Refrigeration startup and rehab

[Richard Kollmann]

Icemate, Hopefully you have not followed some of the advice so far given. Sorry my book did not cover your refrigeration problem but my web site would have. Technical books must be revised every year in order to justify their value. My method of book updates is to post revisions and typical repairs on my web site or forum.

Reading your comments thinking you have a BD35 compressor confuses me in that Adler Barbour changed from the BD3 to the BD50 compressor. All earlier BD 2 and BD2.5 compressors were designed for Freon R12 refrigerant. Use of 134a in these old compressors is not wise. You can tell the difference between old and the new variable speed BD 35 and BD50 compressors by type of control module and where it is mounted on condensing unit. The BD 35 and BD50 modules are fastened directly to compressor the other are mounted separate from compressor with a large power cord connected to compressors

If you have not tampered with refrigerant and now run compressor for 30 minutes the frost cover will determine condition of refrigerant charge The correct volume of refrigerant in your Adler Barbour system depending on what evaporator was installed,, 80 to 120 grams by weight ( 4.2 ounces). The small can of refrigerant contain 10 ounces by weight .

Remember This Is an Adler Barbour and not any other type unit .
The first thing you want to know is there adequate refrigerant in your system and how much. The answer to this question is after 30 minutes running is a thin layer of frost covering at least 85 % of evaporator’s surface area. The percentage of frost cover is the volume of refrigerant. Fifty percent of surface area covered would indicate loss of around two ounces of refrigerant. With compressor running and not stopped by thermostat there will always be a faint hissing sound in inside evaporator confirming gas vapors are moving through system without blockage.

Confirmation of gas flow and lack of cooling confirms problem is loss of condensable gas R12 or 134a depending on model of compressor. The next step is to determine the leak rate of refrigerant and look for leak area. The speed that refrigerant leak from this model system can help guide you to leak area. Finding a leak where all refrigerant is lost within a week is easily detected with my soap and water method. See My Web Site.

When refrigerant loss is faster when compressor is running keeping box cold with thermostat the problem leak is in high pressure side of system. Most likely a high pressure line connector leak Tightening that connector 1/8 of a turn can press metal to metal seal more and stop leak. You would confirm this leak by leak testing when compressor is running.

When refrigerant loss is slower when compressor is running and cycling on thermostat day after day leak is in low pressure side of system. Servicing fitting caps are not sealed tight. Return refrigerant line connector leaking. When loss of 50 % of refrigerant occurs over six weeks or longer there is a possible micro size hole in evaporator caused by interior or exterior corrosion. Once evaporator becomes porous the only fix is replacement.

Hopefully all your tools are still put away and you want to avoid wasting time with suggestions that most likely would not be wise mainly because you have an Adler Barbour system.

BOOK UPDATE web site on REFRIG GHARGING

Kollmann Marine

The above information is of little value if your system requires a regular charge of refrigerant. You will need one small can of the correct refrigerant for your system and servicing hose with a tap a can attached. If 134a is correct refrigerant an adapter to connect to Danfoss old style service fitting still used on AB systems.

There are several methods of how to get correct refrigerant charge:
• Add refrigerant slowly and stopping when ammeter reads 5 amps. Then fine tune by frost line
• Compressor not running Allow upright gas vapor can pressure not liquid to equalize pressure in system to can pressure. Then fine tune by frost line later.
• Use servicing gauges to reach the normal low pressure operating range of 6 to 10 psi. Do not adjust refrigerant volume by gauge pressure after evaporator is cold as the colder refrigerant flow control capillary tube is going to reduce gauge pressure to lower evaporator/box temperature.

[Dougtiff]

O.K., i just replaced my evaporator, because stupid me used a sharp tool to remove the built up ice [even thought i knew better] firstly i vacuumed the unit, san the new evaporator, then connected the evap, via the couplings and then charged the unit with a gauge set, so heres the thing, it takes VERY little gas, squirt a little in and wait for the system to equalize, you will hafto play with the charge till you get the correct amount of gas in the system, you can hear the gas going thru the evap, you only want frost on the evap, not further along toward the compressor. i think you are low on gas, possibly via the couplings, as this is not un-common over a long period of time, don't over complicate the issue and you don't need a teck with a recovery reciever, your just throwing away your money and anyway thesee guys dont work on stese small 12 volt dc systems anyway, thatsucker just needs some gas, you might hafto vacume first, if so do that and put a charge ib and watch the gauge to see if it is holding, hope this helps. p.s., ive been working on this stuff for years, self taught, used to build from scratch systems with holding plates, compressor, ect. great fun.

