View Full Version : charging liquid
blewbyu2
08-10-2009, 09:17 PM
Trane RTAA 200ton just short of charge 50 lbs. I charged in vapor just like the manual says. Used heat gun to boost pressure on the tank,but still slow. Now the question, can I trickle in liquid without doing damage to the screw compressor? I did fix the leak, the relief valve blew because of 3 fan failures.
always looking
08-10-2009, 09:53 PM
The factory charge on those units are wrong. If you weighed the charge and are 50 lbs shy of the nameplate you should be good. Those units operate the best when sucooling is 15 degrees.
drivewizard
08-10-2009, 10:11 PM
You should have a service valve at the outlet of EXV, or inlet to evap. Feel free to dump liquid in there as fast as you like.
You can charge liquid at the suction service valve also, using common sense. Don't hook up a 125# cylinder with a 3/8 hose and run full open.
Although it may take it, I wouldn't try it.
blewbyu2
08-11-2009, 07:24 AM
You should have a service valve at the outlet of EXV, or inlet to evap. Feel free to dump liquid in there as fast as you like.
You can charge liquid at the suction service valve also, using common sense. Don't hook up a 125# cylinder with a 3/8 hose and run full open.
Although it may take it, I wouldn't try it.
I was going to charge at the valves after the exv but they were so rusted that I figured I'd be asking for trouble if I'd even touch them with a wrench. I just vapor charged since I had two other chillers down. Thanks for the info.
jemawalton
08-11-2009, 07:14 PM
The factory charge on those units are wrong. If you weighed the charge and are 50 lbs shy of the nameplate you should be good. Those units operate the best when sucooling is 15 degrees.
I don't remember the 200 being a problem. I thought it was only 240 and up and only mfg before June '96. In those cases the second circuit was 100tons and the charge should be 130lbs R-22. Nameplate said 180lbs.
jayguy
08-11-2009, 07:16 PM
You should have a service valve at the outlet of EXV, or inlet to evap. Feel free to dump liquid in there as fast as you like.
You can charge liquid at the suction service valve also, using common sense. Don't hook up a 125# cylinder with a 3/8 hose and run full open.
Although it may take it, I wouldn't try it.
if you pull the cores out it will go faster...they can take it easy.
txhvac
08-11-2009, 09:19 PM
I was going to charge at the valves after the exv but they were so rusted that I figured I'd be asking for trouble if I'd even touch them with a wrench. I just vapor charged since I had two other chillers down. Thanks for the info.
Back up wrenches come in handy there, I'd be careful charging there easy overcharge, as long as you don't do what DriveWizard said you'll be alright.
Octopus
08-22-2009, 01:23 PM
When ever a unit is large enough and I don't want to load liquid I break out the recovery machine and pull vapor out of the jug and into the unit makes charging much faster! Or you could use cap tube charger eh they suck!
ChillerWisperer
08-22-2009, 01:49 PM
When ever a unit is large enough and I don't want to load liquid I break out the recovery machine and pull vapor out of the jug and into the unit makes charging much faster! Or you could use cap tube charger eh they suck!
Try that on an RTAA and you'll be there a week. Would work well on resi and small commercial...completely different animal.
ryan1088
08-22-2009, 02:18 PM
When ever a unit is large enough and I don't want to load liquid I break out the recovery machine and pull vapor out of the jug and into the unit makes charging much faster! Or you could use cap tube charger eh they suck!
assuming we are talking about a large unit, why pump vapor? why not pump in liquid? pumps much faster.
Octopus
08-22-2009, 06:32 PM
Do you know what happends when you dump liquid refrigerant into a chiller barrel that has a vac? OUCH! So the first 30-50psi better be vapor.
Dallas Duster
08-22-2009, 06:51 PM
Does a recovery machine condense vapor into liquid?
Octopus
08-22-2009, 07:03 PM
It depends on how much refrigerant you are moving normally no, recovery machine will knock if it's valves are open all of the way if you start to move liquid. The recovery machine pulls vapor from the top of the recovery cylinder and puts it back into the chiller. Think push pull without the pull.
heavymetaldad
08-22-2009, 07:50 PM
Do you know what happends when you dump liquid refrigerant into a chiller barrel that has a vac? OUCH! So the first 30-50psi better be vapor.
and if you're dealing with r11,113,114,123 then what? eek 2
Octopus
08-22-2009, 07:53 PM
Eh low pressure ummmmmm boiler or something you guys use right? I donno........... Can you educate us?
Wait a min dry ice right........ Can't remember...
heavymetaldad
08-22-2009, 07:56 PM
need an address to emails or get to pro for pm. :D
Powered by vBulletin® Version 4.2.0 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.