wrench409
Well-known member
Can dye's be used to track down my home HVAC unit yearly loss (1 ~ 1.5 lbs)?
Are schrader valves for auto use the same for HVAC use?
Are schrader valves for auto use the same for HVAC use?
Tracing an R22 leak
- Thread starter wrench409
- Start date
ctfjr
Well-known member
That's a big loss. The easiest way I've found is to use an electronic leak detector. Even a really inexpensive one (check ebay for a used one) will find that sucker quickly. I've never been a big fan of dyes.
Lassen Forge
Well-known member
A pound a YEAR isn't all that big a leak, and if its in the wrong place, you won't see the dye... I would second getting a leak detector (**NOT** a flame detector if you're in your attic!) and find it that way.
My guess is it's a bad junction / union / schrader valve / compressor seal. And while yes, they're the same valve, you need to remove your refrigerant to replace it, then evacuate the system to then recharge it... unless you have all the equipment from Manifold gauges to the R22 capture system to the vacuum pump (and IIRC you can't vent R22, you have to recapture it) once you find the leak you may want to then call someone out to do the repair.
Just my 2 cents...
My guess is it's a bad junction / union / schrader valve / compressor seal. And while yes, they're the same valve, you need to remove your refrigerant to replace it, then evacuate the system to then recharge it... unless you have all the equipment from Manifold gauges to the R22 capture system to the vacuum pump (and IIRC you can't vent R22, you have to recapture it) once you find the leak you may want to then call someone out to do the repair.
Just my 2 cents...
Mike-
Member
Mix up soap and water in a spray bottle, look for signs of oil and spray there.
Also, I've had distributors test reclaimed freon as you bring it in, and they refuse to accept it if it has dye in it. That's because the wholesalers won't accept it, and one contractors return can taint a whole 100 pound jug of theirs. Oh, they'll charge you $10 a pound to "destroy" it by burning.
So stay away from dye.
All of the leaks that I've been able to find were found by hearing, seeing, or soap bubbles. In the past, I would separate and seal the three parts of the system (i.e. evap coil, condensing unit, line set) and solder in a valve and pressurize them to 150PSI. Then come back in a day or two and see which one lost pressure. Nowadays, customers don't want to go this route.
Newer units are going to be worse in this regard. Alot worse. Just found out about this on Friday. Buyer beware.
So stay away from dye.All of the leaks that I've been able to find were found by hearing, seeing, or soap bubbles. In the past, I would separate and seal the three parts of the system (i.e. evap coil, condensing unit, line set) and solder in a valve and pressurize them to 150PSI. Then come back in a day or two and see which one lost pressure. Nowadays, customers don't want to go this route.
Newer units are going to be worse in this regard. Alot worse. Just found out about this on Friday. Buyer beware.
LS6 Tommy
Well-known member
A halide leak detector won't work if it's not a CFC or HCFC.
If the leak is at the Schrader valve, that procedure is overkill. Just get a core removal/replacement tool. Good ones come with a thermometer for doing superheat calculations. Here's mine:
You more or less have to recover ALL refrigerants.
Tommy
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zmaxmotorsports
Well-known member
I normally start with loose shrader valves,a simple valve core tool is a priceless item in this business.
If its not a shrader valve I normally will pump the Freon back into the condenser then pressurize the rest of the system with around 300lbs of nitrogen and start listening,youll here the leak.
If its not a shrader valve I normally will pump the Freon back into the condenser then pressurize the rest of the system with around 300lbs of nitrogen and start listening,youll here the leak.
I normally start with loose shrader valves,a simple valve core tool is a priceless item in this business.
If its not a shrader valve I normally will pump the Freon back into the condenser then pressurize the rest of the system with around 300lbs of nitrogen and start listening,youll here the leak.
Yeah, this. Also, no matter the system, if there are hoses, some tiny amount of loss with occur through the hoses, no matter what, it's unavoidable as I was taught in A/C class.
truckman5000
Well-known member
- Joined
- Mar 11, 2008
- Messages
- 1,440
look for oil residue.
zmaxmotorsports
Well-known member
If you were within a couple hundred miles of Omaha id drive over and fix it for ya,Of course it would cost you a ride in the 09 Impala.
Not a 2009,the other 09!
Not a 2009,the other 09!
Thanks all.
I do have the tools to do the job - already did the schrader valves. But still get a tiny beep on the leak detector.
What's frustrating is having to add freon every year at the seasonal change. I've been all over this system with the detector and all I've seen is those schrader valve faint beeps. No oil seepage seen anywhere. I guess since I have two 30 lb bottles of R22 I can continue adding as needed.
No dyes were used in this repair.
I like that thermometer type schrader valve tool! Mine is just the basic one. I use a digital with probes.
I do have the tools to do the job - already did the schrader valves. But still get a tiny beep on the leak detector.