[Capt Gill]

Originally Posted by Richard Kollmann

Icemate, Hopefully you have not followed some of the advice so far given.
Hopefully all your tools are still put away and you want to avoid wasting time with suggestions that most likely would not be wise mainly because you have an Adler Barbour system.

There are several methods of how to get correct refrigerant charge:
• Add refrigerant slowly and stopping when ammeter reads 5 amps. Then fine tune by frost line
• Compressor not running Allow upright gas vapor can pressure not liquid to equalize pressure in system to can pressure. Then fine tune by frost line later.
• Use servicing gauges to reach the normal low pressure operating range of 6 to 10 psi. Do not adjust refrigerant volume by gauge pressure after evaporator is cold as the colder refrigerant flow control capillary tube is going to reduce gauge pressure to lower evaporator/box temperature.

This is excellent advice and Richard's book is in the same class as Nigel Calder's Boatowner's M & E Manual, however I found Richard's better when working on systems using the Danfoss hermetic internally sealed compressors, no disrespect to Calder,but for me the amount of detail obscures the main issues one usually encounters when having a problem. A little anecdote : A couple years ago my Frigoboat system (w/evap) was not cooling properly, not being up on the peculiarities of this system I had a tech look at it he did then charged the system, worked ok for a year then the problem reoccurred, this time I had purchased and received Richard's book, but didn't give much credence to the part about not really needing gages, etc., so I dove in and spent a lot of time tweaking this and that, still didn't get it quite right. Slept on it,then back to book this time not ignoring the SIMPLE stuff – no gauge, just can of R-134a and hose w/adapter, run system OBSERVE % of frost coverage on evap., add wee bit of R134, frost on return - no-a little sweat - ok ... Fixed ! KISS !
Later I showed the tech the book he asked if he could borrow it, later on I found out he made a copy, this angered me as Richard has given so much free advice to our boating community that the least he could do was BUY the damn book ! There's a huge difference between CHEAP and thrifty .

[sailah]

I totally agree. I'm cheap but own his book.

Thanks Richard. I'll review again and check out your updated website. I know I'm going to get this figured out thanks for everyone's help so far. Will probably be a couple weeks until I'm able to tackle

[sailah]

Just wanted to check back in on my own thread with a few questions:

After years of not having my refrigeration system running (ice!) I got it working with Richard's book and selective filtering of internet advice.

I thought I had a Danfoss BD35 as that's what survey stated. I think I likely have a Danfoss BD2.5 of BD3? In either case, when I vacuumed and refilled system , I used R134A with my gage set and Dupont Suva

I don't have a great picture other than this when I fixed the wiring issue. How can I tell the model? I understand the BD3 to be R134A while the BD2.5 was R12?

I've had the system running on land for the last few days and been monitoring actual box temps with some of my company's wireless temp monitors so I can do it from my office. Seeing ~34F in fridge about half way up box and 6-22F in freezer compartment depending on where compressor is in cooling cycle. It froze a water bottle in a few hours from startup.

I'm also getting a gurgling sound from evaporator plate area when running. Is this normal?

[icemate]

All compressor and cond. units have data plates on them. Unless someone removed it, look for plate oncond. unit base or compressor. This can then be researched online for all tech, data needed.
I sailed from Buffalo, NY to Australia and had only a small refrigeration unit but before departure I completely re-insulated my icebox (yes,icebox as there was no refrigeration and only a cooler to put ice in). Being in the refrigeration business I always felt that you can almost never have enough insulation. I reduced the size of the box by installing 4" Styrofoam not polystyrene. This included the lid. This made the box smaller but then never had a problem.
In New Zealand I did install solar panels and had two battery banks and a seperate battery for starting the engine. Energy conservation while cruising is the best thing you can do to enjoy. Saving Amps, save money.

[sailah]

Thx, yeah I can lower my camera into the area and try to get a model. Since adding 6V batteries, I've encroached on my ability to climb down in the cockpit locker where this is located hence the only pic I have. I didn't know if the controller number was a clue to the compressor model.

My insulation is adequate for my cruising needs now. I presume Dickerson did a decent job at the insulation but it's a 1986 boat. Certainly not enough for me to warrant tackling the job of adding more interior insulation even though I agree with you 100% that more is better.

Since I no longer use ice, I'm thinking of plugging up the drain hole to the bilge at bottom of refrig space.

[a64pilot]

The gurgling is normal, it’s likely the phase change from liquid to gas that your hearing and that of course is where the heat is absorbed.

I have an 87 model boat and yes the insulation has certainly deteriorated some. I too chose not to tear into the cabinetry to make a new box.

Plug the drain hole with a rubber stopper, this will help the freezer from icing so fast as less warm moist air will be pulled in, but for sure leave it so you can easily unplug so defrost and cleaning water can just go out the drain.