Cool Room Problem

I have a cool room running on R22. 1-4 degrees C.
There have been problems with this room for some time.

I put my gauges on and am reading 310kpa suction and high side is a stable 1500kPa,(With a variable speed Fan). I pumped the system down to 30kPa and it tripped on HP. When I checked the high side, Liquid was in my manifold.:eek: .

I bled a substantial amt of refrigerant into a reclaim cylinder. Decided to run the system again to check. My LP dropped to 110Kpa.:eek: .

Pumped it down again to 0kpa and did not trip HP.:cool: .

Did some pipe work and ran it again. Same pressures and my suction line was frosting bad. I checked refrigerant charge and it seemed OK.

I checked the superheat.........25K...:eek: :eek: :eek: .

I began to adjust....14K......12K....................12K...............Even with TXV fully open, I was still only getting 12K.

But.......................The compressor began to "ICE" and oil was foaming and rapidly leaving the compressor. OMG! what is going on. I watched oil pass through the LL sight....:eek: :eek: ....







To be continued..................................................





What is the general consensus on the problem here?
I will update with my remedy but I'd like to know if anyone has come across a similar problem.

Evaporator too small or compressor too big and it was overcharged.
Or some of the circuits are blocked in the evaporator.
Give us type and brand names of both compressor and evaporator.
Is there a receiver? Capacity?

evap blocked or fan not running

either way you've got the superheat figure wrong..

cheers

richard

ps we love pic's ;-)

not something daft like the evap fan stop temperature set far to low !f***d expansion valve,burst heat exchager or previous sugestions.burp, this wines tastes lovley !!!

mmmmm. put you thinking caps on fellas.

The evap, compressor(bitzer), condener and reciever are all sized correctly. TXV is an externally equalising Danfoss TE2. As I said I have remedied. I did not have to change any componentry.

It had me stumped for some time. I'll try to get pics next week.

Old gas bottle mage a good suggestion... inside of teh heat exchanger burst.

Quote:

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Originally Posted by hybridjunction

mmmmm. put you thinking caps on fellas. .

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We need at least all the info we ask for that. My thinking cap is always on.

Quote:

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The evap, compressor(bitzer), condener and reciever are all sized correctly. TXV is an externally equalising Danfoss TE2.

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Sure?? What orifice?

How long is this installation already running?
And running without serious problems?
Did the problems happened at once?
Have you installed it?
Have others serviced it in the meanwhile?

All important questions. Listening to the customer (not always believing them) can give valuable clues to eliminate probably causes..

Quote:

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Originally Posted by hybridjunction

I have a cool room running on R22. 1-4 degrees C.
There have been problems with this room for some time.

I put my gauges on and am reading 310kpa suction and high side is a stable 1500kPa,(With a variable speed Fan). I pumped the system down to 30kPa and it tripped on HP. When I checked the high side, Liquid was in my manifold.:eek: .

I bled a substantial amt of refrigerant into a reclaim cylinder. Decided to run the system again to check. My LP dropped to 110Kpa.:eek: .

Pumped it down again to 0kpa and did not trip HP.:cool: .

Did some pipe work and ran it again. Same pressures and my suction line was frosting bad. I checked refrigerant charge and it seemed OK.

I checked the superheat.........25K...:eek: :eek: :eek: .

I began to adjust....14K......12K....................12K...............Even with TXV fully open, I was still only getting 12K.

But.......................The compressor began to "ICE" and oil was foaming and rapidly leaving the compressor. OMG! what is going on. I watched oil pass through the LL sight....:eek: :eek: ....







To be continued..................................................





What is the general consensus on the problem here?
I will update with my remedy but I'd like to know if anyone has come across a similar problem.

---

It's not R22, somebody has added something else either a partial recharge on top of the R22 or a complete charge.
Reclaim the gas vac and start again

Kind Regards. Andy:)

Quote:

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Originally Posted by hybridjunction

I checked the superheat.........25K...:eek: :eek: :eek: .

