Problem with Adler-Barbour CU-85 Power Consumption

[mcaswell]

Our boat came equipped with an Adler-Barbour/Waeco Coolmatic CU-85. I do realize that not having enough insulation is a common problem with marine refrigerators, particularly icebox conversions like this one, causing them to run more often. But in this case, it seems like when it does run, it consumes what I believe to be an abnormally high amount of power. For a while when first turned on, it draws over 8 amps. Eventually, after running for a few hours, it settles down to about 6.5 amps. But according to the unit's data plate, it says that it should draw 45 watts, which should be in the neighborhood of 3.5 - 4 amps, right?

I also noticed that after it's been running continuously for a while, the compressor gets quite hot... hot enough so that I cannot keep my hand on it for more than about 5 seconds. Is that normal?

It does cool well though.

--Michael

 

[Stu Jackson]

A/B current consumption

1. How old is the unit?

2. Is the fan running? I have had to replace the fan three times in the last ten years on our unit. The least expensive replacement that works is a 4 inch computer fan from Radio Shack, compared to $43 from the fridge repairman.

I read 4.9 amps on our Link 2000, most folks use 5 amps running with a 50% duty cycle for 60 ah per day for energy budget use. It will run longer upon first startup when the box is not yet cooled.

You might want to consider calling Waeco Adler Barbour - Google to find them, I don't have their # handy, talk to Gary, a good helpful fellow.

 

[mcaswell]

Stu,

I'm not sure how old it is. The boat is a 1997, but I believe the refrigerator was installed some time after that... the unit does look pretty clean though, and if I had to guess I'd say it's 5 years old.

The fan is indeed running.

I just called a local repair tech who specializes in marine refrigeration, and he's going to talk to AB today to see if they have any insight.

--Michael

 

[tsmwebb]

The unit comes with a compressor speed adjustment. When used as a freezer (or with a really leaky box, I suppose) it is run at it's highest speed and 7~8 amps doesn't seem out of line. Given the age of your unit I'd suspect the compressor speed is set by moving jumpers on the back of the controller unit. The box is most efficient when it runs at the lowest possible compressor speed that will keep the box at the desired temp at 100% duty cycle. So, your goal is to set the compressor to run at the slowest practical speed. You can't really set it to run 100% duty as it will not be able to cool the box down when you load it. However, I'd suggest experimenting with setting the compressor to a lower speed.

Also, if you are running a freezer, I'd suggest setting the thermostat to keep it frozen but not "deep" frozen -- eg. ~20 to 10F rather than 0 to -20F of your home freezer. The thermostats are adjustable so, if you have a freezer thermostat and at "1" it is too cold, you can modify the switching temp. The adjustment isn't really intended for DYI but it isn't rocket science either...

--Tom.

 

[mcaswell]

Thanks, Tom... very helpful. I'll check that.

--Michael

 

[Ron20324]

I don't know your compressor location, but assume it is under the countertop, probably a cubby next to the icebox itself? My arrangement has a partial divider between them, so hot air can drift under the divider thus warming the icebox. Stuff it with insulation or some other way to block it off. There already was a vent on the forward side of the cabinet, but down low and not real effective since heat rises. I added a second vent as high as I could on the aft side of the cabinet. I can really feel the heat drifting out of the new cross-ventilation vent. It would help heat a cool salon. Underway, cool air blows in the front, heated air out the back.

 

[mcaswell]

Ron,

There's a bit of distance between the compressor and icebox. The galley is U-shaped, with the icebox on one side of the U, and the compressor on the other side (in the cabinet below the sink).

I think I will add some vents.

--Michael

 

[Ctskip]

As for the heat question. Isn't there a water cooling accessory you can purchase for that model ? I bought one for mine and it made all the difference in the world as far as heat goes.

Keep it up,
Ctskip

 

[mcaswell]

Well, I looked through the manual for the ColdMachine, and wow... this installation is pretty bad compared to what AB recommends (well, mandates actually) in the manual. I really don't think this is directly related to my power usage problem (it happens even if the cabinet door is open, and it happens right when the unit is turned on and before any heat would have a chance to build up around the compressor anyway).

But still, this is something I'm going to have to address, as it surely is not allowing it to cool as well as it could.

I'd really like to find some way to ventilate this hot air outside the cabin... in 90+ degree summer days, the last thing we need is a cabin heater!

--Michael

 

[Ron20324]

I saw an installation where the compressor had a factory box fan, maybe 4 inches square? The owner got a square-to-round PVC or maybe downspout adapter and attached ducting to vent the hot air elsewhere. Remember, if you blow it out, you gotta have new air come in- sort of like a bathroom fan. All parts were from the hardware store.

 

[mcaswell]

That sounds like what I'd like to do... add some vents to the cabinet for incoming air, but routing the warm air out of the cabin somehow.

--Michael

 

[Larry14133]

Wiring

I'd check the wire size and connections. If the wire is undersized for the load or you have bad connections the Current is going to go up. Noticed mine was draining a battery faster than normal and it ended up being a dirty battery terminal.

Larry

 

[mcaswell]

Service tech met me at the boat today... the problem was that the system was overcharged. He showed me on the gauge where it was supposed to be in the range of 9 - 12 (don't know what units are used), but it was about 22. He removed some of the refrigerant, and then the draw was 6 amps when it was first turned on, dropping to under 5.5 after just a few minutes (again, before it was around 8 amps at first, eventually dropping to 6.5 after several hours).

He said the draw would likely continue to drop a bit more once the box cooled off.

So, that problem is apparently solved, but I still need to address the lack of ventilation.

--Michael