View Full Version : Resi Tech Entering Refrigeration
Hello all, 1 Year Resi tech switching to commercial HVAC & refrigeration. Will be doing ice machines, walk-ins, supermarkets, etc.
My questions are about gauges and refrigerant/oil combinations. How many sets of gauges will I need to get started.
I have 1 set of R-22 gauges, w/low loss hoses
Getting 1 set 410A, w/low loss hoses.
What refrigerants can i expect to run into? Why are they used in those applications? I know the shop stocks 401, 409, 410, 404a, 134a, 22, 410a, 502, not sure what else.
Does anyone have a chart cross references refrigerants, their applications, and possible/suitable oils?
What can I use 1 set of gauges on, and when do I need a special set for a certain refrigerant? I know 410a w/POE requires it's own gauges to avoid contamination, but that's all A/C stuff.
I was told to get hose sets without low loss fittings, and to get long 5' or 6' hoses for market work.
Any other tips or suggestions guys?
Sorry for all the questions, but I'm a little overwhelmed and trying to gear up.
Thanks!
TR23
k-fridge
03-29-2007, 09:48 PM
You can use your "R-22" gauges for refer systems that don't use HFC refrigerants. It is best to have a separate set for systems with POE oil to avoid cross contamination. In reality this is not a huge problem, but by the book you should use separate gauges.
I never buy the hoses with the low loss fittings built on, I buy an add on low loss fitting and use it on the high side only when I'm connected to a schrader valve. Otherwise they just restrict flow and slow down evacuation/recovery time. And these things tend to give alot of trouble, better to replace just the fitting than the entire hose.
You'll need a 4 way valve wrench for king valves and adjusting some controls.
k-fridge
03-29-2007, 09:53 PM
Here's a little homework fer ya. :D
http://refrigerants.dupont.com/Suva/en_US/index.html
MikeySq
03-29-2007, 10:01 PM
put a P/T chart in your wallet
gather ice machine handbooks on the brands you work on
Tech Rob
04-02-2007, 12:21 AM
You may want to invest in a good set of "quickies". That is, basically, two gauges with no manifold, and 2-3' hoses w/ low loss fittings. When you're dealing with critically charged equipment, you definitely don't want to be using 6' hoses just for troubleshooting and getting an idea of what the system is doing at the moment.
A refrigerant scale is an irrefutable must. As is a micron gauge.
As for the refrigerants you'll encounter, it's a pretty safe bet your daily encounters will be by and large with 22, 404a, 134a, and 507. Depending on the age of the equipment you're working on , 12 and 502 may still be in there somewhere, but the majority of larger racks and boxes have long since been converted/replaced.
Refrigeration has it's own set of challenges just like A/C... Just the other day I was called out to work on a line cooler/reach-in, and I was faced with a reciever clearly stamped R-22, a compressor marked R-12, and an expansion valve with a bright orange power head labeled R-404a. Now tell me, what am I supposed to make of this?! LOL
I ended up dumping the charge completely and "picked" 404a
Anyhow, best of luck!
Thanks for all the tips guys, I appreciate the help, and would love any more!
hillbilly tech
04-02-2007, 09:23 PM
If ya don't already have knee pads get ya some,a scale,dial in refrigerant in small systems that are self contained when ya can,hold on tight its a ruff ride,takes years to be a pro and a lot of hard knocks at least in my case was this way.I love this stuff,but it is long hours,hard on family time and events,you truely have to like this stuff or it'll run ya nucken futs.Oh thought ide add I'm still going threw the hard knocks and been at it six years,kinda getten numb from the knocks now and they don't hurt as bad.From what ive learned work hard and don't let up or give up for a mans gotta have a job,Ive wanted to throw my toolpouch in the ditch at least a 100 times but got over it.
Powered by vBulletin® Version 4.2.0 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.