Fridge Died - Isotherm with Danfoss BD35F

[night0wl]

Sailnet -

So, our fridge too has died. Came onto the boat this morning and did my customary checks...including checking the voltage on the batteries. Noticed they were exceptionally high, a full charge!!!

That never happens because the fridge is always sucking down the amps, and my readings are usually in the 12.5-12.8 range.

So I immediately flip off the breaker for the fridge and then back on. Nothing...the voltage stays high and I dont hear the fridge compressor run. So I go check the fridge. Sure enough, all of my BEvERages are warm and there is moldy smell now in the compartment.

Immediately, I start taking things apart. The fridge is now out of the cabinet for which I had to cut the power wires to it because you cant reach to the right side of the fridge to disconnect. Great design Beneteau/Isotherm

I have a spare battery hooked up to the fridge via alligator clips and here is what I've found:

1) The fan (not compressor) on the back of the compressor runs just fine
2) The thermostat is not "clicking" at any point in the turning radius
3) The compressor will occasionally try to start then immediately stop. It shudders for no more than 1 second

Any advice on what to do next? I want to test the thermostat, but have no idea on how to "jump" the thermostat to see how it would work without it. Any advice?

Here is a pic of my controller for the compressor...what wires should I "jump" to bypass the thermostat?

Thanks all.

--night0wl

[night0wl]

Ok - here is what I've tried again.

I think I've been able to "jump" the thermostat...and it results in the same thing. The compressor shudders for 1 second then dies again. The fan in the back keeps humming along just fine. WHAT GIVES!?? I dont have an diagnostic LED handy but I think this may be my next step...to wire one into the system to give me more data on whats wrong.

See below for what I did to "jump" the thermostat...is that RIGHT??? Its in red on the 101N0210 module.

[night0wl]

Ok ...now I've wired in a diagnostic LED. It returns 3 flashing. From another forum, this is what it means:

Three LED flashes indicate excessive torque is required to start compressor. This is commonly caused by turning compressor off and back on too quickly or too much refrigerant or poor condenser cooling. Most people jump to the conclusion that there is a mechanical rotor lock up inside compressor and this is a mistake on Danfoss BD compressors.

Now what???

Youtube video of the jury rigged setup:***VIDEO TAKEN PRIVATE...PM me for link*** (I dont want to bring bad press to a company thats coming through for support)

[deniseO30]

Danfoss BD 150 compressor. is a permanent magnet brushless DC motor, hermetically sealed. I would not guess the mags are external.

Ahem.. sounds like bad news; won't start, it tries and and tries. "locked" means the motor can't turn the crankshaft or the motor's start winding or start componants have failed.

[night0wl]

Originally Posted by deniseO30

Danfoss BD 150 compressor. is a permanent magnet brushless DC motor, hermetically sealed. I would not guess the mags are external.

Ahem.. sounds like bad news; won't start, it tries and and tries. "locked" means the motor can't turn the crankshaft or the motor's start winding or start componants have failed.

Bummer...i was hoping there was a chance of salvaging this.

I looked up a few sites on the 3 LED code, and I found that it *COULD* be a bad controller board. Thats a $250 part from Danfoss, but $150 on eBay. I'ver ordered the part from eBay and will try and effect repair as soon as it arrives. Any further advice on this?

Thanks!

[billyruffn]

I suggest you call the owner of Sea Frost. I think his name is Clive and he's the most knowledgeable person I've met on the subject of marine refer systems. Tel: 603) 868-5720. He's a straight up guy and will probably be willing to help you diagnose your problem. I bought one of his systems (which uses the same compressor you have) and it works very well. If your system is shot, I'd highly recommend Sea Frost as a replacement. They come with precharged compressor and plate, and can be installed by a reasonably competent DIYer (with some help from a friend).

[deniseO30]

Danfoss North America - Danfoss

[night0wl]

Guys -

Here is an update. Indel Webasto (Isotherm) are coming through so far. Turns out, I am or may still be under warranty, so they're offering to test and replace my control module gratis. Labor will still be me, but parts will be comped.

Lets see how this goes.

Also, Richard Kollman happens to be an UNBELIEVABLE resource for refrigeration. The forums are a wealth of info. Not to mention, he's a neighbor of mine...what were the odds!!

[night0wl]

Here is another update everyone.

Indel/Isotherm/Webasto came through *bigtime*.

Luckily, they're in Pompano Beach, FL and I'm in Fort Lauderdale. So, I dropped off my suspect Danfoss control unit and they swapped it with a tested/functional unit.

Later that night, I mounted the unit on my Isotherm fridge, hooked it up to the battery and *VOILA*....we have a happy compressor humming away quietly.

Turns out, this controller and compressor design is a bit suspect. The "cooling" fan for the entire unit is clear across the entire module, which prevents airflow from eventually reaching the controller module. On top of that, another design flaw is that hte module is VERY VERY heat senstive. Its got a massive 3 bladed copper heatsink that gets extremely hot I'm noticing. Danfoss really should beef up the fan or add a second fan to the unit to cool along the heatsink. For now, I'm likely going to vent my fridge cabinet and add another pc fan to the setup to circulate air better over the controller heatsink.

I'm not going to say I liked the overall experience (who does, stuff breaks way too often in the marine industry) but overall, I'm proud of what I was able to learn about my boat refrigeration and learned the value of having a spare for EVERYTHING.

Just in case this happens again (and I suspect it will)...I've ordered another controller off of ebay.

[deniseO30]

there you go! congrats! Just replaced the condenser on my YCs walk in box last week. Nearly the same price as a boat condenser, but about 10 times the capacity! 230 volt too

meaning; glad you did not have to lay out big bucks. "marine" equipment is so damn $$$