Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 22-05-2014, 10:56   #1
Registered User

Join Date: Apr 2012
Location: Panama Atlantic Side
Boat: Whitby 42
Posts: 20
Refrigeration Problem

I have been fighting refrigeration problems for the last 4 years but this problem has me stumped. I have a separate freezer unit with two large holding plates run by a Danfoss compressor with a capillary tube. The plates run in series first to the plate with the capillary tube then out of the box to the plate on the other side of the box then back to the compressor (Normal). The unit was working properly with both plates frosting and the temp of the box freezing things properly. Then the first plate (the one with the capillary tube refused to frost up and went to box temp.. I assumed that I had too much Freon and over a couple of day reduce the charge until I was down to 2 psi and the second plate would not freeze. I was in the middle of nowhere so I increase the Freon to about 14 psi froze the second plate and a length of the return tube and reduced the box size This got me through the season. Now I am In the Rio Dulce try to figure it out. I checked and the plate is full of “antifreeze”. Does anyone have any subjection as to where I should go from here?
Some history the last thing done to this unit was the installation of a dryer, vacuumed and Freon. This was two weeks before the problem.
Steve
lions paw is offline   Reply With Quote
Old 22-05-2014, 11:00   #2
Registered User
 
Cavalier's Avatar

Join Date: Dec 2010
Location: Houston, TX
Boat: Beneteau 461 47'
Posts: 927
Images: 1
Re: Refrigeration Problem

Quote:
Originally Posted by lions paw View Post
I have been fighting refrigeration problems for the last 4 years but this problem has me stumped. I have a separate freezer unit with two large holding plates run by a Danfoss compressor with a capillary tube. The plates run in series first to the plate with the capillary tube then out of the box to the plate on the other side of the box then back to the compressor (Normal). The unit was working properly with both plates frosting and the temp of the box freezing things properly. Then the first plate (the one with the capillary tube refused to frost up and went to box temp.. I assumed that I had too much Freon and over a couple of day reduce the charge until I was down to 2 psi and the second plate would not freeze. I was in the middle of nowhere so I increase the Freon to about 14 psi froze the second plate and a length of the return tube and reduced the box size This got me through the season. Now I am In the Rio Dulce try to figure it out. I checked and the plate is full of “antifreeze”. Does anyone have any subjection as to where I should go from here?
Some history the last thing done to this unit was the installation of a dryer, vacuumed and Freon. This was two weeks before the problem.
Steve
Steve,

Some plates are designed with an inbuilt passive bypass. i.e. there'll be a very small diameter cavity that runs from the inlet to the outlet. Most of the time the majority of the coolant will evaporate throughout the main bore of the system. In the event that the main bore becomes blocked, or restricted etc. (due to internal corrosion or foreign particles), then the Freon will bypass most of the plate and transfer to the outlet at a much lower rate.

This may explain why your second plate still works (down to a low pressure) but the first plate in series has stopped functioning. If this is the case then you're unlikely to notice any change in the performance of the compressor, as the blockage would only have affected the

If you have a vacuum and Freon charging system available (sounds like it). You could consider removing the blocked plate from the system to see how well the second (functioning) plate works. Alternatively, you could remove the functioning plate and confirm that the first plate is blocked.

Phil
__________________
"By day the hot sun fermented us; and we were dizzied by the beating wind. At night we were stained by dew, and shamed into pettiness by the innumerable silences of stars."
Cavalier is offline   Reply With Quote
Old 22-05-2014, 11:10   #3
Registered User

Join Date: Apr 2012
Location: Panama Atlantic Side
Boat: Whitby 42
Posts: 20
Re: Refrigeration Problem

The system in Question was made by EZ Kold in Canada they have since gone out of business, I have no charge data.
Steve
lions paw is offline   Reply With Quote
Old 22-05-2014, 11:17   #4
Registered User

Join Date: Apr 2012
Location: Panama Atlantic Side
Boat: Whitby 42
Posts: 20
Re: Refrigeration Problem

Phil
Thanks for the great info.
Would vacuuming the system possibly clear the blockage? Or possibly hitting it with a big hammer.
Steve
lions paw is offline   Reply With Quote
Old 22-05-2014, 11:24   #5
Registered User
 
Cavalier's Avatar

Join Date: Dec 2010
Location: Houston, TX
Boat: Beneteau 461 47'
Posts: 927
Images: 1
Re: Refrigeration Problem

Quote:
Originally Posted by lions paw View Post
Phil
Thanks for the great info.
Would vacuuming the system possibly clear the blockage? Or possibly hitting it with a big hammer.
Steve
It's not 100% certain that the plate has a bypass. However, the Freon is getting to the second panel (in series) somehow, so it'd make sense that it does. Once you've removed it from the system, you'll be able to verify that the issue is with that particular panel.
Your best bet is to back-flush the system with alcohol (isopropanol or denatured). If you have corrosion issues, the last thing you want is to have more water introduced into the system. When you re-vacuum the system afterwards you'll easily pull the alcohol vapor out of the system. Back-flushing is probably the best way of clearing a possible blockage which would have plugged due to the direction of flow of the Freon. Reversing that flow should help unplug it.

Good luck, and I hope this was the problem.
__________________
"By day the hot sun fermented us; and we were dizzied by the beating wind. At night we were stained by dew, and shamed into pettiness by the innumerable silences of stars."
Cavalier is offline   Reply With Quote
Old 22-05-2014, 11:41   #6
Marine Service Provider
 
SV THIRD DAY's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: La Paz, Mexico
Boat: 1978 Hudson Force 50 Ketch
Posts: 3,920
Re: Refrigeration Problem

The 4 Ez Cool systems I have worked on have no bypass from plate one into plate two, you simply have two plates plumbed in series, with a critical orifice at the entrance to plate one. So the two plates are basically being treated like one large evaporator along with the interconnecting copper tube.This sure points to a charge issue (90% of refrigeration problems are) if the compressor is running but the plate or plates are not getting cold or if your return line is frosting up.

Based on your comment of having a frosty return line back to the compressor, it sure sounds like you are now over charged, so here is what I would do next. SLOWLY let small spurts of refrigerant out of the system. We are talking SLOWLY like testing your patience slow. The hard part about trying to "SWAG" the proper charge on a holding plate system as compared to a flat evaporation plate is that until your plates are frozen the sytem won't be in equilibrium so it EASY to way over charge because of the time delay in making adjustments.

It's certainly possible that you have an orfice blockage...but it's less drama to play with the charge than do a refrigerant loop cleaning...so that is where I would start...easy things first.

PS: is this the same Lion's Paw with the Cat "Cortez" I cruised with in Mexico?
__________________
Rich Boren
Cruise RO & Schenker Water Makers
Technautics CoolBlue Refrigeration
SV THIRD DAY is offline   Reply With Quote
Old 22-05-2014, 11:44   #7
Registered User

Join Date: Apr 2012
Location: Panama Atlantic Side
Boat: Whitby 42
Posts: 20
Re: Refrigeration Problem

Thanks Phil
The plate with the problem is the one with the capillary tube. Is it Ok to back flush through the tube?
Steve
lions paw is offline   Reply With Quote
Old 22-05-2014, 12:02   #8
Registered User
 
Cavalier's Avatar

Join Date: Dec 2010
Location: Houston, TX
Boat: Beneteau 461 47'
Posts: 927
Images: 1
Re: Refrigeration Problem

Quote:
Originally Posted by SV THIRD DAY View Post
The Ez Cool systems have no bypass from plate one into plate two, you simply have two plates plumbed in series, with a critical orifice at the entrance to plate one. So the two plates are basically being treated like one large evaporator along with the interconnecting copper tube. This sure points to a charge issue (90% of refrigeration problems are) if the compressor is running but the plate or plates are not getting cold or if your return line is frosting up.

Based on your comment of having a frosty return line back to the compressor, it sure sounds like you are no over charged, so here is what I would do next. SLOWLY let small spurts of refrigerant out of the system. We are talking SLOWLY like testing your patience slow.
Steve,

Based on what Third Day is stating about the absent bypass, and the fact that one plate cools fine and the other doesn't (even though they're in series), leads me to think this isn't a charging problem.

One possibility, therefore, is that you have a severe constriction at or very near to the outlet of the first plate. When the Freon floods the system after compression, then it'd be incapable of expanding (evaporating) in the first plate due to the constriction at the outlet. The [possible] constriction at the outlet would then permit the coolant to expand into the second plate volume properly meaning it can cool. Basically, you may have an artificial valve placed between the two plates...

Hope this is a helpful addition to the conspiracy theories surrounding your refrigeration system.

I would consider washing alcohol backward and forward to ensure the flow matches the apparent bore of the plate.
__________________
"By day the hot sun fermented us; and we were dizzied by the beating wind. At night we were stained by dew, and shamed into pettiness by the innumerable silences of stars."
Cavalier is offline   Reply With Quote
Old 22-05-2014, 12:14   #9
Registered User

Join Date: Apr 2012
Location: Panama Atlantic Side
Boat: Whitby 42
Posts: 20
Re: Refrigeration Problem

Rich
Thanks for your response.
No there is no site glass. I have gages hooked up to it. Near the end of its cycle they read 8 psi, there is frost on the return tube but no frost on the tubes between the two plates. When the unit is off the gages read about 18 psi. Marvin at EZ Kold had told me about 12 was normal but my system seemed to run better at 18 to 20 and he said that was fine. When I first had the problem I spilled the Freon until it was about 2 psi and it didn’t make any difference other that have a hard time freezing the second plate.


Rich didn't see the second part of your message.

Actually this is a great time to bring the plates down to room temp. As we are putting it up for a couple of months. It may be a week or so but I will give it a try. Should I leave some charge in the system to make sure I don’t let in any air?
Steve
lions paw is offline   Reply With Quote
Old 22-05-2014, 12:32   #10
Marine Service Provider
 
SV THIRD DAY's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: La Paz, Mexico
Boat: 1978 Hudson Force 50 Ketch
Posts: 3,920
Re: Refrigeration Problem

To make sure we are on the same page:

The first holding plate in series, I presume is in your freezer with the second being in the refrigerator, which is how others I have seen are set-up.
Where is your thermostat....fridge or freezer? I ask because with one compressor like this set-up you are basically controlling the temperature (off/on of the compressor) of only one plate and then the other plate is left uncontrolled. Getting a full image of the unit helps in the trouble shooting.
__________________
Rich Boren
Cruise RO & Schenker Water Makers
Technautics CoolBlue Refrigeration
SV THIRD DAY is offline   Reply With Quote
Old 22-05-2014, 14:07   #11
Marine Service Provider
 
Scott Berg's Avatar

Join Date: Jul 2011
Location: Aboard
Boat: Seaton 60' Ketch
Posts: 1,338
Re: Refrigeration Problem

I'd evacuate it, flush both ways with nitrogen, vac it down to 500 microns for a few hours, and recharge it.
__________________
Scott Berg
WAØLSS
SV CHARDONNAY
Scott Berg is offline   Reply With Quote
Old 22-05-2014, 16:30   #12
Marine Service Provider

Join Date: Aug 2004
Location: Ft. Lauderdale
Posts: 1,885
Re: Refrigeration Problem

Lions Paw, Dual holding plates on this system have nothing to do with improper super heat. Problem is either incorrect refrigerant charge or refrigerant flow is restricted by moisture sludge. Refrigerant charge volume should be set to refrigerant low pressure setting of 6 to 10 psi, 15 minutes after startup. Super heat then should frost over at least the first plate. If not stable in this range increase suction pressure to 11 psi. Let unit run at least two to 10 hours without changing suction pressure.

