Danfoss BD35/Frigoboat problem

[hoaga]

Hello,
Our Frigoboat refrigeration system stopped working, and I could use some help.
Basically the danfoss compressor stopped and wont re-start. compressor is a BD35F (with Frigomatic K35F sticker as well). The controller is a 101N0320. The system is keel cooled, and the compressor and evaporator plate were replaced about 33 months ago in North Carolina. The system has been in use continually since then as we are full time cruising (presently just arrived in Malaysia). It just stopped out of the blue. It only gets switched off occasionally when we are getting SSB interference.

I've put a voltmeter on the terminals on the controller and the voltage drops from 13.2 to 12.6 when the compressor tries to start and fails. I'm using a Fluke meter to measure... I've jumped an LED across the small + terminal and the D terminal. I get three flashes. so, I'm trying to figure out what to do next!

There have been no recent changes to the system. Though I did install al Lithium battery system May of 2013. And had a new zealand technician add a little refrigerant also in May of 2013. I am suspecting the following:
1. failing controller due to over heating. The unit is in a closed space with no fan. And its hot here! And the water is very warm too Mid to high 80's and we've seen 93 degree water recently. And maybe the "35" compressor is too small for my fridge which is fairly big. When we replaced the compressor in North Carolina, the technician thought I should probably have a "50" but we put in another 35 because its what we were replacing.
2. Something in the system. I don't think the system has too much refrigerant. The keel cooler was not replaced when the compressor and evaporation plate were replaced. But it was replaced about 6 months before the last failure because there seemed to be a lot of electrolytic erosion of the keel cooler. So I replaced it with a used one from a friend--and we fixed the source of electrolysis. When the compressor was last replaced it was running but we were not getting cooling. And after we replaced it, the system took a pretty good long time to cool down the fridge at first, but it holds it down when once cool. I had always thought it was a little low on refrigerant, because we've never seen 100% frosting. Which is why we added refrigerant in NZ--and the cooling rate improved after this, but still not 100% frosting of the evaporator plate. But, the North Carolina installer thought it might have been possible that there was some issue with the crud in the keel cooler. But the system has really worked pretty well for the last couple of years--and our energy consumption has seemed good.
3. I've also suspected that we didn't need to replace the compressor in NC!! I'm more educated about the system now...

So, the question is, what testing can/should I do now to figure this out, and get parts ordered if necessary?

thanks,
Arthur
s/v Morning Glory

[GordMay]

Lets hope Richard Kollmann http://www.cruisersforum.com/forums/...lmann-831.html chimes in with his expertise.

Evidently, 3 blinks indicates a motor start error.
The rotor is blocked or I pressure in the refrigeration system is too
high. More than 73 psi (5 bar)
See ➥ http://www.isotherm-parts.com/PDF/se...leshooting.pdf

[Richard Kollmann]

Arthur, Of all the small Systems Frigoboat’s Keel Cooler units are the most difficult to troubleshoot do to their unconventional design. Three LED trouble code can mean an overload at compressor or an electrical problem such as a poor ground. Anytime refrigerant was tampered with I would first suspect too much refrigerant. History of unit sounds like refrigerant volume has increased do to rise in ambient temperatures. A simple non destructive test to reduce volume of refrigerant/ Pressure is to cool system down for one hour by placing ice up against evaporator and a zip lock bag of ice on compressor. This will condense much of refrigerant into a lower temperature liquid allowing compressor to start and run. Once compressor is running it will perform normal although still to much refrigerant will cause frost to form on return line to compressor. All other systems are less exposed to this problem because their refrigerant volume is less critical.

Moisture in system is another problem with this system do to location of location and size of filter/dryer. To confirm moisture in refrigerant or eliminate it as a cause of compressor not starting, Begin with a completely warm system and turn unit on while listening inside refrigerator or watching ammeter if so equipped. If compressor runs for several minutes and then stops moisture is generally the cause. If it is moisture it will freeze and thaw allowing some cooling of evaporator on any system that contains the correct amount of refrigerant. Unfortunately Frigoboat’s keel cooler refrigerant capacity is not sufficient to hold excess liquid in warm climates.

I do not want to get into the refrigerant flow problems that have not been taken care of easily in many of these Frigoboat units. You must first pin down the reason for high amperage overload Code of three LED flashes and it is not going to be a BAD COMPRESSOR.

