IPD sale Volvo Parts
XeMODeX - Experts in Volvo Electronics My Swedish Parts ad - genuine Volvo parts
Did you know? 🤔
Logged in users can get email notification of topic replies Log in or register (free).
Amazon Link Buy your stuff using this and it helps MVS!

A/C pressures

Help, Advice and DIY Tutorials on Volvo's extremely popular car line -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, 850 R, 850 T5-R, 850 T5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

User avatar
greg850r
Posts: 190
Joined: Thu May 03, 2012 5:06 pm
Year and Model: a long list
Location: Mo
Has thanked: 1 time
Been thanked: 4 times
United States of America
greg850r

A/C pressures

Post by greg850r » Tue Jul 23, 2019 12:58 pm

Hi all,

I have a 96 850 T. I charged the A/C and it had cold air for a day or two but leaked out and the compressor stopped engaging. The smell in the interior points to a bad evaporator, but it did hold 28 inches of vacuum for 30 minutes before I filled it the first time.
I had a little freon left in a can from charging another car and I thought I'd plug it onto this one to get the the compressor to run and see where it was at pressure wise. The gauge said 35lbs, which should have been just enough to get the compressor to come on but it won't unless I jump the plug to the low side switch. When I do the gauge immediately goes to zero. I'm thinking orfice is clogged. Thoughts anyone?


05 Cross Country wagon
99 C70 Convertible
96 850R wagon
96 850T wagon
96 850 GLT 5spd N/A sedan
97 850R 5spd sedan
66 GTO 421SD 4spd
67 GTO 455 T400
02 Powerstroke 4x4
85 Yota 4x4
24' 454 Challenger
07 Softail Custom
02 Sportster Custom
Parts cars not included

Ozark Lee
MVS Moderator
Posts: 14791
Joined: Thu Sep 07, 2006 8:24 am
Year and Model: Many Volvos
Location: USA Midwest
Has thanked: 4 times
Been thanked: 45 times
United States of America
Ozark Lee

Re: A/C pressures

Post by Ozark Lee » Tue Jul 23, 2019 9:29 pm

The kick out pressure is around 28 to 30 PSI but the kick on pressure is higher than that. Everything says that you have a leak since it was charged and now you only have 35 PSI static pressure. On a moderately hot day the static pressure would be at or above 100 PSI on a fully charged system - it is totally dependent on the underhood temperature at the time of the reading.

I think you know what you have going on, and it is a PITA. It is about a 95% chance that you have a bad evaporator. If you follow the guides in the repair database it is a doable job by a mere mortal but figure on a couple of uninterrupted days to do it.

...Lee


'94 850 N/A 5 speed
'96 Platinum Edition Turbo
Previous:
1999 V70XC - Nautic Blue - Totaled while parked.
1999 V70XC - RIP - Wrecked Parts Car.
1998 S70 T5
1996 850 N/A
1989 740 GLT
1986 740 GLT
1972 142 Grand Luxe

jimmy57
Posts: 6302
Joined: Fri Nov 12, 2010 9:25 am
Year and Model: 2004 V70R GT, et al
Location: Ponder Texas
Has thanked: 2 times
Been thanked: 154 times
jimmy57

Re: A/C pressures

Post by jimmy57 » Thu Jul 25, 2019 7:43 am

it takes 42-44 psi to get compressor on. The pressure cycling switch/pressostat opens when pressure falls to 22-25 and closes when pressure rises to 42-44. With so little refrigerant the compressor suction draws in the refrigerant and lowers pressure to near zero and the discharge pressure is probably 75-100 and it is unlikely there is anything wrong with orifice. When you do evaporator it is suggested that you separate line and remove and clean or replace orifice. The orifice has filter screen and there will always be something on it to blow off. when you put new parts in there is a good chance some filings and stuff from manufacturing are in the new parts and the orifice might be compromised with new stuff added to the existing stuff.



User avatar
abscate
MVS Moderator
Posts: 17910
Joined: Sun Feb 17, 2013 5:54 pm
Year and Model: 99T5 ,99S70,2005V70
Location: NYC, ALBANY NY
Has thanked: 192 times
Been thanked: 620 times
Trinidad & Tobago
abscate

Re: A/C pressures

Post by abscate » Thu Jul 25, 2019 7:56 am

Have fun removing the orfice from the hard line on the car. I remembered I managed to do it with two open ends, but it was a serious Charlie Foxtrot

Crows feet with wobbles would probably work well, though.


Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW

User avatar
erikv11
Posts: 9102
Joined: Sat Jul 25, 2009 2:03 pm
Year and Model: 850, S/V70, 06 S60R
Location: Iowa
Has thanked: 55 times
Been thanked: 189 times
United States of America
erikv11

Re: A/C pressures

Post by erikv11 » Thu Jul 25, 2019 8:33 am

I found the orifice super easy to replace when I did it on my 96 850. Oh, there was no engine in the car ...


'95 854 T5-R, Motronic 4.4, 185k
'96 855 NA, 140k
'98 S70 NA, 210k (living out west)
'98 V70, T5 tune-injectors-turbo, LPT engine, 280k
'06 S60 R, 160k
gone: '96 NA 850 210k, '98 NA V70 182k

User avatar
abscate
MVS Moderator
Posts: 17910
Joined: Sun Feb 17, 2013 5:54 pm
Year and Model: 99T5 ,99S70,2005V70
Location: NYC, ALBANY NY
Has thanked: 192 times
Been thanked: 620 times
Trinidad & Tobago
abscate

Re: A/C pressures

Post by abscate » Thu Jul 25, 2019 8:55 am

erikv11 wrote:
Thu Jul 25, 2019 8:33 am
I found the orifice super easy to replace when I did it on my 96 850. Oh, there was no engine in the car ...
How are those front wheel bearings looking?

:D :D :D


Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW

User avatar
greg850r
Posts: 190
Joined: Thu May 03, 2012 5:06 pm
Year and Model: a long list
Location: Mo
Has thanked: 1 time
Been thanked: 4 times
United States of America
greg850r

Re: A/C pressures

Post by greg850r » Thu Jul 25, 2019 8:59 am

Thanks guys. I was kind of hoping someone would have an idea I didn't. My son and I did the evap and heater core on our other 96. We had pieces spread out all over the garage for 3 days. We think we can do this one in a day now but we'll see.


05 Cross Country wagon
99 C70 Convertible
96 850R wagon
96 850T wagon
96 850 GLT 5spd N/A sedan
97 850R 5spd sedan
66 GTO 421SD 4spd
67 GTO 455 T400
02 Powerstroke 4x4
85 Yota 4x4
24' 454 Challenger
07 Softail Custom
02 Sportster Custom
Parts cars not included

User avatar
abscate
MVS Moderator
Posts: 17910
Joined: Sun Feb 17, 2013 5:54 pm
Year and Model: 99T5 ,99S70,2005V70
Location: NYC, ALBANY NY
Has thanked: 192 times
Been thanked: 620 times
Trinidad & Tobago
abscate

Re: A/C pressures

Post by abscate » Thu Jul 25, 2019 10:07 am

greg850r wrote:
Thu Jul 25, 2019 8:59 am
Thanks guys. I was kind of hoping someone would have an idea I didn't. My son and I did the evap and heater core on our other 96. We had pieces spread out all over the garage for 3 days. We think we can do this one in a day now but we'll see.
The second one is faster, and the third. Then you hit the plateau

Good luck - at least in MO you have to have AC - it kills us to fix it when we need it for three days.


Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW

Post Reply