I began to adjust....14K......12K....................12K...............Even with TXV fully open, I was still only getting 12K.

But.......................The compressor began to "ICE" and oil was foaming and rapidly leaving the compressor. OMG! what is going on. I watched oil pass through the LL sight....:eek: :eek: ....

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Unit was flooding back so superheat readings are definitely not right.

I think Andy has the right answer.

Quote:

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I have a cool room running on R22.

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then why did he start by saying this?

cheers

richard

mmm.............

maybe the sticker on it said r22?

Quote:

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Originally Posted by Temprite

mmm.............

maybe the sticker on it said r22?

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as my dad would say "it says Oxo on the back of busses -but it doesn't mean the conductor sells it"

However the poster said "I have a coldroom running on R22-not I have a coldroom with an R22 system".

there is a difference and the first statement explicitly excludes mis refrigerant or a mixture...

Cheers

Richard

Quote:

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Originally Posted by rbartlett

as my dad would say "it says Oxo on the back of busses -but it doesn't mean the conductor sells it"

However the poster said "I have a coldroom running on R22-not I have a coldroom with an R22 system".

there is a difference and the first statement explicitly excludes mis refrigerant or a mixture...

Cheers

Richard

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Hi Richard:)
A label might have indicated R22, but the last guy to work at it might have onlt had R404a left and it was short of gas:D

Only time I have seen this is with contaminated gas or in one case the EEV was set for R404a when it was actually R22.

Kind Regards. Andy:)

Quote:

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Originally Posted by Andy

Hi Richard:)
A label might have indicated R22, but the last guy to work at it might have onlt had R404a left and it was short of gas:D

Only time I have seen this is with contaminated gas or in one case the EEV was set for R404a when it was actually R22.

Kind Regards. Andy:)

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this may or may not be relevent to this problem but-

you can't set a riddle by starting out saying "I have xx what's wrong?" then come back and say "I actually had yy and you're rubbish at solving riddles".



cheers

richard

MArc???
Sorrry,..no..it's Richard.
It's therefore usefull to listen to the customer if others have worked on the system.

Quote:

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Originally Posted by Peter_1

MArc???
Sorrry,..no..it's Richard.
It's therefore usefull to listen to the customer if others have worked on the system.

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Had that thought also:D

Richard hows Marc:)

Kind Regards. Andy:)

Andy has it fellas. Some goose had given the system an oil change and Put a mix or R134a/R22 in the system. It also had a mix of mineral and POE oil. Richard, I do have a cool room running on R22 NOW. I had to recover the charge, do an oil change and disconect the evap to flush residiual oiil out.


Unbelievalbe. For 2 days my instuctors told me that there was nothing wrong, that I didn't know how to read gauges and temperatures. I felt like shoving gas bottle up each of their Pee Holes.


Next time they should take me a bit more serious. I hope.


Is this something that is come across in common servicing???

.................................................................................................... .....................................................

G'day hybridjunction.

Have come across it before but I wouldnt say that it is common.

The worst case of mixed gasses I ever saw was R12 and SP34E mixed together on a temprite bevarage cooler which is a flooded system, caused real problems with the beer temp.

If you think it is acting strange putting in a known gas will at least eliminate that possibility.

And due to this worst case ,you got your nickname :D

Quote:

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Originally Posted by hybridjunction

Andy has it fellas. Some goose had given the system an oil change and Put a mix or R134a/R22 in the system. It also had a mix of mineral and POE oil. Richard, I do have a cool room running on R22 NOW. I had to recover the charge, do an oil change and disconect the evap to flush residiual oiil out.


Unbelievalbe. For 2 days my instuctors told me that there was nothing wrong, that I didn't know how to read gauges and temperatures. I felt like shoving gas bottle up each of their Pee Holes.


Next time they should take me a bit more serious. I hope.


Is this something that is come across in common servicing???

.................................................................................................... .....................................................

