Tests

[ch4man]

I am using a Robinair 16600, and Big Blu soap bubbles. He used to work at the gas company selling fireplaces is what i was told, he is more there for sales than anything else, gets our restock for the vans, sometimes, handles vehicle maintenance, sometimes, if you fuss enough. Been trying to get the oil changed in my van for 7000 miles now...

I know my detector isn't the best and I would like another one, but we are required to purchase our own tools and barely make a living wage. The only things the company supplies are: van, torch, nitrogen regulator, recovery machine. I am the only person in our company that even owns a vacuum gage.

i'm sorry..

you need two new things, but i guess you know that.











( if you don't know, you need a h10g and a new job )

as i said , i'm sorry. i wish you good luck. you obviously care. you deserve a decent company and a decent comany deserves you

[jaypslugger]

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.

The ability of the unit to hold a vacuum does not guarantee that the unit is tight. Consider that even under a perfect vacuum (30" hg, 0 psia) the greatest pressure differential between inside the system and outside will be about 14.7 psia. This is equal to "0"psig. So using a vacuum for leak checking is equivalent to a leak check using "0" psig pressure. Absolutely agree with using system operating pressure to leak check.

[71CHOPS]

you're automatically assuming a leak....and that's possible. but it is equally possible that someone let the charge out. kids getting high, or pissed off perp.

I'd bet leak too.....BUT, there is always the chance there isn't one.

[northeastbeast]

H 10's are what we got on our trucks, things work great, ive had real good results with mine.
@jmsmars1 i have to agree with ch4man there are definitely companies who provide more than that, my truck had pretty much everything you could think of on it for tools, except basic stuff that i needed for school anyways. truck had recovery device, cylinders, leak detector, vac pump, two nitrogen tanks, torch, regulators, pump sprayers, digi scale, micron gauge,ect ..ect... my boss encourages us to buy certain proprietary tools and I always use the company card , its a write off for him anyways.

[hurtinhvac]

Sched 40 black pipe is rated to 125 psi.
Code mandates pressure tests on res. gas lines to be done at a minimum of 15 psi.

Soo..... What are you talking about?

Even our local gas co. would look at me as if I was crazy if I dumped even 10 PSI in. They test with lung power or a little bulb pump and straight tube water manometers, 10 " wc, 10 minutes.

[mason]

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?

[hurtinhvac]

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.

[jtrammel]

We have a municipality that requires us check our gas lines at 60psi!!!

The other ones require 14-20psi.

We have to hold 10psi for 10 minutes for the gas company to set the meter.

[energy star]

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.

How much 22 you dump in a 410 system.

[mason]

I forgot about the time part.

Varies from 30min-2hours.

The 60 psi place also requires 2 hours and they don't allow any CSST at all. Needless to say companies don't like working in that area.

[stugops]

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

[syndicated]

Cut the system open.
Isolate the condenser, lineset and evaporator and braze on schraeders and caps.

You'll find it.

[speedytom]

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?