Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 05-09-2014, 10:54   #16
Registered User

Join Date: Jul 2012
Boat: Tayana 58 DS
Posts: 661
Re: Basic Boat Refrigeration DIY

If you have an opportunity to evacuate the system, install service valves high and low and replace the filter-drier. Then, pressurize the system with nitrogren.

I recently installed a refrigeration system on my boat. I found leaks at 250psi (of Nitrogen) that were not evident at 35psi.

Once you're satisfied the system holds nitrogen at high pressure (for a while), evacuate and load with refrigerant.

Gauges, pump, nitrogen tank, and regulator are not very expensive to buy, but you may be able to borrow them instead.
__________________

__________________
accomplice is offline   Reply With Quote
Old 05-09-2014, 10:59   #17
Registered User

Join Date: Jul 2012
Boat: Tayana 58 DS
Posts: 661
Re: Basic Boat Refrigeration DIY

oh, and you can inject a flourescent dye when adding the refrigerant (to an empty system, is harder to do if already under pressure) which shows up under uv/blue lamp.

i haven't done this personally, but have seen it done and it can help to identify source of leaks.
__________________

__________________
accomplice is offline   Reply With Quote
Old 05-09-2014, 11:05   #18
Registered User

Join Date: Jul 2012
Boat: Tayana 58 DS
Posts: 661
Re: Basic Boat Refrigeration DIY

Quote:
Originally Posted by Dockhead View Post
Is there a book? Marine refrigeration for idiots?
One that I remember was a good book for troubleshooting was Doolin's Troubleshooters Bible.
__________________
accomplice is offline   Reply With Quote
Old 05-09-2014, 11:21   #19
Registered User

Join Date: May 2008
Location: daytona beach florida
Boat: csy 37
Posts: 2,844
Images: 1
Re: Basic Boat Refrigeration DIY

Best refrigeration book for cruisers is by Richard Kollman. Go to his website to order it.
__________________
Take two at low eight
onestepcsy37 is offline   Reply With Quote
Old 05-09-2014, 12:21   #20
Registered User

Join Date: Jul 2013
Location: San Diego, CA
Posts: 3,157
Re: Basic Boat Refrigeration DIY

They sell freon sniffers. The one I played with was extremely sensitive, it would beep if you breathed near it. Amazon sells a nice one for $47.

My neighbor had a 2.5 ton A/C on his house, way too small. He had it replaced a yr ago with a 4 ton, really close to the right size. Something went wrong with the install or the new unit, after countless calls and their techs unable to find out why it wasn't cooling, they ripped the entire system out - FAU, condenser, all copper piping and started over with a 5 ton unit free of charge, to make up for the aggravation. The new one works.

Sometimes, even the "professionals" get stumped.

We're very fortunate to have Richard's level of knowledge available to us, many professionals never achieve the level of diagnostic skill he possesses, they just burn through your money throwing parts at it until they accidentally "fix" it.
__________________
socaldmax is offline   Reply With Quote
Old 05-09-2014, 12:54   #21
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,033
Re: Basic Boat Refrigeration DIY

Sniffers can be quite tricky to use for small leaks. Among other things, the sniffer's tip can be contaminated, and any air movement in the area (i.e. a fan) makes them useless.

For a small leak, I'd suggest adding UV dye to the refrigerant, letting it run, and then coming back every week or so with a UV inspection light to try finding the dye marking the leak. UV lamps complete with dye injection kits are commonly sold and not terribly expensive. You can buy refrigerant with a dye charge mixed into it, and you can buy bright UV flashlights and a yellow goggle (increases contrast, makes the dye much easier to spot) and do it piecemeal as well.

Given that it is taking years to lose enough to create a problem, and how cheap and easy it is to add R134a (assuming that's what it uses) waiting and watching for a UV dye stain will give you a cheap way to see just what the larger problem is.

There are also whole courses (leading to US-EPA certification to deal in refrigerants) online, to get the bigger picture. But for "serious" repairs you need a good vacuum pump, which isn't cheap. Plus the gauge set, which is used for one type of refrigerant only, plus you still need the leak detection bits, plus....You know, like chess & poker, the rules are very simple, the game is very easy.(G)

A UV kit and some patience will make it easy to find the leak, assuming you can actually SEE into ALL the odd places. If it is in the evaporator coils, etc., it may be quite hard to observe, even with the UV. Which still can mean "if I can't see any leaks, it must be in the piece I can't look into."
__________________
hellosailor is offline   Reply With Quote
Old 05-09-2014, 12:59   #22
Registered User

Join Date: Jul 2012
Boat: Tayana 58 DS
Posts: 661
Re: Basic Boat Refrigeration DIY

Quote:
Originally Posted by hellosailor View Post
But for "serious" repairs you need a good vacuum pump, which isn't cheap.
It isn't fast, but I picked up a Robinair 1.5cfm pump for about $85. If you're willing to let it run for a while (hour?). It isn't commercial-duty -- so don't expect to use it every day.
__________________
accomplice is offline   Reply With Quote
Old 05-09-2014, 13:25   #23
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,033
Re: Basic Boat Refrigeration DIY

Sounds like you got lucky and got a bargain on a used vacuum pump, assuming that one pulls the vacuum down enough for those systems. If Dockhead just wants to go out and BUY what he needs, new and not trolling around for used...It won't be $85, will it?
__________________
hellosailor is offline   Reply With Quote
Old 05-09-2014, 13:52   #24
Marine Service Provider

Join Date: Aug 2004
Location: Ft. Lauderdale
Posts: 784
Re: Basic Boat Refrigeration DIY

Using fluorescent dye is bad advice if used to test for refrigerant leaks on small BD compressor systems. If you must use this dye it should be limited to only 2 drops and not the 1/4 ounce recommended for automobiles.