The last non destructive test I can recommend is connect a fully charged battery totally independent of all boats wiring direct to Control module + and – terminals.

And Yes it is possible the module is bad but this is much less likely than a refrigerant problem, although another module should be tried before any destructive work is accomplished..

[hoaga]

Dear Richard,
Thank you very much for the informative post--but the beer is still warm!
I've now tried your suggestions with the following results:
1. I've placed the ice packs as suggested and it had no effect. The compressor tries to start but doesn't, and I get 3 flashes on the led.
2. I've directly connected full batteries to the + and - terminals with no effect. I'm using 6 gauge tinned wire with bolt on connections. The compressor tries to start, but doesn't, and I get 3 led flashes. I also measured the voltage drop with my fluke meter. It drops from 13.43 to 13.2 when the compressor tries to start. Through the normal wiring its 13.2 and drops to about 12.6 when it tries to start.
3. I haven't tried my clamp-on ammeter since the compressor doesn't run at all. Should I try this anyway?

What would you suggest to test/try at this stage? Try a new controller maybe? If so, any ideas on who would be a good source for shipping to Malaysia? I'm sure I can find a source but ideas would be useful .

Thanks again for your help. It is very much appreciated!!

--Arthur
s/v Morning Glory

[Richard Kollmann]

It is important that I understand your complete Frigoboat refrigeration system. I assume system does not have any of their add on gadgets like SSC or Merlin speed controllers and an electronic thermostat. I also assume refrigeration is not powered by any thing other than boat’s battery bank. I also assume there is no wire connected to Module F terminal.

Unless you have an oscilloscope you can not detect a voltage spike that the module might see preventing a full start up cycle of compressor. A volt meter will not detect voltage drop if there is no amperage passing through control module. Low voltage spikes in this start up cycle can be traced to any number of items in boats wiring, this is why I require the complete boats wiring to be bypassed first. Three boaters failed to follow this boat wiring bypass test and replaced complete refrigeration system to find the new system would also not run off the boats DC power grid.

One non destructive test I failed to list was to try a soft 2000 Rpm start up of compressor. The BD35 is a variable speed compressor and at this point it may be set up to run at a high speed. To insure compressor is running at its lowest speed turn power off to system. Then remove wires connected to module terminals C and T. Place a jumper wire across C and T terminals, this eliminates any resistance in thermostat and wiring effecting compressor’s speed. If compressor now runs it will be at a fixed speed of 2000 Rpm. Let compressor run until box temperature reaches desired box temperature. If you are unable to get compressor to run now I think a different module is required before tampering with refrigerant or refrigerant flow.

There are systems like Glacier Bay’s 12 volt and Frigoboat’s Keel Cooler models that require a very experience engineer close in to the manufacturers repair shops people if one expects a successful repair outcome.

If your mailing address were in USA I could sell or test your module but I will not try any more to export outside the US. My modules are guaranteed to operate any unit and if it does not satisfy you it can be returned within 30 days for full refund even if my module is damaged by your system. Because your need is for a current Model 101N0210 Danfoss standard module it should be available all over the world.

Status at this time:

Cooling down Refrigerant in order to reduce starting pressure was not successful.

Wired unit direct to a fully charges battery proved it is not a boat problem.

Guaranteeing a 2000 Rpm soft start ?

Trying another module or having present module tested on another unit, this would be the last non destructive test I can suggest..

If it is not the module causing a failure to complete compressor start cycle then it must be a refrigerant problem of too much or contaminated refrigerant. Too much refrigerant can be corrected by removing a small amount of refrigerant. See my web site Refrigerant charge section Too Much refrigerant at http://www.kollmann-marine.com. Contaminated refrigerant caused either by earlier tampering with refrigerant letting non condensable air in or a much bigger Frigoboat problem of capillary tube blockage possibly caused by poor compressor cooling in tropical climates. This compressor will run when low on refrigerant but it will not run if the is too much. It will not run if refrigerant flow is blocked by restrictions in capillary tube. The answer to restrictions on Frigoboat keel cooler systems many times is complete system replacement.

ANSWER QUESTION #3 An ammeter will confirm what the problem is only if compressor will run.