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More common than people care to admit.;)

If you have poor superheat control, and unexplained flood back, it is a good idea to change out the expansion valve (check the selection at the exact pressure drop and subcooling) and remove the gas and start again.

I had a 200kW blast freezer on R502 changed to 69L with a few bottles of R22 threw in by previous engineers. Discharge temps were way too high, head pressure low and evaporator performance very poor, basically eating electric and burning out semihermetic compressor like Iceland Pots.

As a stroke of good luck it was also piped in steel DIN pipe and the liquid line let go one night.

I arrived the next evening, only 1/2 a 60kg bottle left.

The 69L was very expensive to replace, so I decided to change the control chip to R22 and the gas. Pressure tested the system, repaired the liquid line and a small leak on the botton of one of the cooler headers, vacumned it all out and added R22 (8 bottles).

That was 3 years ago and the plant is a new plant, no compressors going down, no poor performance and no leaks.

If in doubt change out the as and stsrt again;) its the cheaper option.

Kind Regards. Andy:)

Quote:

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Originally Posted by Peter_1

And due to this worst case ,you got your nickname :D

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:D :D
I am glad to report that it wasn't me.

Regarding temprites I remember sometime back Peter that you had read something on an antique beverage cooler and I had said I knew someone who had an old manual on them.

I havent been able to get the old manual but if your still interested I will get some photos.

There are quite a few systems getting replaced with glycol now.

Have got quite a few lying around not being used.

Regards.

I'm always interested in antique itmes, refr. related.
My mother in law is..no.. forget it.

Hi Temprite. While you on the subject of temprites, just wondering if this is the only application for a 750valve?




I googled 750valve but came up wih squat. Oh if anyone knows where I might be able to find an old temprite system for sale, (doesn't have to be working), in Australia, please PM me.



Cheers



Question about the mixed refrigerant senario, Would it be possible to take a sample or use a temp prob with gauges to check the refrigerant or would the temps and pressure of a mixed refrigerant (ie. R134a and R22) be too close to make an accurate distinction???

G'day hybridjunction.

As far as I am aware this is the only use for a 750 valve.

Obviously EPR valve use is widespread but not in the form of a 750 valve.

I have a stand alone temprite self contained cooler that has no condensing unit that you could buy but you would have to come to Victoria to get it.

Regards.

Quote:

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Originally Posted by hybridjunction

Hi Temprite. While you on the subject of temprites, just Question about the mixed refrigerant senario, Would it be possible to take a sample or use a temp prob with gauges to check the refrigerant or would the temps and pressure of a mixed refrigerant (ie. R134a and R22) be too close to make an accurate distinction???

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You can only do this with a mass spectrometer.

Thanks temprite. I'll get back to you on that one.

Quote:

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Originally Posted by Temprite

:D :D
I am glad to report that it wasn't me.

Regarding temprites I remember sometime back Peter that you had read something on an antique beverage cooler and I had said I knew someone who had an old manual on them.

I havent been able to get the old manual but if your still interested I will get some photos.

There are quite a few systems getting replaced with glycol now.

Have got quite a few lying around not being used.

Regards.

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Peter some photos of that "antique" that I was talking about.

Low side float in it's simplest form.

Pressure kept constant by EPR or 750 valve as it is refered to.

These systems are being removed quite often and replaced by glycol as photo shows.

Quote:

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Originally Posted by hybridjunction

I have a cool room running on R22. 1-4 degrees C.
There have been problems with this room for some time.

I put my gauges on and am reading 310kpa suction and high side is a stable 1500kPa,(With a variable speed Fan). I pumped the system down to 30kPa and it tripped on HP. When I checked the high side, Liquid was in my manifold.:eek: .

I bled a substantial amt of refrigerant into a reclaim cylinder. Decided to run the system again to check. My LP dropped to 110Kpa.:eek: .

Pumped it down again to 0kpa and did not trip HP.:cool: .