Also Bad advice to leak test with 250 psi of nitrogen as it can destroy Roll-bond thin plate aluminum evaporators. One hundred and fifty psi should be maximum test pressure and even then on older evaporators pressures above normal conditions may open weak spot pin holes common on units more than 10 years old.

General advice to add refrigerant is also bad if loss of refrigerant is not confirmed by a non destructive method first, Examples, adding refrigerant to a Frigoboat keel cooler system with a restricted capillary tube may limit Frigoboat’s possible recommended repair fixes or it may cause owner to scrap an EZ Kold complete system with a failed water cooling condenser.

I have practiced and guided technical services from remote locations for almost 60 years. If a person is smart enough to operate a boat they are capable of most DIY pleasure boat refrigeration repairs. NO, you do not need to buy my books as most all guidance is available free on my web site. What you must know first is the possible weak points in the system you have, this information can generally be found on the web.
__________________
Richard Kollmann is offline   Reply With Quote
Old 05-09-2014, 13:57   #25
Registered User

Join Date: Jul 2012
Boat: Tayana 58 DS
Posts: 661
Re: Basic Boat Refrigeration DIY

Quote:
Originally Posted by hellosailor View Post
Sounds like you got lucky and got a bargain on a used vacuum pump, assuming that one pulls the vacuum down enough for those systems. If Dockhead just wants to go out and BUY what he needs, new and not trolling around for used...It won't be $85, will it?
Amazon.com: Robinair 15115 VacuMaster 1.5 CFM Single Stage Pump: Automotive
__________________
accomplice is offline   Reply With Quote
Old 05-09-2014, 14:05   #26
Registered User

Join Date: Jul 2012
Boat: Tayana 58 DS
Posts: 661
Re: Basic Boat Refrigeration DIY

Quote:
Also Bad advice to leak test with 250 psi of nitrogen as it can destroy Roll-bond thin plate aluminum evaporators. One hundred and fifty psi should be maximum test pressure and even then on older evaporators pressures above normal conditions may open weak spot pin holes common on units more than 10 years old.
Mine was (is) a holding plate system with R-404a. At 90F is 204psi, at 105F is 253psi. I greatly respect your knowledge and experience, and 250psi might not be the right pressure test in OP's case (R-134a, evaporator plates), but in mine it was.
__________________
accomplice is offline   Reply With Quote
Old 05-09-2014, 14:08   #27
Registered User

Join Date: Apr 2013
Location: So Cal
Boat: Catalina 30
Posts: 943
Re: Basic Boat Refrigeration DIY

I got my cheapie Harbor Freight 2.5cfm pump for something like $59. I've only used it on automotive applications thus far (as the fridge in the boat seems to work just fine)
__________________
jeepbluetj is offline   Reply With Quote
Old 05-09-2014, 14:33   #28
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Cowes (Winter), Baltic (Summer) (the boat!); somewhere in the air (me!)
Boat: Cutter-Rigged Moody 54
Posts: 19,737
Re: Basic Boat Refrigeration DIY

Quote:
Originally Posted by typhoon View Post
Dockhead, what do you mean by "self-pumping" . Are they water cooled ?

Regards .
Yes, they are passive water cooled -- the condenser is a loop formed inside a special through-hull. The motion of the boat "self pumps" water over the condenser. It seems to work extremely well, although I guess my cruising grounds -- where the water temp is rarely over 20C -- is not the harshest test.
__________________
Dockhead is offline   Reply With Quote
Old 06-09-2014, 11:26   #29
Registered User
 
typhoon's Avatar

Join Date: Feb 2007
Location: Toronto Canada
Boat: Bristol 45.5
Posts: 945
Images: 1
Re: Basic Boat Refrigeration DIY

Quote:
Originally Posted by Dockhead View Post
Yes, they are passive water cooled -- the condenser is a loop formed inside a special through-hull. The motion of the boat "self pumps" water over the condenser. It seems to work extremely well, although I guess my cruising grounds -- where the water temp is rarely over 20C -- is not the harshest test.
O yes I remember that set up , I always thought it was a good idea, but i agree, water cooling my be over kill , you are probably just fine in your area with air cooling. I actually intend to air cool even in the tropics , just making sure the fans have a fresh air source .

I know there were issues with any "O" rings in many water cooled systems , do you have them in your setup? Maybe a source for leaks .

Regards
__________________

__________________
typhoon is offline   Reply With Quote
Reply

Tags
refrigeration

Thread Tools
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
Don't Replace Refrigeration - Low-Cost DIY Repairs Richard Kollmann Plumbing Systems and Fixtures 3 03-06-2010 17:25
DIY Basic Outboard Repairs s/vAngel Auxiliary Equipment & Dinghy 13 17-04-2009 07:53
WANTED: BASIC BOAT BBQ. CHARCOAL IS OKAY, BEATUP IS OKAY, ANY BOAT BBQ - $25 seattle stephenronning Monohull Sailboats 0 29-03-2009 22:19
DIY Boat Refrigeration Book - Kollmann markpj23 Classifieds Archive 1 06-09-2008 11:59
RPARTS DIY Refrigeration kit Celestialsailor Plumbing Systems and Fixtures 16 06-03-2008 12:21



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 21:21.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.