[hoaga]

Thanks again Richard!
I didn't mention before that the thermostat is a Coastal Climate Control that replaced the original at the time I last replaced the compressor and evaporator plate -- just shy of 3 years ago in North Carolina. My wife also reminded me that the keel cooler is the original, and I never replaced it. The one I replaced is on the freezer.
There are not other add ons or gadgets.
Just Keel cooler, evaporator plate, compressor with controller, and Coast thermostat.
The refrigerator is just wired through breakers to the house 12v system
There is nothing connected to the F terminal on the control box.
I'll try the 2000rpm restart next.
And if that fails I'll try letting out a little coolant.
As to the controller my controller is an 101N0320 not a 101N0210. Does that make a difference? Also, I had not thought about trying the controller from my freezer because it is different. The freezer has a 101N0210 -- but it is also connected to an SSC. Perhaps I can disconnect it, and give it a short before ordering anything new...

As to heat in the tropics -- the compressor is in a closed cabinet, so it doesn't get much ventilation. The ambient temperature here is typically in the 80's. But the water temperature is warmer than most places in the tropics. Water is often in the high 80's and even low 90's. Though when the unit quit working, the water temp was about 84.

thanks again,
Arthur

[hoaga]

Back with more data....
This is starting to not look good!
1. I swapped the controller with the one from my freezer. No luck, same symptoms. Compressor tries to start and wobbles a little as evidence then 3 LED Flashes. I put that controller back on my freezer and freezer continues to work.
2. I tried to let out a little refrigerant, per the instructions you passed along. Unfortunately, no effect. Perhaps it is notable that I didn't hear any refrigerant come out. I held it for three seconds (i used an allen wrench to poke the little thing in as far as it would go -- but gently of course). I didn't hear anything. I tried to start the compressor, no luck, same 3 led flashes. I tried again to let out a little refrigerant -- trying for about 2 seconds. Also not effect.

Sigh..... I hope to be able to find a decent refrigeration expert in about a week. Any ideas before then? Or am I at the stage of replacing the big stuff.... And perhaps I should ask if you have any suggestions for things I ought to have a professional try before we start buying the 3 big parts -- keel cooler, compressor and evaporator. would it make any sense to start with one thing at a time ?

Thanks again for you're valuable help!!
I only wish I could make use of your services directly from your business.

All the best,
Arthur
s/v Morning Glory

[mayball]

Arthur,
I service boat refrigeration in Puerto Vallarta, Mexico. When our sea water temperature gets into the 80 degree range I get a lot of calls on Frigoboat keel cooler installations failing with the three flashes on the LED. It is my opinion that the keel cooler is not large enough for such warm water operation. The Band-Aid fix is to let a little refrigerant out, reducing the discharge pressure. You will then find that a part of the evaporator near the outlet will not frost, but it can get you by. I think the permanent fix is an additional keel cooler in series or some other additional condenser help.

[Richard Kollmann]

The Coastal Climate Control is a gadget Besides maybe being less energy efficient it can affect the 1 to 5 milliamp module control circuit across the C and T terminals. Removing the thermostat wires from C and T and replacing them with a jumper wire will eliminate Climate Control and its possible control over compressor’s possible increased speed.

Danfoss intended for the refrigeration to be connected direct to battery main busses and not through a branch circuit buss. I do not want to side track this troubleshooting with a low voltage spike because you eliminated it by bypassing all boats wiring already.

With nothing connected to F module terminal this circuit is not overloaded so it is eliminated also as a problem.

Warning do not try to remove refrigerant with compressor running as system may be in a vacuum and air will be drawn in.

You tried your other systems module and eliminated module as a cause for compressor not running.

At this point you have gone through all possible boat and system electrical causes once you remove thermostat control over possible compressor speed/amperage increase.

The 102N0320 module was an attempt to solve the RF radio noise on many boats but other than a noise filter it functions the same as the standard 101N0210 module. The SSC is also an add on gadget that would be bypassed with the CT jumper wire test.


