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View Full Version : Removing sweat on Filter Dryer dangers?







mooka
22-09-2007, 01:08 AM
Is there any danger in removing a sweat on Filter dryer that has been in service? I will decant the refrigerant first of course, and wrap the filter dryer in wet rags when I sweat it on, but should I looking out for anything else while doing this?

Thanks

BigJon3475
22-09-2007, 02:35 AM
Don't sweat it out - cut it out.

taz24
22-09-2007, 10:49 AM
Is there any danger in removing a sweat on Filter dryer that has been in service? I will decant the refrigerant first of course, and wrap the filter dryer in wet rags when I sweat it on, but should I looking out for anything else while doing this?

Thanks

If you sweat it out then you must be careful of any oil that is in the drier. As you break the joint with the flame on it if there is oil in the drier it can and does ignite and flare up for a second.(quite like a flash fire).
If you are not wearing the correct PPE or if you are not expecting it it can catch you and there is a slight risk of you getting burnt.

As the previous poster stated if you have the space cut it out if you want to heat it out just be careful.

Cheers taz.

Argus
22-09-2007, 11:12 AM
Don't sweat it out - cut it out.

Asolutely! Big J's right.

Even after withdrawing the working charge, the drier core will still contain traces of refrigerant and oil that can ignite.
As well as the obvious personal risk, you'll also fill the system with unwanted krud as it smokes away when you are burning.

Additionally, any moisture that it contains in the cores can be evaporated back into the system and you're back to where you started.....

.

mooka
22-09-2007, 10:17 PM
Thanks for the quick response all. I guess cutting is the only way to go, have to find myself a tube expander or a couple couplings. Mabye I should add a sight glass while I am at it.
Many thanks again
Tim

Andy W
23-09-2007, 08:13 PM
What advice does your boss or the person who trained you have? It is always safer to cut one side of the drier just in case the filter is blocked, also regarding a sight glass, I presume it is an expansion valve system and not a capillary.

mooka
25-09-2007, 01:31 AM
It is a capillary system, and I have been getting into the habit of sweating on a sight glass. The person who trained me is long gone, moved out west with the oil boom (Alberta, Canada)

BigJon3475
25-09-2007, 02:09 AM
Capillary tube systems have to be charged correctly to get the full potential out of the system you are charging to superheat and sub cooling correct? Not just the sight glass.

Andy W
25-09-2007, 07:56 AM
Dont fit a sight glass to a capillary system.

mooka
26-09-2007, 11:09 AM
Superheat and subcooling specs, I follow and usually no call backs. Once I had a "pulsing" discharge line right where the cap tube starts, I added a couple ounces, the pulsing stops. Still not sure on why or what caused it, but its cooling quite nice. Andy W, why not fit a sight glass to a capillary system? Its just nice to see if there are any bubbles in the system, a quick check.

Tony
26-09-2007, 09:27 PM
What refrigerant is in on? Beware brazing if it is R600a, which a lot of domestics use now!!!

mooka
07-10-2007, 01:58 AM
Sorry Tony, I should have included that the system was charged with R-22.
Thanks

The MG Pony
08-10-2007, 08:25 PM
fitting a sight glass on a captub system is a waste, ie totaly pointles as even correctly charged you may or may not see bubles.

A cap tube system is a critical charge type, the ONLY proper way to do it is by Super heat and sub cooling, there are tricks that will get you ruffely into the right area fast, then you may fine tune it.

One such trick is to stop the evap fan then charge it till it frosts just 6 inches from the suction port on the compressor, start the fan up then fine tune it. Having a sight glass through this is useles fiy.

I hate to say this but the person poorly trained you, may I sugest you read all the sporland PDFs this will greatly assist you in allot of proper methodology and provide valuable info for you, along with the great team on this forum, they havebeen a great help for my self and as you've seen, many others!

By usuing super heat and sub cooling you can even charge a TXV system with out a sight glass, the sight glass is more usefull on SAE-Flare systems to help watch for moisture more then any thing, and under stable box temps it will help you determin if you have a bad leak, nothing more then that though, I have been working to eliminate the sight glass out off all systems I produce due to it being a non critical part IMO.

kelvin kline
08-10-2007, 08:38 PM
Speaking as a person who has experienced a drier explosion..i would say, without exception, cut the body of the drier to make certain that the body of the drier is void of gas.a simple hacksaw cut will put your mind at rest.

I was sweating a dries out and was absolutley sure that the system was clear....1 mili second later a blast and a trip to the hospital to pick out the silicagel beads from my eyeballs and dress the cuts.i still have the remains of the drier as a keepsake...it looks like an autumn leaf.
several meetings with the health and safety executive...don`t take chances with your health.

BigJon3475
09-10-2007, 04:01 AM
I would have to recommend against cutting it out with a hacksaw also since you are subjecting the lines to the shavings from using a saw. Tubing cutters IMO are the best choice.

kelvin kline
09-10-2007, 08:51 AM
tube cutters are fine for copper, but not on steel.If you cut the steel line whilst it is pointing downwards, the "shavings" will fall away from the open end of the pipe.This is of course, if you cut it out as opposed to sweating it out.The hacksaw cut mentioned was meant to be across the body of the drier to make sure that all gas had been removed.

Personally, I scratch and break the capillary to leave a nice fully open tube, then polish the liquid line for a couple of inches before the drier then cut it out, and debur it.This takes the drier and any oil/gas, residue out without smoke and fumes.Think H&S.

BigJon3475
09-10-2007, 05:09 PM
tube cutters are fine for copper, but not on steel.If you cut the steel line whilst it is pointing downwards, the "shavings" will fall away from the open end of the pipe.This is of course, if you cut it out as opposed to sweating it out.The hacksaw cut mentioned was meant to be across the body of the drier to make sure that all gas had been removed.

Personally, I scratch and break the capillary to leave a nice fully open tube, then polish the liquid line for a couple of inches before the drier then cut it out, and debur it.This takes the drier and any oil/gas, residue out without smoke and fumes.Think H&S.


okay sorry I must misread it was for steel. Not much else you can do with that but cut it out.