Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

Line pressure question


  Email This Post



katomun
New User

Sep 21, 2015, 4:00 PM

Post #1 of 8 (1433 views)
Line pressure question Sign In

Hi everyone, I have a '95 Mazda 626 2.0. Originally, low side was reading about 20- 25 psi and high side read very high about 195-200. I replaced the expansion valve and dryer. Tried blowing out the high side lines and the evaporator with an air nozzle. Replaced all of the o rings. Now, after recharging with a 12 oz can, the pressure now reads low side about 60 and high side about 100. Did the compressor just go bad? Thanks.


Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Sep 21, 2015, 5:24 PM

Post #2 of 8 (1428 views)
Re: Line pressure question Sign In

The pressures originally looked good. Was it not cooling?

Did you evacuate the system before adding refrigerant? System capacity is 1.54 lbs.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.

(This post was edited by Discretesignals on Sep 21, 2015, 5:27 PM)


katomun
New User

Sep 21, 2015, 6:23 PM

Post #3 of 8 (1421 views)
Re: Line pressure question Sign In

It was blowing warmer than usual, It's been several months since I worked on my car but if I remembered correctly, low side was actually about 15 and high about 140ish or so. I added a can and low side stayed the same and high side shot up to 200. Checked online diagnostics and came up with a bad expansion valve. I evacuated the system for about 45 minutes with a vacuum pump and let it sit for a while after replacing. No leaks. The pressure now reads low side about 60 and high side about 100.


(This post was edited by katomun on Sep 21, 2015, 6:38 PM)


Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Sep 21, 2015, 6:37 PM

Post #4 of 8 (1415 views)
Re: Line pressure question Sign In

The high side is going to go higher with more refrigerant in the system, but 200 isn't unusually high.

The system has to have the proper weight refrigerant in it to diagnose it properly.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.


katomun
New User

Sep 21, 2015, 6:49 PM

Post #5 of 8 (1410 views)
Re: Line pressure question Sign In


In Reply To
The high side is going to go higher with more refrigerant in the system, but 200 isn't unusually high.

The system has to have the proper weight refrigerant in it to diagnose it properly.


My previous post edited. Please re read. Had to think twice what I did originally. Adding refrigerant to spec wouldn't help because low side now reads 90 after evacuating and 12 oz freon after replacing valve.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Sep 21, 2015, 6:50 PM

Post #6 of 8 (1409 views)
Re: Line pressure question Sign In

I don't know what you did but you turned a good low pressure reading into a bad one. You've got signs of a bad compressor now.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Sep 21, 2015, 6:58 PM

Post #7 of 8 (1406 views)
Re: Line pressure question Sign In

This sounds like a mess and you should start over. You should have someone with an ac recovery machine recover what you have in it and then recharge it to the correct weight using a cylinder and scale. Then see what your readings are.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.

(This post was edited by Discretesignals on Sep 21, 2015, 6:59 PM)


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Sep 21, 2015, 9:24 PM

Post #8 of 8 (1394 views)
Re: Line pressure question Sign In

Here we go. OP, did you blow lots of oil out of system too with those tricks? Charge has to be on target if you have to start over from a full vacuum. Said right away pressures seemed fine so was/is something else now random blasting in refrigerant probably caused a problem and original problem till exists.


High side pressure look for 2.5X the air temp (F) going in thru grille at 1,500 RPM or around there, fans running.


1.54 lbs of charge is going to be tough to get spot on and probably way off and need help with equipment. Too bad IMO that you messed with it,


T







  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap