Posted by Chris Severance on May 09, 19100 at 23:07:55: via: d37.as0.jcsn.mi.voyager.net or 216.93.120.47
In Reply to: Leak detector posted by MikeU on May 01, 19100 at 04:52:45:
I have a TIF 8800. It's mainly used for combustible gasses but it also detects halogenated refrigerants though the ratings do not list them as detectable. I don't mean to suggest this the detector for you but I have been testing houses for LP and Natural gas leaks. Some of the houses where there are leaks, the owners report that their systems have recently been tested and found clean by the power company, HVAC/pipe fitters, or LP gas companies. I don't know what their standards are or what they are doing wrong but me and my TIF find each and every leak and pinpoint the exact locations without fail. The possible reasons for my difference in success are:
1. I'm better at it (not likely, I only had mine a week, leak detectors are dead simple to use)
2. My unit is not worn out (not likely since the shops will pay for new tips on a regular basis)
3. I am more patient and check more carefully (but aren't they paid to do this?)
4. My standards are higher (possible because so far 100% of the 5 houses tested have 1 or more severe leaks such that odor can be smelled)
5. Their units are not adjustable for maximum sensitivity so small leaks go unnoticed. Maybe I have the Cadillac of detectors.
Chemical leak detectors are not well suited for MVAC use because high winds generated by the cooling fan during pressurized operation dilute, shift, and obsure gassing leaks leading to false alarms and non alarms. For small leaks it is critical to be within a few mm from the gassing area to get a reading and be certain of it's location. Many AC parts are blocked by other devices and often not practical to disassemble to test.
Another problem is that the a leaking system must be filled with some detectable gas to find the leaks then must be removed to repair the leaks.
Yet another problem is that all rubber fuel lines evaporate fuel through the tubing wall in high temperature conditions which sets off the detector. Both GM high pressure hard tubing and Chrysler low pressure soft tubing sweat the same way and the same amount.
I am purchasing a ultrasonic leak detector to see if that can sniff out my remaining leaks. As I read, an ultrasonic leak detector does not get fooled by fans, wind, distance, or stuff in the way. An ultrasonic leak detector is much more versatile in that it can detect smaller leaks, vacuum leaks, pressure leaks regardless of the gas used, liquid leaks, leaks from reasonable distances, and leaks in a non uniform environment (such as a compressor seal behind all the mechanics). When no pressure differential is available to generate the sound, a sonic generator can be placed inside of a supposedly sealed area and leaks can be found that way. Some ultrasonic detectors can be used to detect mechanical defects transmitted through hard objects.
Warren's detectors may be good but they are not cheap. The refrigerant TIF's 5xxx are available at JCWhitney and many are on sale for a pretty good discount if you get the right catalog. Also check out the selection at the Network Tool Wherehouse. I bought my TIF 5550A and TIF 8800 on Ebay but had I looked at NTW prices more carefully I would probably bought the 8800 new. It all depends on what you're searching for.
Note: The 8800 does not have a fan.