For solder style a/c condensers is it mandatory to use heat absorbing paste? the reason i ask is that i have always used it without question.Of course today being saturday the wholesalers are closed and i find myself with a two year old half used tube that looks good but I'm not sure.Anyhow i once had the pleasure(not really) of having to replace the valves on a condenser that had been overheated by someone elses crappy solder job.He didn't use paste and while i will use it i don't know if it's still good.Getting back to the crappy solder job this guy did't belive in evacuating the system either just filling it with nitrogen and opening high side condenser valve and pushing it out.He honestly looked at me like i was from another planet for using a vac pump.Guess i'm old school but ive never and i mean never had a joint leak.Im using a tubo torch not oxy/acet.Need this info quick please.
in a pinch. i remove the needle valve and wrap a wet sock around that "area". i always do the low side first and have had no problems. hope this helps!!
Wrap a wet rag around the valve body with the pin out.
Heat the pipe up a few inches before the connection, then hold the torch pointing away from the valve body at the joint. Good luck.
What's up with the note that was on new Goodmans for a while, telling you *not* to remove the shrader core when brazing???
You guys are right i forgot to mention pulling the shrader valve needle and I put a brass o-ringed cap on the portswhen done.The wet sock/rag idea is a keeper to.So the thermal paste is just a pice of mind thing or do you infact usually paste the line?I use oxy/acet torches at work instead of a turbo because its a hotter tighter flame and the piping around the joint seems to say cooler than the turbo torch.I work in a hospital on mostly reftigeration equipment that dosen't have this type of valve and i only get into cenral air units for familly.Soldering this close to a loaded valve seems to beg for a leak.When i cut out the valve on the unit that the guy over heated it also was a saturday.I swaged a small length of pipe drilled a hole in the center and soldered in a shradder valve on the low side like the old days.Thanks again for the replys.
[Edited by mac on 05-29-2004 at 02:24 PM]
I have had some paste that was old and not dry-ed out ( I believe that is the key) and it worked. I have the problem that here in the heat it drys out if the cap is off.
Always use a damp towel or something along those lines any ways.
i have never used that paste i have allways used the wet
rags but want to try the paste in tight places were wet rags seem to put out my torch flame
i always use the GOOP on the A COIL/PLENUM and especcially a CASED A COIL
the new goop is bla bla 2 and is clear like K-Y and over $8.00 a tube
recently, i sqeezed some of the goop in the wet sock...and well......ahhh nice... really, though, it worked great as it kept WET but not drippy and didnt fall off the valve body and "git in my business" (touch that goop on your braze stick or on your brazing spot and it is NOT like flux...at all.
no K-Y cracks...you jokers!!!
Ive been welding service valves tx valves reversing valves etc for 20 yrs and have always used a wet cloth rag. I have never used any kind of heat trapping paste ever and I have never damaged a valve either. I keep a bottle of water haNDY to pour on the rag if it is drying out as I'm welding. It can be done without the paste no problem but if you want an extra measure of safety then apply the paste
take a Rigid pipe wrench/big adjustable and chill it with a bucket of ice and water(just the jaw area).tighten it on the body and then wrap that with a damp rag,works great on sightglasses too or threaded areas where you have to torch copper in where you can't turn to install the piece.
I have used both wet rags and thermotrap equally for years
with good success with both. I probably use the thermotrap
more often as I don't have to hunt around for water (lazy aren't I?). With either option, I always aim the flame away from the component to be brazed in. It seems to work