Alder Barbour Refrigeration

[ScottFreeRick]

I have a Hunter 34 set up with a 276 ah #2 bank. This season we added 350 watts of solar which is connected only to the #2 bank. All battery wiring through to the DC panel and A-B Cold Machine has been replaced. Our #1 bank is a single 72 ah battery used for starting and our windlass.

The fridge / freezer unit works fine during the night hours. We recently started to hear a beep type sound in the early afternoon when the compressor attempts to start. It then cycles every 45 seconds, attempting to start, but fails. When this happens the solar is cranking 14v + into the batteries. As a note, we have also seen this happen, on occasion, when using the AC charger (pre solar installation).

Once the failure occurs, I have found certain things that will allow the A-B to start.
1. I can turn on blower, pumps that will put a load on the #2 bank, and the Cold Machine will start. However, the Cold Machine fails to start again on the next cycle.
2. If I switch to the #1 bank, the unit will start and will continue to run. It is a problem, since on one occasion I forgot to switch it back.
3. When I was using the AC charger prior to installing the solar, I could turn off the charger and it worked fine.

The symptoms indicate the problem is a voltage drop, but it only happens when an AC or solar charge is being applied to the #2 battery bank. I have been chasing this around for a while now. At this point I need some fresh eyes and ideas to explore.

 

[jviss]

The symptoms indicate the problem is a voltage drop

From my reading it's that the voltage is too high! 'Though, I know that doesn't make much sense.

Most A-B controllers have a diag port that puts out beep codes with diag info. You need to get an LED and connect it, and then read the codes.

 

[JoeWhite]

Just guessing, start from the 1-2-ALL switch, remove the lugs and clean them and continue down the circuit including battery terminals including negative terminal. Since it works with the other battery, I can think that it must be the supply source. Are bank 2 batteries getting old?

 

[jssailem]

Hi. I like to start at the manual. Attached find a link to the manual. Also I have selected the electrical connection pages.
Reading these leads me to examine the power source you have. The start cycle needs to get 10 amps at greater than 11 volts from a stable electrical DC source.
The write up of your experiences/inspections leads me to question if that is being provided to the controller. The suspects: 2 battery banks, the wiring sizes, the other loads on the system, the connections of wires involved.
That is where I would begin my testing.

https://epi.dometic.com/externalassets/cu-100-air-cooled-coldmachine-12-24v-dc-_9108777973_62743.pdf?ref=-655570134

 

[ScottFreeRick]

jviss - I had considered that, but the manual indicates that it should work up to 15 volts. I don't recall seeing a diagnostic port on the cold machine module, but I will check when I get back to the boat tomorrow. What would you use for an LED?

Joe - the batteries in #2 bank were new last year. All the wiring was replaced and cleaned up from the batteries, through the master switch to the DC panel.

jssailem - thanks for the pdf and links. I will review these this evening, although at a quick glance, they look different than the old manual which I have. I have checked the voltage at the controller and it shows a slight dip when the compressor attempts to start, but still close to 14 volts (on a digital meter). As I mentioned earlier, I can turn on blowers and pumps, loading up the system with 10 - 15 amps. The compressor will start on the next attempt.

Since the load on the system will lower the voltage slightly, it almost seems like the voltage is too high as jviss suggested.

Thanks so much for the input and resources as it gives me some new things to check when I get back to the boat tomorrow.

 

[jviss]

jviss - I had considered that, but the manual indicates that it should work up to 15 volts. I don't recall seeing a diagnostic port on the cold machine module, but I will check when I get back to the boat tomorrow. What would you use for an LED?

Joe - the batteries in #2 bank were new last year. All the wiring was replaced and cleaned up from the batteries, through the master switch to the DC panel.

jssailem - thanks for the pdf and links. I will review these this evening, although at a quick glance, they look different than the old manual which I have. I have checked the voltage at the controller and it shows a slight dip when the compressor attempts to start, but still close to 14 volts (on a digital meter). As I mentioned earlier, I can turn on blowers and pumps, loading up the system with 10 - 15 amps. The compressor will start on the next attempt.

Since the load on the system will lower the voltage slightly, it almost seems like the voltage is too high as jviss suggested.

Thanks so much for the input and resources as it gives me some new things to check when I get back to the boat tomorrow.

What's the model number of your controller?

 

[ScottFreeRick]

Will have to check model tomorrow when back to boat

 

[ScottFreeRick]

Model #: Danfoss 102N3030
Currently working on the possibility of voltage being too high. Put the solar in custom mode today and lowered the voltage settings.

 

[IllusionV]

Hello all...

I am having an similar issue with my Danfoss Refrigerator Controller (Model 102N3030).

Works perfectly "most" of the time (the model that runs on 12VDC off of the battery system). Occasionally, when the battery charger is running at the slip and when batteries fully charged, the compressor will turn ON and then OFF with one accompanying "BEEP". Over time the fridge will no longer be cooled.

This will continue until the Charger is turned "OFF" and the battery will then have a reduced voltage. The Fridge is cycled OFF then ON and will then operate normally.

I also suspect something to do with the high Float Voltage (have seen on Danfoss site that a resistor can be installed between the C an P Terminals on some controllers, but the unit I have does not have a "P" terminal).

I don't want to have to replace with the current unit that has 120VAC and 12VDC auto-sensing if a "fix" is out there...