If correct refrigerant has not caused frost on both plates and this is a water cooled E Z Kold then you must consider a small amount of seawater has leaked from another failed condenser into refrigerant common on E Z Kold systems. I have warned boaters with E Z Kold units not to run the cooling water pump for 12 years now as it appears they will all fail at some point. Just before they went out of business they started using a larger what looked like homemade water condenser.

Unfortunately there is no solution when these small water cooled systems sludge up because the acid corrosion can not be completely removed.
Richard Kollmann is offline   Reply With Quote
Old 23-05-2014, 07:35   #13
Registered User

Join Date: Apr 2012
Location: Panama Atlantic Side
Boat: Whitby 42
Posts: 20
Re: Refrigeration Problem

Rich
Sorry I had to be away from the Computer
Both plates are in the same box and the thermostat is on the second plate. I have two compressors and two sets of plate, one for the frig and one for the freezer
Steve
lions paw is offline   Reply With Quote
Old 23-05-2014, 07:45   #14
Registered User

Join Date: Apr 2012
Location: Panama Atlantic Side
Boat: Whitby 42
Posts: 20
Re: Refrigeration Problem

Richard
Thanks for your response
Two years ago when Marvin was still around I was losing Freon through the heat exchangers on both my frig and freezer units. With Marvin’s instructions I removed the water cooling systems from each Unit. This was in the San Blass islands Panama.
Steve
lions paw is offline   Reply With Quote
Old 23-05-2014, 18:49   #15
Marine Service Provider

Join Date: Aug 2004
Location: Ft. Lauderdale
Posts: 1,885
Re: Refrigeration Problem

I think E Z Kold condenser failures are a troublesome story for many boaters. When electrolysis eats through seawater condensers acid sludge forms and complete system at some point is destroyed. Problems begin with a loss of refrigerant and later after adding more refrigerant, water, and compressor oil form an acid sludge that coats and corrodes copper tubing including holding plate coils. Steve, if you are lucky and do the refrigerant volume test I suggested it may prove that the action taken by removing water cooling prevented seawater from mixing with refrigerant.


Here is a resent short story of a local live aboard boater’s experience with a single E Z Kold dual plate water cooled system like yours:
  • System would not hold refrigerant and after several visits from refrigeration tech manufacturer had complete system returned to factory including holding plates.
  • Owner purchased a new compressor condensing unit that was upgraded with a different seawater condenser.
  • Owner paid tech to install new system with holding plates returned from E Z Kold.
  • System operated OK for a short time but only one plate got cold.
  • I went to the boat and played with refrigerant volume and determined there was a refrigerant flow problem.
  • Owner remove complete system from boat including lines and brought it to me.
  • I opened up all solder joints looking for a restriction and found a thick mass of oil. Normally refrigerant keep tube interiors shinny all these copper lines were black.
  • I spent three days flushing system out and replacing all copper tubing and a new capillary tube.
  • Next day back in boat same problem all over again.
  • It would seem the new Compressor/condenser became contaminated from sludge left in plates. Owner assumed they were flashed out at E Z Kold.
I have never charged for labor if I could not correct the problem so the $2000 dollars repair costs charged by E Z Kold and others is a sad storey. Now with almost $4000 in a small ice box conversion unit owner is going to purchase another brand’s air cooled Danfoss compressor system. In 2000 I warned about these failures after I removed three bad condensers. Was informed then the bad units I had were isolated cases.
Richard Kollmann is offline   Reply With Quote
Reply

Tags
refrigeration

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Refrigeration Problem lions paw Marine Electronics 3 22-05-2014 09:07
Need help with odd refrigeration problem brankin Electrical: Batteries, Generators & Solar 8 14-07-2013 22:18
Refrigeration problem sneuman Construction, Maintenance & Refit 0 16-10-2012 11:57
Battery-Charging Regulator Problem ? MasterVolt Problem ? RJV Electrical: Batteries, Generators & Solar 18 06-11-2011 22:53
Grunert Passagemaker Refrigeration Problem bstreep Construction, Maintenance & Refit 7 21-09-2011 17:56

Advertise Here


All times are GMT -7. The time now is 07:29.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.