Refit Refrigeration (Mr. Kollman are you there?)

[BriRich]

Hi Folks

Been reading up. Am refiting my 1983 Cape North 43. I have a well insulated (needs work) split frig freezer. Existing system has 3! compressors: engine driven, 220V water cooled and what looks like a 12v under the sink. None of it is working since I bought the boat 3 months ago. Supposedly the engine compressor is working but there is a refrigerant leak There are 4 Grunert cold plates and so much piping it looks like...well there's a lot and looks like a mess.

The boat won't be connected to shore power. She will be in the tropics mostly in Palau at 7.5N and ocean temp mid 80's F. Ambient air mid 90's Plan is to spend weeks at a time several times a year cruising around Palau eventually do some extended cruising.

The box is about 12cf total.

I am planning on 400ah wet cell house bank

80 to 100amp alternator w/ external smart regulator, no AC genset and no battery charger

260W solar power

led lighting and some fans

my plan is to rip out the entire refer system and put in an aircooled Adler barbour CU 100 with A/B 100 series evaporator VD-152QC. If it can't handle the load will install foam blocks inside the box to reduce the volume/load. Would ideally like to have a freezer and refrig side by side overflow.

One option that I have read about is to keep the cold plates, run an engine compressor to drop the temperature and maintain with the 12v air cooled compressor.

It's a big investment so hoping I can get steered in the right direction.

Mesulang/Thanks

Brian

[Rhapsody-NS27]

This guy did a pretty good job replacing his:
http://www.cruisersforum.com/forums/...dge-76345.html

[Richard Kollmann]

Jason’s boat refrigerator box is a masterpiece of workmanship and smart insulation application. There are two categories of insulated boat refrigerators the type that is installed by a boat manufacturer intended for a week or two cruising and those intended for live aboard cruising.
Production boat manufactures generally use spray Polyurethane closed cell foam insulation without moisture barriers or radiation reflectors. Leaving an air space surrounding insulation will allow moisture that collects on insulation to dry up when refrigeration is turned off for several days. This insulation works well for years or until out gassing of cells over time occurs.
Live aboard boats and those that cruise in tropical waters have double the daily energy requirement of boats cruising in cool climates. When the difference between cabin temperature and insulation’s exterior exceeds 7 degrees F moisture in air will be collected on insulation’s exterior surface.

Jason was smart in selecting conventional refrigerator closed cell controlled density insulation, instead of open cell insulation intended for keeping heat in and cold out. I have seen open cell insulation collect so much water weight it ends up in the bilge.

[Richard Kollmann]

Brian, If you plan on remaining in warm climates with a 12 cu ft box , I would plan on keeping engine drive system operating. Twelve volt is not a good option and your present Boat’s DC power grid as it would be in adequate for a well insulated box over 6 cu ft.
Adding 12 volt AB would reduce engine daily run time and provide a boost to engine drive if needed.

My recommendation for you is to first go to my web site at http://www.kollmann-marine.com and watch the slide show.

Send me pictures of engine drive components..

After I understand your engine drive better I will want you to put refrigerant Florissant die and 2 pounds of correct refrigerant in system. You will also need a Black light to find leak, but do nothing till I respond to system pictures.

[BriRich]

My recommendation for you is to first go to my web site at http://www.kollmann-marine.com and watch the slide show.

Send me pictures of engine drive components..

After I understand your engine drive better I will want you to put refrigerant Florissant die and 2 pounds of correct refrigerant in system. You will also need a Black light to find leak, but do nothing till I respond to system pictures.[/QUOTE]

Thanks Richard

I live in Oman but am going to the Philippines tonight for a week to check and prioritize refit progress so timing is perfect. Should have photos and more info in 3 to 4 days.

Also have visited your website several weeks ago and watched the slide show...which is why I haven't pulled the trigger and started ripping out the old system...and why I am seeking your sage advice.

[BriRich]

Hi Richard

I just got back from the Philippines and took some pics of the refer system. From the pics you may be able to see why I want to rip it all out and start over. We had a AC mechanic take a look. He says the engine driven compressor is a York.

Here's pics of the engine

[BriRich]

Here's pics of the heat exchanger in the engine room.

[BriRich]

Here's pics of the unit in the wet locker. I am told this is a 220V compressor and heat exchanger.

[BriRich]

And then another compressor under the sink in the galley.

[BriRich]

Here's a view of the box. I know the side door is bad news and we will seal it. Also some pics of the refrigerant piping inside the box. Our thoughts now are to just keep the engine driven system and rip out everything else. The raw water and fresh water engine pumps are being rebuilt now. When they are installed the AC mechanic will come back to test the engine driven system.

[Richard Kollmann]

BriRich, At Latitude 7 and a 12 cu ft box it would be a mistake to remove engine drive system. As I stated before this size box even with new insulation would be difficult to refrigerate using 12 volt refrigeration.

You indicated four holding plates but only two pictured. One plate appears to have both systems connected to it while second picture looks like plate is only for engine drive system.

