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 03-19-2014, 09:23 PM   #61
Member
 
Join Date: Nov 2012
Posts: 60
Rewards Points: 75
Default

3 ton evap 2 ton compressor


I check everything again using analog gauges. MY sman 4 was a little off but only by 7 psiG. Still -25 subcool and 15 super-heat. I have a 3 ton fan now and a 3 ton piston. I am getting 30+ delta T. I think I am going to put a schader valve in the liquid line in the attic and check subcool from there tomorrow. Something just doesn't make sense! Somehow or another I have defied physics.

subcool is offline   Reply With Quote
Old 03-27-2014, 01:18 PM   #62
Member
 
Join Date: Nov 2012
Posts: 60
Rewards Points: 75
Default

3 ton evap 2 ton compressor


ok added a service ports and a sight glass on both vapor and liquid line in attic. Numbers look good up there. Here is what I have:
outside unit in AC mode
outside is 40 degrees inside is 77DB
with fan cover 1/4
True suction 45 psig
Vapor 44.5 and 52.3 degres
Liquid 112.8 and 56 degrees
That gives me a subcool of 12.6 and a super heat of 29.4
A little under charged but looking good/ normal.

The inside numbers looked about the same temp was off by 1, but that was a different temp probe.

In HEAT mode outside unit:
outside temp now about 46 and 72 inside
true suction 55 and 52 degrees gives super heat of 22
vapor 282 and 164.5
liquid 80 psig and 96 degrees give no subcool or 50 degrees of super heat


Inside numbers
Ready for this?

vapor 280 and 162
liquid 300 and 116 degrees giving a subcool of about 12 degrees


I am dropping 220 from the output of the condenser to the service port outside. I checked the temp drop across the LLFD and it was almost 0.0 remember it is new. How in the heck could I drop that much pressure? Then in AC mode it works perfect! YES it is a biflow LLFD.
subcool is offline   Reply With Quote
Old 03-27-2014, 04:27 PM   #63
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,580
Rewards Points: 2,840
Default

3 ton evap 2 ton compressor


I forget. is this a Carrier condense/heat pump? If so, many of them have the outdoor piston in the liquid line service valve. So when you take a liquid line pressure outside, its after the metering device, and will not be the true liquid line pressure.

A LLFD can be restricted, and not have a temp difference across it.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Old 03-27-2014, 06:36 PM   #64
Member
 
Join Date: Nov 2012
Posts: 60
Rewards Points: 75
Default

3 ton evap 2 ton compressor


Yes this is a carrier. I added a service port before the LLFD changed the LLFD and the same think. On the incoming side of the LLFD I am getting 200 pgiG and st the service port im getting 45. How does that piston come out? I see frost right there, but I would think I should since it is changing states there.

I don't ever remember having this problem before, I have checked this is the winter lots of times. So what you are saying is take the reading before the filter? How would you ever take that reading if you did not put in another port?

Last edited by subcool; 03-27-2014 at 06:38 PM.
subcool is offline   Reply With Quote
Old 03-27-2014, 07:24 PM   #65
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,580
Rewards Points: 2,840
Default

3 ton evap 2 ton compressor


Another post is the only way.

Carrier, does not expect you to take a liquid line reading in heat mode.

__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   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
3.5ton evap with 4 ton compressor wetbar HVAC 1 06-15-2013 04:41 PM
15 degree split, scroll compressor is hot!! bobinphx HVAC 1 06-05-2013 04:30 AM
Help assembling compressor jfhspike Tools 5 03-27-2011 10:07 AM
Air compressor and framing nailer for DIY ADKstorm Tools 20 11-11-2010 07:38 AM
New Compressor - Wrong Charge? shayneb HVAC 4 08-23-2008 08:13 AM




Top of Page | View New Posts

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