After you eliminate gadgets with jumper across Cand T and compressor will not run, we are then left with a refrigerant problem Too Much? Or Refrigerant flow blockage problem? From experience others have had with Frigoboat units it is unlikely that buying an evaporator or keel cooler or compressor will solve a contaminated refrigerant problem. Your best hope is there is too much refrigerant or air mixed in refrigerant. If you can find a good refrigeration person with a vacuum pump I would have all vapor removed from system and add a very small amount of pure 134a refrigerant till pressure is out of a vacuum say 5 psi when not running (STATIC) . Then without adding any more refrigerant turn compressor ON. Compressor should run but not cool evaporator. With compressor running add more refrigerant slowly till suction pressure is at 8 psi if after a total of 15 minutes running time pressure is above 8 psi you may have added too much. If problem was pressure too high and after cleaning gas/air vapor out. Final fine tuning of refrigerant volume is done by confining frosted areas to within evaporator. See Frigoboat Website or mine on Refrigerant Charge.

Let’s hope you do not have a refrigerant flow problem but if compressor will not run with almost no refrigerant in above test then we will have to look in to phase two.
Although I have maybe 100 posts and e mails on Frigoboat keel cooler systems troubles I can only theorize to there major refrigerant flow problems. Right now I believe excessive compressor heat is changing pure refrigerant and oil to a dirty thick sludge.

[colemj]

Richard,

The 101N0320 is the shielded AEO Danfoss module. I don't know if that makes any difference here, but it is the module that automatically adjusts the compressor's speed. As far as I can tell, the RF noise filter only consists of an aluminum box around it.

Mark

[Richard Kollmann]

Colemj, You are correct the 320 is an AEO that automatically changes compressor speed along with having the RF aluminum shield. When Arthur's installed the AEO on system that would not start it did result in a soft start that is another advantage to the AEO in hot weather. Thanks for your help.

[hoaga]

Thanks again Richard.
I forgot to mention earlier that I had already tried jumping the thermostat terminals to remove the coastal thermostat from the picture. No luck with that either.

So I think the next step is the vacuum pump. And I would not be surprised if heat was the culprit! do you think having BD35 instead of a BD50 could contribute to this problem? As I mentioned before, the guy in North Carolina thought I should probably have a BD50 for our refrigerator box size...

In the mean time, I wanted to ask again about removing some refrigerant.
I tried this per the instructions on your website. And I didn't hear any noise at all when I depressed the valve "thing". So I wondered if I was actually letting any out. I'm depressing what I understand to be the valve that is kind of like the valve on a bicycle--where you would add refrigerant. It is at the end of a tube on the compressor itself and it is close to the control box. And its the only one with a screw off cap that isn't sealed on with what looks like a sort of shrink wrap.

Thanks again,
Arthur

[s/v Jedi]

When I have a start problem it normally is the ff'ing DC feed again. I since removed those little PCB's that Frigoboat ships with the units that allow multiple cables to connect to the + and - terminals. I make those connections elsewhere and have single wire with terminal on those connectors.

Also, when you connect a gauge set, you can equalize pressure when the compressor has failed to start. This should make it easier for it's next attempt. Like Richard described, I also lower compressor rpm to overcome the problem.

When I start my system after the boat has been in storage with all shut down, I first throw a big bag of ice into the box to pull the temp down. When that is done, I start the compressor. I don't even try to do it all with the compressor anymore.

You could still swap compressors…. if you trust the quick connect fittings. Mine always worked correctly but I always expect to loose the charge. I find it strange that you don't hear any refrigerant escaping when you open the valve…

[hoaga]

Not hearing any refrigerant escaping when I depressed the valve made me wonder if it was stuck in a state of vacuum somehow. The unit was off when I tried this, so it would not be due to being on the suction side while running. But I also didn't hear any noise at all, so I didn't hear anything flow in either direction...

I tried this twice. Once for about 3 seconds, and once for about 2 seconds.

Also, fyi, I don't have a guage set....

[s/v Jedi]

Originally Posted by hoaga

Not hearing any refrigerant escaping when I depressed the valve made me wonder if it was stuck in a state of vacuum somehow. The unit was off when I tried this, so it would not be due to being on the suction side while running. But I also didn't hear any noise at all, so I didn't hear anything flow in either direction...

I tried this twice. Once for about 3 seconds, and once for about 2 seconds.

Also, fyi, I don't have a guage set....

I would recommend to buy one. If you go out cruising I even recommend to buy a vacuum pump and some canisters refrigerant plus the puncture-valve for them. It's easy to learn how to use these, plus you can take the time needed to evacuate a system well etc. It should not cost much to get these items, under $250 total here in Panama. I got mine from Amazon.com though.