Did some pipe work and ran it again. Same pressures and my suction line was frosting bad. I checked refrigerant charge and it seemed OK.

I checked the superheat.........25K...:eek: :eek: :eek: .

I began to adjust....14K......12K....................12K...............Even with TXV fully open, I was still only getting 12K.

But.......................The compressor began to "ICE" and oil was foaming and rapidly leaving the compressor. OMG! what is going on. I watched oil pass through the LL sight....:eek: :eek: ....







To be continued..................................................





What is the general consensus on the problem here?
I will update with my remedy but I'd like to know if anyone has come across a similar problem.

---

sounds like txv faulty going on past experience
would like to know the outcome

Sizing mismatch.
Refrigerant ****tail.
Check Evap, condensing unit, TXV and pipe sizing.

Quote:

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Originally Posted by Temprite

G'day hybridjunction.

Have come across it before but I wouldnt say that it is common.

The worst case of mixed gasses I ever saw was R12 and SP34E mixed together on a temprite bevarage cooler which is a flooded system, caused real problems with the beer temp.

If you think it is acting strange putting in a known gas will at least eliminate that possibility.

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Interested in your comment Temprite. I have had contractors tell me they have mixed sp34e and R12 on many temprite systems in Qld and swear they have worked well without problems! I have not seen any examples,but logic tells me to be extremely skeptical. As an ex Vic I had many years exp on R12 temprite systems.

G'day DeB

This particular system was on R12 and someone topped the charge up with SP34E after a gas leak.Result was that several of the Temprites froze.750 valves were altered but still could not get stable operation

The gas was removed and the system was charged with only SP34E, which rectified all problems.

Ater that have never bothered trying to mix the two gasses to see if it affects operation

I have seen mixed gasses in a temprite since though.

A temprite system charged with isceon 49 was topped up with 34M, it operated fine with no adjustment to 750 valves.

One thing I have noticed though is occcasionly you will get a temprite that will not operate satisfactorly on anything other than R12.When you put in the drop in replacement the temprite has no recovery and pours warm after 2 beers, put the R12 back in and you can pour 6 in a row without much temperature difference. Never been able to come up with an answer for that one.:)

Quote:

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Originally Posted by Temprite

G'day DeB

This particular system was on R12 and someone topped the charge up with SP34E after a gas leak.Result was that several of the Temprites froze.750 valves were altered but still could not get stable operation

The gas was removed and the system was charged with only SP34E, which rectified all problems.

Ater that have never bothered trying to mix the two gasses to see if it affects operation

I have seen mixed gasses in a temprite since though.

A temprite system charged with isceon 49 was topped up with 34M, it operated fine with no adjustment to 750 valves.

One thing I have noticed though is occcasionly you will get a temprite that will not operate satisfactorly on anything other than R12.When you put in the drop in replacement the temprite has no recovery and pours warm after 2 beers, put the R12 back in and you can pour 6 in a row without much temperature difference. Never been able to come up with an answer for that one.:)

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I'm with you on temprites. They can be temperamental. Do you think the problem may be oil logging in the temprite? I have seen oil logged temprites that cause the same problem. Also "noisy" temprites that are still noisy after 750 and cartridge change. Any thoughts on that one?

how to dettermined lost compression on scrol type compressor?

I think you should recheck your superheat! ensure you fit a good temp probe on the outlet of the evaporator after the equalizing line! you should have 7k on top of your saturated suction temp..(ie. guage pressure converted to temp!) if the superheat is lower than 7k even after closing down the valve then you have an oversized orifice!. or a leaking heat exchanger as previously decribed!

Quote:

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Originally Posted by DeB

I'm with you on temprites. They can be temperamental. Do you think the problem may be oil logging in the temprite? I have seen oil logged temprites that cause the same problem. Also "noisy" temprites that are still noisy after 750 and cartridge change. Any thoughts on that one?

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Sorry must have missed this post.

The offending temprites were all drained of oil, as you say does cause the same symptoms but not in this case.

regards.