leak search in large refrigeration pipe system

[Tommy knocker]

I don't see the need of electronic leak detection for large tubing runs. If you have good installation practices with trained installers, why should there be leaks in the first place? If you are sweating/brazing 2" & 3" copper, with sil fas, using a n2 purge, why would you need an electronic leak detector? You typically should not have leaks with a copper tubing installation. You could visually inspect the sweat joints too. The armerflex should be installed after the piping system has be approved, shouldn't it? Leak detectors are most valuable when used tracking down leaks on systems with many connections, valves, components, etc. already in service. Right?

Agreed. The ELD will typically stay in the truck until I'm sure I have a leak that's not jumping out at me, on new set ups anyway. I will grab it before bubbles however. No particular reason it's just what I do. ELD to get me in the area and bubbles to pinpoint.

[coldseeker2013]

Good evening to everyone.
I have spent the last couple of days getting everything needed for the job: N2 cylinders, new sensors for the ELD, and a pair of bottles of a leak detection bubbling solution recommended by a counter salesman. I also assembled a mobile scaffold since most of the pipes are about 20 feet above the floor level. When I thought I was ready to go, the first thing I did was blow some N2 through the first pipe, and what I discovered was not very pleasant: lot of debris came through the other end of the pipe. To my understanding, this means that whoever did the welding, did not use an inert gas while brazing. I suggested to the project manager that pipes should be cleaned before looking for leaks. I have used N2 + R-141 as flushing agent in some much smaller pipe systems, but, would it be equally effective in this large volume piping?

[coolerik]

That sucks man, but you would need a crap load of flush to flush out lines of that size and length, if it were me I would blow out what I can with nitro and you should be fine, just document it so whoever is doing startup is aware of it, and they may be changing oil, drier cores and cleaning txv screens over the first bit of run time...I would say flushin is not a realistic option. What type of system is this anyway?

[coldseeker2013]

Good evening.
These large pipes belong to the refrigeration system of a large walk-in freezer being installed in a supermarket. The equipment has not being brought in yet, but I read in the specs that it will work with R-404a. I would like to just blow the pipes with nitrogen and leave the messy work you just described for someone else, but, do you know of any other better flushing procedure that I could use besides Nitro+solvent ?

[jpsmith1cm]

The system's filter-driers will catch the debris upon startup.

Not optimum, but it happens on almost every supermarket install I've been around.