David Roberts
MIRAGE 33

 

[ScottFreeRick]

David , your description is very similar to what I am seeing on my boat. The unit is able to cool properly and temperatures in both the fridge and freezer part are good. I did explore the high voltage concern when charging, but now I am back to thinking this is a voltage drop on my house bank. It has 3 group 27 AGM batteries and I have been investigating how to balance both the charging and loads across the batteries. We are living on the boat this summer and have been able to "manage" the fridge. Overnight with no solar and the AC charger turned off, we are able to use the house bank without problems. During the day, when we begin to encounter the "beep" and compressor not starting, we switch over to the single battery on the #1 bank. On this bank, I have never had a time that the compressor would not start.

I am still troubleshooting the issue, and if I am able to resolve it, I will post my findings.

 

[Hayden Watson]

Hello all...
...
I also suspect something to do with the high Float Voltage (have seen on Danfoss site that a resistor can be installed between the C an P Terminals on some controllers, but the unit I have does not have a "P" terminal).

I don't want to have to replace with the current unit that has 120VAC and 12VDC auto-sensing if a "fix" is out there...

David Roberts
MIRAGE 33

Adding a resistor to the P or T termina is how you control the speed of the compressor. 0-ohm gives the lowest speed of 2000rpm. 1500-ohm gives the highest speed of 3500rpm. High speed creates more cooling at more total Ah consumed. slower speed gives less total cooling, but as reduced total Ah used. The best system is one that runs as slow as possible while still maintaining the desired temperature.

 

[Hayden Watson]

According to the AB manual that John linked to, there is over-voltage protection, but it is at 17v. It is possible that your charge controller is sensing the voltage at the battery at 14v but due to high resistance in your wiring, the voltage at the charge controller is much higher to overcome the voltage drop. I would suggest, testing the voltage at the +/- terminals of the AB when you are getting this no-start.

 

[IllusionV]

Adding a resistor to the P or T termina is how you control the speed of the compressor. 0-ohm gives the lowest speed of 2000rpm. 1500-ohm gives the highest speed of 3500rpm. High speed creates more cooling at more total Ah consumed. slower speed gives less total cooling, but as reduced total Ah used. The best system is one that runs as slow as possible while still maintaining the desired temperature.

attached is the document for a similar controller from Danfoss where is discusses the resistor for the Battery Protection setting (fig. 4 between terminals C and P) for the Compressor Fan settings can be adjusted with a resistor between Terminals C and T, but as mentioned, the version of the controller that I have does not have these terminals available.

 

[jviss]

The best system is one that runs as slow as possible while still maintaining the desired temperature.

Yes! It turns out that just like boilers, long burns are better than short burns.

 

[Hayden Watson]

attached is the document for a similar controller from Danfoss where is discusses the resistor for the Battery Protection setting (fig. 4 between terminals C and P) for the Compressor Fan settings can be adjusted with a resistor between Terminals C and T, but as mentioned, the version of the controller that I have does not have these terminals available.

If your AB is the same as mine, there is a silver box that the connections are made to and the thermostat is connected with a old fashioned phone jack. That jack is connected to 4-wires.
Red = 12v+
Black = 12v-
Yellow = T
Green = C.
I used this plug to connect my digital thermostat which gives me better control of the temperature and much lower Ah consumed on a 24-hr average.

If you look behind the silver AB controller, you will find a normal Danfoss/Secop black controller. If the silver box fails, the easiest way to get the system running is to remove it and connect directly to the black controller. The silver really doesn't do anything special.

 

[ScottFreeRick]

I have finally got the system working. As of this moment it has been running for 5 days straight. Solar charging using the automatic settings, and today I tested it with the AC charger on. Earlier this month, I decided to rewire the #2 bank in order to balance both the load and the charging on this 3 battery system. This did not solve the problem. Near wits end, I decided to remove the control module, cleaned all the contacts and, replaced connectors on the thermostat and fan wiring. When I put it back together, it would only beep and not start at all. This led to 5 days hauling ice and an unhappy crew, as we were planning to be out on anchor the following week.

I could not imagine what I could have done that it failed to start now. I once again removed the module, this time disconnecting the compressor as well. Took readings on the compressor, all good. The spade connectors, for the compressor, were slightly loose on the board. I removed these and squuezed so the connections were tight. Also, a close check of the 15 amp automotive type fuse appeared to have some corrosion under the plastic. I had one on board, so i installed a new fuse. I suspect the fuse was the culprit, since I had it out the first time and cleaned the contacts on it.

Well, since I re-assembled the unit, it has not missed a beat. We spent most of the last week on anchor and I am pleased to say both the crew and I are very happy to have this annoying issue behind us.

Thanks for all the responses and input.

 

[baycloud]

Glad it's working.

I have an AB cold machine from 1993. A few weeks ago, I noticed it wouldn't start. Haven't seen that issue before. But now it randomly seems to work with no issues. I believe that it's only a matter of time...

 

[Hayden Watson]

Glad it's working.

I have an AB cold machine from 1993. A few weeks ago, I noticed it wouldn't start. Haven't seen that issue before. But now it randomly seems to work with no issues. I believe that it's only a matter of time...

Like SFR did, go through every connection and make sure that they are all bright and tight. Low voltage is the most common source of trouble and bad connections are the normal culprit.