Air in the condenser...
 

One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

On 26 Aug 2004 12:16:13 -0700, (Marty) wrote:

One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater.

That's not why it happened. it happened because there was a
leak in a system that is supposed to be hermetically sealed.

Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

Because there was a leak.

Or ' it was European air, which is migratory, as opposed to
African air, which is not'.

Or some ****ing thing like that.

Bottom line - you need to go get yourself an education in
HVAC/R before even asking questions like that.



Paul ( pjm @ pobox . com ) - remove spaces to email me
'Some days, it's just not worth chewing through the restraints.'

HVAC/R program for Palm PDA's
Free demo now available online http://pmilligan.net/palm/
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"Marty" wrote in message
om...
One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

it doesn't migrate there it gets pumped by the compressor and due to the
nature of non condensables air gets trapped as it can't condense and flow
out of the liq line

cheers

richard

"Marty" wrote in message
om...
One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

As I see it, virtually all the refrigerant would have had to leak out to
allow air to get into the system.

How low did the refrigerant level get?

HeatMan wrote:

"Marty" wrote in message
om...

One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????


As I see it, virtually all the refrigerant would have had to leak out to
allow air to get into the system.

How low did the refrigerant level get?




Wouldn't the evap be in a vacuum at that temp or maybe a pump-down system?

MikeB

"HeatMan" wrote in message
...

"Marty" wrote in message
om...
One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

As I see it, virtually all the refrigerant would have had to leak out to
allow air to get into the system.

How low did the refrigerant level get?


Somewhere in the system the pressure got below 1 bar.

--

SVL

HeatMan wrote:
"Marty" wrote in message
om...

One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????


As I see it, virtually all the refrigerant would have had to leak out to
allow air to get into the system.

How low did the refrigerant level get?

Nope, just enough that the low side was in a vacuum.

"PrecisionMachinisT" wrote in message ...
"HeatMan" wrote in message
...

"Marty" wrote in message
om...
One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

As I see it, virtually all the refrigerant would have had to leak out to
allow air to get into the system.

How low did the refrigerant level get?


Somewhere in the system the pressure got below 1 bar.

Yes the evaporator went into a vacuum because very low temperature
and the type of refrigerant. If the set point on the reefer was say
+32F then refrigerant would have leaked out of the evaporator.

"r.bartlett" wrote in message ...
"Marty" wrote in message
om...
One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

it doesn't migrate there it gets pumped by the compressor and due to the
nature of non condensables air gets trapped as it can't condense and flow
out of the liq line

cheers

richard
I know it can't condense, but why doesnt't it flow. Because the air
is now separated from the refrigerant? Shouldn't liquid refrigerant
still be able push the air along the liquid line.

"HeatMan" wrote in message . ..
"Marty" wrote in message
om...
One time when I was on a boat to China, I had the job of baby sitting
the refrigerated container vans. One of the 'reefers' developed a leak
in the evaporater. Since the set point was -13F and the refrigerant
was R134a air leaked into the evaporater. Then the air migrated into
the condenser and caused a reduction in cooling ability and high
discharge pressure. Now here is the part I don't understand. What the
'reason' why the air migrated into the condenser??????????????

As I see it, virtually all the refrigerant would have had to leak out to
allow air to get into the system.

How low did the refrigerant level get?

The refrigerant level was normal. Refrigerant was not leaking out of
the unit air was leaking into the system.

Try to imagine a big, glass, about a galon pickle jar.

drill a hole in the bottom of the pickle jar. Put a tube on the bottom. Put
in an inch or so of water.

Drill a hole along the side, near the top. Pump in a little air, and some
water.

Keep draining water out of the bottom. The air is still trapped in the jar.

Crude, but the kind of idea.

The air is above the liquid refrig. the liquid line to the evaporator comes
off the bottom of the condensor.

--
Christopher A. Young

Do good work.
It's longer in the short run,
But shorter in the long run.


"Marty" wrote in message
om...

I know it can't condense, but why doesnt't it flow. Because the air
is now separated from the refrigerant? Shouldn't liquid refrigerant
still be able push the air along the liquid line.