Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 06-29-2009, 07:09 PM   #1
Newbie
 
Join Date: Jun 2009
Posts: 5
Share |
Default

high head pressure low suction


I just wanted to pick every ones brain i could. I am working on trane condensor and have high head pressure and low suction pressure. It was 90+ out today and I dumped r-22 into the system and no matter what I did I could not get the suction line to sweat and the superheat never dropped below about 20 degrees. my head pressure was around 285 and the suction around 55. I am thinking it may have a missing piston or the compressor. I would love some feedback

tcbaker72 is offline   Reply With Quote
Old 06-29-2009, 07:19 PM   #2
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Default

high head pressure low suction


Need more info. Tonnage of unit. How much refrigerant did you put in?
Why do you think you need a sweaty suction line? That depends solely on the the dew point of the air.

Why do you think its the compressor. Are you a tech?

__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 06-29-2009, 07:31 PM   #3
Newbie
 
Join Date: Jun 2009
Posts: 5
Default

high head pressure low suction


yes i am a tech and the dew point does matter. I was working on another model that was the exact same and was able to get the suction line to sweat. the evaporator is clean aswell as the filters. the sytem is a three ton unit with matching evap. the thing i was concerned about was the superheat. 8-10 is standard and the suction pressure should have been around 60-65 according to the manufacturers paper work with a head pressure of 270-275.
tcbaker72 is offline   Reply With Quote
Old 06-29-2009, 08:23 PM   #4
GC/Master Plumber/Mech
 
Join Date: Feb 2009
Location: Hays, KS
Posts: 1,467
Default

high head pressure low suction


Have you washed out the condenser coils?
Plumber101 is offline   Reply With Quote
Old 06-29-2009, 08:25 PM   #5
Newbie
 
Join Date: Jun 2009
Posts: 5
Default

high head pressure low suction


no i did not but that was only because they looked clean
tcbaker72 is offline   Reply With Quote
Old 06-29-2009, 08:30 PM   #6
GC/Master Plumber/Mech
 
Join Date: Feb 2009
Location: Hays, KS
Posts: 1,467
Default

high head pressure low suction


Looks and Is clean are two different things.

Had one yesterday pushing 300 hi washed coils brought it down to 225.

There are many things that push up hi pressure but the most common that I see is dirty condenser coil and a high heat load

Wash it and see what happens..what is 10 mins
Plumber101 is offline   Reply With Quote
Old 06-29-2009, 08:32 PM   #7
Newbie
 
Join Date: Jun 2009
Posts: 5
Default

high head pressure low suction


thanks for the advice. iwill try it tomorrow
tcbaker72 is offline   Reply With Quote
Old 06-29-2009, 08:38 PM   #8
Too old to argue with you
 
Join Date: Jun 2009
Posts: 6
Default

high head pressure low suction


The first rule I learned 30 something years ago. If the unit runs, grab a hose and clean the condenser. You would be amazed by the amount of customers who sweep the junk off the fins and try to tell you that they cleaned it.
30yrhvactech is offline   Reply With Quote
Old 06-29-2009, 08:52 PM   #9
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Default

high head pressure low suction


55psig and 285 head after you added gas... by this i am assuming you mean enough so that it should have affected the back press.

With that high a super heat and and hi head that is probably a partial restriction.

Dirty condenser would give you much higher lo side.

How was the amp draw?
__________________
Just slow, not stupid.

Last edited by hvaclover; 06-30-2009 at 08:10 AM.
hvaclover is offline   Reply With Quote
Old 06-30-2009, 05:52 AM   #10
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 24,401
Default

high head pressure low suction


Why do so many get hung up on only looking at SH on a fixed metering device system.

Always chck your SH and SC on both fixed metering device systems, and TXV systems.

It will lead you to the problem.
beenthere is offline   Reply With Quote
Old 07-11-2009, 10:50 PM   #11
Newbie
 
Join Date: Jul 2009
Posts: 29
Default

high head pressure low suction


Quote:
Originally Posted by hvaclover View Post
55psig and 285 head after you added gas... by this i am assuming you mean enough so that it should have affected the back press.

With that high a super heat and and hi head that is probably a partial restriction.

Dirty condenser would give you much higher lo side.

How was the amp draw?
doesen't take much to plug that little piston i've taken chips of valves , solder balls , & debris from poor brazing practices , easy to check & repair.........Jack
psilliman001 is offline   Reply With Quote
Old 07-12-2009, 09:00 AM   #12
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Default

high head pressure low suction


high head pressure low suction..

in my day we would call that the perfect date!
__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 07-12-2009, 09:10 AM   #13
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Default

high head pressure low suction


Quote:
Originally Posted by psilliman001 View Post
doesen't take much to plug that little piston i've taken chips of valves , solder balls , & debris from poor brazing practices , easy to check & repair.........Jack

Man that ones hits a nerve!

I totally agree with you, a filter drier in near the evap would eliminate most of that.

__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
I was told water pressure too high - bunk or truth? vsheetz Plumbing 5 04-23-2009 08:01 AM
too High boiler pressure beacu Plumbing 2 10-18-2008 11:52 AM
Pool Motor Wiring Assistance tazmajazz Electrical 18 05-16-2008 10:42 PM
High pressure bjr23 Plumbing 1 03-27-2007 07:24 PM
High pressure in water line atlfiveo Plumbing 5 02-06-2007 09:04 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.