r22 enthalpy diagram

A Quiz from one of my technicians: He claims this unit had these these conditions today.

R22 air coooled package airconditioning unit:
Ambient: 84f
Suction 52psig/82f
discharge 280psig/158f
LIquid at condenser 112f
the more gas added the higher the hp went!

the unit is twin compressor system. both with similar pressures...this adds to confusion!
No temp drop across driers by contact thermometer.
both indoor coil and outdoor coils clean. airflows okay as well

I have plotted the suction point to discharge point and it goes almost straight up vertically. It does not not follow the entropy line....whats wrong......been a long time since I learned this stuff!!

Mechanic tells me he evacuated so it should not be non condensables..or is it
What else could it be
Is it air or has he beaten me again!

Is the Condenser fan running at correct speed :confused: could still have non-condensables in system

Quote:

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Originally Posted by Jasper

Is the Condenser fan running at correct speed :confused: could still have non-condensables in system

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Yes condenser fans are running at correct speeds

Is it R22 or something else that was added to both systems, perhaps a mixture? Technicians carry a lot of different gases these days.

Many yaers ago when R11 was used for flushing, I came across a couple of systems in the northeast that had the remnants of R11 mixed with R22 after a burn out where the R11 had not been all removed prior to charging with R22.
Gave some unusual results, just like yours.
________
herbalaire vaporizer

Quote:

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Originally Posted by eskimo2

A Quiz from one of my technicians: He claims this unit had these these conditions today.

R22 air coooled package airconditioning unit:
Ambient: 84f
Suction 52psig/82f
discharge 280psig/158f
LIquid at condenser 112f
the more gas added the higher the hp went!

the unit is twin compressor system. both with similar pressures...this adds to confusion!
No temp drop across driers by contact thermometer.
both indoor coil and outdoor coils clean. airflows okay as well

I have plotted the suction point to discharge point and it goes almost straight up vertically. It does not not follow the entropy line....whats wrong......been a long time since I learned this stuff!!

Mechanic tells me he evacuated so it should not be non condensables..or is it
What else could it be
Is it air or has he beaten me again!

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iF YOU WANT TO CK FOR NON-CONDENSIBLES OR MIXED REFRIGERANTS DO THIS:

1. Attach a hi side pressure guage to measure condenser pressure
2 Pump down the system by closing off the liquid line service valve and make sure in dosn't leak by cking if it frosts
3 Disconnect the comp contactor on the load side so it won't run
4 turn on the power to run the condenser fans anf measure the OSA temp let it run for about 20 min and compare the PT relationship. they should be very close to correct if all is OK ;)

ISN*T too litlle 52 psig pressure in suction line forr R22 ?

Weren't you overfilling the system somehow?

checked the suction and discharge PT state points, the suction temp is higher but the dischage temp is comparatively low. and the compression line is close to isoenthalpy. would you pls confirm again ? how about the balance pressure while stop?

Argus, as far as I am aware no one has added differnt gas...but i will keep that in mind...we generally are only using r22 and r134a....would r134a if mixed with r22 give a high head pressure.

servicefrigo, 52 psig is low but add more and hp goes up even higher.

Peter, as per above would not think its overcharged

shogun, No liquid line valve to do what you say

lc shi, data given is what my technician measured.

Quote:

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Originally Posted by eskimo2

.... 52 psig is low but add more and hp goes up even higher.
Peter, as per above would not think its overcharged...

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I don't see the link between both. If you have moisture in the system and capillary is partially blocked or dryer partially blocked, whereby excess gas is stored already in condenser, adding extra gas will rise condensor pressure and slightly LP.

I haven't translated yet your Imp to SI units.

Did it now and overfilled impossible because liquid is coming out too hot
Ambient 29°C.
Suction 4,6 bar/29°C
Discharge 20 bar/70°C
Liquid 45°C

Perhaps 2 problems then: overfilled and air in the system.
I rarely believe what other say (your tech said he evacuated and recharged it)

See after re-reading now that filter isn't blocked, but perhaps moisture in the system and perhaps capillary partially blocked. Perhaps you received a gas bottle with moisture in it.

I agree with Peters theory (overfilled and air in the system ), and i'm not sure that vaccum was made to the system "real vaccum i mean "

My opinion ;75% the liquid line is almost blocked somwere.

Quote:

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Originally Posted by eskimo2

A this unit had these these conditions today.

R22 air coooled package airconditioning unit:
Ambient: 84f
Suction 52psig/82f
discharge 280psig/158f
LIquid at condenser 112f
the more gas added the higher the hp went!

the unit is twin compressor system. both with similar pressures...this adds to confusion!
No temp drop across driers by contact thermometer.
both indoor coil and outdoor coils clean. airflows okay as well

I have plotted the suction point to discharge point and it goes almost straight up vertically. It does not not follow the entropy line....whats wrong......been a long time since I learned this stuff!!

Mechanic tells me he evacuated so it should not be non condensables..or is it
What else could it be
Is it air or has he beaten me again!

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seems like you have moisture problem or it could be blocaged in system either replaced capilary or te valve

Did you check the filters ????