Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site bsdpkh.UUCP Path: utzoo!watmath!clyde!bonnie!akgua!akguc!codas!bsdpkh!heffner From: heffner@bsdpkh.UUCP (Paul K Heffner) Newsgroups: net.auto.tech Subject: Re: air conditioning advice Message-ID: <116@bsdpkh.UUCP> Date: Thu, 24-Oct-85 22:44:16 EDT Article-I.D.: bsdpkh.116 Posted: Thu Oct 24 22:44:16 1985 Date-Received: Sat, 26-Oct-85 04:29:29 EDT References: <1735@akgua.UUCP> <132@inuxa.UUCP> <393@cylixd.UUCP> <494@ttrdc.UUCP> <29ae0a4e.3b@apollo.uucp> Organization: AT&T-IS (SDSS), Orlando Fl. Lines: 48 > >I have also heard of a special propane torch head which has an attachment > >for a hose, used for the purpose of sniffing freon..... > > Aieeee!! This is something you don't want to do! The combustion products > from freon are quite toxic. All that fluorinated and chlorinated stuff is > bad news when you burn it. > My father runs an A/C-Refrigeration repair buisness (1-man) and I have been literally been fixing the stuff as long as memory serves. (It broke the old boy's heart when I became a bit flipper...) I've been following the A/C repair discussions with interest and I hope I can add some useful input. Scott Wilde was technically correct regarding the burning of F-12 in Propane as it forms Phosgene gas which is rather noxious. The leak detector device under discussion however, is not likely to produce enough (given a reasonably small freon leak as the one under discussion) to do much more than make you sneeze. As an aside, it has only been within the last decade that propane torches have taken off for general refrigeration repair use. Before that it was always acetyline torches for soldering/leak detecting which never seemed to produce any noticable smell. Regarding the use dye to find the leak, DuPont was marketing F-12 with an additive called (I believe) Dyetel. We found this far more desirable than a dye additive as the additive was suspected to corrode the copper fittings. Actually the dyes very rarely ever were of use as the freon has a tendency (spraying out under high pressure) to just dye up the whole general area and leave a mess. We had lots of luck, however, with the simplest and cheapest detector of all: Bubbles!! (Childrens soap bubbles) Bring the system up to a reasonable pressure (50-100 psi if you have gauges) and use a small brush to soak the stuff on all the joints you suspect. Even the smallest leak will produce noticable bubbles. Use a small mirror to peek behind the joints as the bubbles will appear usually at one side of the joint. Since you have been adding freon for years and not adding any oil, there's a good chance the shaft seal of the compressor is your (primary) leak as the system oil recirculates through the system and will escape along with a leak. Refrigeration oils are specially formulated for low wax and moisture content. A good mechanic will evacuate the system to remove any air which might have migrated into the system. An extremely low vacuum on your system causes any moisture to vaporize and be drawn out. He can also ( If well equipped) replace the oil (can require a special pump) Sorry to ramble on so, hope this helps.... Paul Heffner {ihnp4,akgua}!bsdpkh!heffner