AC SYSTEM
The 220 volt AC system picture shows complete condenser/compressor system with the exception of water pump, expansion valves and plates. To test this AC system , I would turn it ON if it trips power fuse or breaker then compressor is possibly bad if compressor runs there is a refrigerant flow problem. If compressor does not blow fuse/breaker then there is an electrical problem before it reaches compressor, First check and reset high pressure switch.
If this compressor runs and there is no cooling system may have a refrigerant leak. If leak is in seawater condenser system is probably not worth repairing as water could have circulated completely through system.

ENGINE DRIVEN SYSTEM

The engine driven compressor is either a Tecumseh HG 1000 or a York both of these compressors were used on Ford cars and truck AC units in the 1969 through the seventies. York compressors are made of aluminum while Tecumseh are Cast Iorn. Rebuilt compressors are still available and newYork compressors are sold under the Climate Control name. In many cases these compressors are run too fast for refrigeration and should be operated at 1200 to 1500 rpm.
A simple test is to rotate center shaft of compressor clutch with the palm of your hand. If you can rotate shaft through one complete turn and then back and forth without a clanging sound compressor may be OK. Next check clutch bearing by turning outside V belt pulley. There are two wires going to compressor clutch a short ground and a 12 volt power wire. If there is power applied to clutch power wire it will energize pulley with a snap and pulley will then turn compressor crankshaft. In order for power to be available to clutch this power wire beginning at circuit breaker/Fuse will pass through thermostat or timer switch, a high pressure switch, a low pressure switch and maybe even the engine power switch. All these switches must be closed for compressor clutch to operate.

Holding plates need to be checked for internal and external leakage. If plate is bulged out like having a ball inside there may be a refrigerant leak inside. If eutectic solution has leaked out of plate it will sound tinny when tapped on just like tapping on an empty gas can. Hopefully all plates will look and sound good.

After you confirmed that compressor will rotate it may be necessary to connect power direct to clutch with drive belt installed slightly lose. Lose belt is important so it can slip if there is too much torque required during this test. Now start engine and see if compressor is noisy, run engine for only a short time.
After compressor and its electrical system is checked out it is time to check the refrigerant system using refrigerant gauges. As old as this system is it will have Freon R12 in it. If there is some refrigerant in system ½ pound or more static pressure (Compressor not running) will read much the same as ambient air temperature that day 70 degree F ( 21C ) will produce 70 psi. pressure in system.

The white painted items in pictures are not for AC 220 system they all belong to engine driven Grunert system.

I will not go any further now let as see how your evaluation goes with mechanical and electrical condition of engine driven system. Next step will be reconditioning, Leak testing, dehydration and maybe conversion to134a compatible oil and refrigerant.
Up to this point a decision can not be made as to whether repair or replacement is the right direction.

[BriRich]

Thanks Richard

Will pass all this on to the crew in the Philippines. We won't be able to run the engine until our pumps are back from service so may be a while before we can test the system.

[BriRich]

Richard this link shows the exact system on the boat. Clarifies things a lot for me anyway. Looks like we have the ED 150 accumulator / condensor based on the pics.

Grunert Engine Drive Manual

[Richard Kollmann]

I hope your crew follows the systematic approach I recommended and do not start taking things apart. This is a simple conventional refrigeration system and age has nothing to do with its longevity. What makes this system complicated are the electrical controls that engage and disengage compressor clutch’s magnetic coil. Further complicating the electrical is Gurnert’s electrical wiring box is compatible with many of their systems. With two refrigerator box controls your system may have two thermostats and two refrigerant line solenoids. It is possible there is a wind up timer and no thermostats. The reason for a large constant duty heavy relay in electrical box is when the box is used on large belt driven 12 volt systems. The high and low pressure switches are two items in electrical box that should not be by passed these are safety devices that protect compressor and explosive high pressures.

Grunert seawater condenses are affected by electrolysis and have a zinc installed on them that must be replaced frequently especially on boats connected to shore power or with generators. Condition of condenser will be tested before opening any part of refrigerant circuit. Type test for seawater condenser will be determined when pressure gauges are first connected to system.

Many of these systems are still operating after 30 years in service. With exception of compressor or clutch failures components on ED150 pallet are almost bullet proof. When Grunert first designed this type system using reciprocal compressors in the 1960s Compressor speeds were lower because older sailboat diesel engine cruising Rpm was low.
Compressor failures are common in these systems do to poor lubrication or liquid slugging. Pryor to 1995 wax free mineral oil and Freon R12 was the standard refrigerant in this system. Refrigerant and its oil must be miscible so oil will travel through complete system mixed together. Compressor is cooled by returning refrigerant mixture and as compressor becomes warm majority of oil will separate from refrigerant and remain in compressor.

The reason Tecumseh and York compressors fail in Holding Plate systems is they are designed to pump gas an not liquid. When compressor is OFF for a long time and holding plates are still cold most refrigerant and some oil will migrate into cold plates and remain there as condensed liquid until compressor clutch is energized again. Hopefully your system is designed to run only once a day. If compressor is started with high engine Rpm at any time there is a chance liquid refrigerant and oil stored in cold plates it will quickly return possibly damaging compressor.