What's frustrating is having to add freon every year at the seasonal change. I've been all over this system with the detector and all I've seen is those schrader valve faint beeps. No oil seepage seen anywhere. I guess since I have two 30 lb bottles of R22 I can continue adding as needed.
No dyes were used in this repair.
I like that thermometer type schrader valve tool! Mine is just the basic one. I use a digital with probes.
Milton Shaw
Well-known member
- Joined
- Feb 11, 2011
- Messages
- 4,836
Make sure you check the caps on the service valves, they can leak slowly when cold or hot and not show up when the system is off and pressure is equal. Would not hurt to put some Teflon pipe dope on these threads. I am not talking about the schrader valves but the service valves for isolating the system. When operating the high side is very hot and the cold side is almost to freezing temp. There is a lot of metal expansion when these temps change.
zmaxmotorsports
Well-known member
Make sure those caps are tight.Im not a big fan of the electronic leak detectors,looking at them wrong or even breathing around them can set them off.
How old is the system? After Johnson Controls bought York I suddenly went from 1 or 2 warranty leaks to 100% (No exaggeration, 100% coil failure rate under warranty), the coils would only leak when the system was running and the coil was cold. I was taking coils I believed to be leaking out and putting them under a 300 psi nitrogen test in my shop and found they would hold pressure indefinitely. 
If I put the coil in a barrel of ice water it would start leaking from everywhere. Supposedly this is due to porous China made copper being used by the manufacturers. I stopped selling York but have experienced the exact same issue with several Frigidaire and Aspen coils.
It can make finding a leak difficult. I now disable the blower and run the system with my leak detector in the drain pan to detect this issue.
If I put the coil in a barrel of ice water it would start leaking from everywhere. Supposedly this is due to porous China made copper being used by the manufacturers. I stopped selling York but have experienced the exact same issue with several Frigidaire and Aspen coils.
It can make finding a leak difficult. I now disable the blower and run the system with my leak detector in the drain pan to detect this issue.
LS6 Tommy
Well-known member
zmaxmotorsports
Well-known member
I worked on a heat pump this morning,I think it was a tappan.
Anyway the guy had some guy come out last year who told him his A coil was bad so he changed it and recharged system,a couple of weeks later it was low again and he wanted to try changing some parts,Homeowner got smart and ran him off.
Anyway today he calls me up to look at it and sure as **** as soon as I walk up to the units behind the house neither was running so I walked in and kicked on the main floor stat to kick that unit on.
Then I walked back outside and threw the gauges on the unit that wasn't running and found it was bone dry.
The clown had slopped a bunch of goop on the threads of the service valve caps before screwing them on,but he had the valves seated all the way against the fittings instead of 1/8" down from seated.
so I cranked them down 1/8' put the caps back on and snugged them up really good and dumped the nitrogen in and let it sit for an hr before vacuuming it down and recharging it.
Why does it seem like these installers that want to moonlight on craigslist always go right to selling somebody an A coil rather than using common sense to try and troubleshoot things first?
Anyway the guy had some guy come out last year who told him his A coil was bad so he changed it and recharged system,a couple of weeks later it was low again and he wanted to try changing some parts,Homeowner got smart and ran him off.
Anyway today he calls me up to look at it and sure as **** as soon as I walk up to the units behind the house neither was running so I walked in and kicked on the main floor stat to kick that unit on.
Then I walked back outside and threw the gauges on the unit that wasn't running and found it was bone dry.
The clown had slopped a bunch of goop on the threads of the service valve caps before screwing them on,but he had the valves seated all the way against the fittings instead of 1/8" down from seated.
so I cranked them down 1/8' put the caps back on and snugged them up really good and dumped the nitrogen in and let it sit for an hr before vacuuming it down and recharging it.
Why does it seem like these installers that want to moonlight on craigslist always go right to selling somebody an A coil rather than using common sense to try and troubleshoot things first?
fastjohnny
Well-known member
I worked on a heat pump this morning,I think it was a tappan.
Anyway the guy had some guy come out last year who told him his A coil was bad so he changed it and recharged system,a couple of weeks later it was low again and he wanted to try changing some parts,Homeowner got smart and ran him off.
Anyway today he calls me up to look at it and sure as **** as soon as I walk up to the units behind the house neither was running so I walked in and kicked on the main floor stat to kick that unit on.
Then I walked back outside and threw the gauges on the unit that wasn't running and found it was bone dry.
The clown had slopped a bunch of goop on the threads of the service valve caps before screwing them on,but he had the valves seated all the way against the fittings instead of 1/8" down from seated.
so I cranked them down 1/8' put the caps back on and snugged them up really good and dumped the nitrogen in and let it sit for an hr before vacuuming it down and recharging it.
Why does it seem like these installers that want to moonlight on craigslist always go right to selling somebody an A coil rather than using common sense to try and troubleshoot things first?
Follow the money....upsell to the unsuspecting/uneducated customer
