Changing out AB Cold Machine Fan

[zboss]

Hi,

I just cleaned the fins on my AB machine and I took note of the fan model. The fan uses 0.3 amps and moves 80 CFM of air.

As the fan is a standard dimensional 120 MM style, I was able to find another fan that drew 3 amps but moves 240 CFM. I am wondering if this would perform any better or not, or even if the AB board could supply that much current to the fan.

Maybe the fins won't allow CFM to move through them.

Has anyone experimented with upscaling the fan?

[mayball]

I think you will find that the AB board will not supply over one ampere and, therefore you would need to drive the fan through a relay. Many boaters would balk at a 3 amp fan load on a refrigerator which, itself normally draws only 5 amps.

[Richard Kollmann]

Originally Posted by zboss

Hi,

I just cleaned the fins on my AB machine and I took note of the fan model. The fan uses 0.3 amps and moves 80 CFM of air.

As the fan is a standard dimensional 120 MM style, I was able to find another fan that drew 3 amps but moves 240 CFM. I am wondering if this would perform any better or not, or even if the AB board could supply that much current to the fan.

Maybe the fins won't allow CFM to move through them.

Has anyone experimented with upscaling the fan?

On some models of AB the fan is mounted under the plastic shroud so rivets must be must be removed to get to the fan. If inside instead of outside shroud you are limited to the original one inch thick 50 Cfm fan.
I recommend a 12 volt model 4T-36 producing 107 Cfm, 1 1/2 inch thick fan from www.granger.com. around $30. This fan is rated at just over 1/2 amp. If your compressor is a BD2.5 or BD3 the fan circuit will handle fan amperage up to 1 amp. The BD 35 and BD50 module fan circuit is limited to 1/2 amp but on AB newer units there is an external stainless box for loads up to 5 amps for additional fans. It can handle fan amperage up to 1 amp. The BD 35 and BD50 module fan circuit is limited to 1/2 amp but on AB newer units there is an external stainless box for loads up to 5 amps intended for additional fans. I advise against the large 220 Cfm fan it is noisy and overkill even in a warm climate.

[zboss]

So I was changing out a circuit breaker this past weekend and I noticed that the wire going to the compressor was a bit warm... I measured it at 90 degrees using an IR thermometer. Is this normal? Could an old cable be the cause of the high amp draw?

- z

[Richard Kollmann]

Originally Posted by zboss

So I was changing out a circuit breaker this past weekend and I noticed that the wire going to the compressor was a bit warm... I measured it at 90 degrees using an IR thermometer. Is this normal? Could an old cable be the cause of the high amp draw?

- z

First I do not know how you would be able to read temperature of a wire carrying 5 to 6.5 amps with a IR temp meter.

If wire is actually warmer than ambient air with no other heat in area that could effect wire temperature you should consider wire size or a poor connection is causing heat generating anperage resistance and voltage drop.

Adler Barbour manual calls for a 15 amp Circuit breaker or Fuse. The wire size and its length must be able to handel more than 15 amps without heat/fire damage.

[zboss]

Well, I just pointed the laser at the wire sheath. The wire was noticeably warm by touch.

The circuit breaker is 15 Amps and is the neighbor of the one I replaced. They are original breakers from 1987.

I will double check the connections as the fridge/freezer is regularly running at 7 to 9+ amps depending on compressor speed. The freezer is keeping everything rock solid.


Sent from somewhere other than where I want to be!

[onestepcsy37]

I 'upgraded' my fan by adding a second fan. Richard Kollman advises that keeping the control module cool will prolong its life. So I mounted a computer fan the same size as the AB fan above the unit so that it blows on the module and compressor and pushes air into the AB fan. It runs off the extra connection on the module so no relay is needed. Has worked for 10+ years now with no problems. Fan cost less than $10.

Sent from my GT-P3113 using Cruisers Sailing Forum mobile app

[Doug Brown]

Hi -

I have always removed the "stock" AB fan and replaced it with one of the 6" diameter Hella cabin fans. I wire it into the AB unit where the AB fan went so it goes on and off as needed like the AB fan.

The Hella fan draws less amps and the 6" diameter fan blades move a ton more air over the entire AB compressor unit, keeping all the compenents much cooler.

Works like a charm!

[zboss]

Originally Posted by Doug Brown

Hi -

I have always removed the "stock" AB fan and replaced it with one of the 6" diameter Hella cabin fans. I wire it into the AB unit where the AB fan went so it goes on and off as needed like the AB fan.

The Hella fan draws less amps and the 6" diameter fan blades move a ton more air over the entire AB compressor unit, keeping all the compenents much cooler.

Works like a charm!

Where do the wires go?


Sent from somewhere other than where I want to be!

[Stu Jackson]

Originally Posted by zboss

Where do the wires go?

Didn't he say: "I wire it into the AB unit where the AB fan went..."???

I have replaced our fan with a Radio Shack 4 inch fan, $23 instead of $43 from A/B. Been working for 10 years.

FWIW, the fuses on our Cold Machine (fridge not freezer) are 10A. The builder put a 15A in the electrical panel, but the one on the unit is 10A. How do I know? The original unit, still on our boat, had a backup fuse in a small plastic bag right at the electronic module.

Check the connections. Always an issue with electrical stuff.

Good luck.

[zboss]

Stu don't be a jerk . I don't see anywhere to wire mine. Maybe he has a newer model.


Sent from somewhere other than where I want to be!

[Stu Jackson]

Originally Posted by zboss

Stu don't be a jerk . I don't see anywhere to wire mine. Maybe he has a newer model.

Not sure I understand. One fan, replace fan, wire to same place?

[SV THIRD DAY]

Originally Posted by onestepcsy37

I 'upgraded' my fan by adding a second fan. Richard Kollman advises that keeping the control module cool will prolong its life. So I mounted a computer fan the same size as the AB fan above the unit so that it blows on the module and compressor and pushes air into the AB fan.

That's great advice from Richard once again because a leading cause of death for the electronic control modules is heat death!

We situated our cooling fan to pull air through our condensing unit and it then blows directly on the heat dissipation fins on the Electronic Control unit. In fact, it’s recommended by both Danfoss and Cubigel to have cooling air directed on the cooling fins but most manufacturers don’t follow this advice and the price is dead electronic controllers due to heat.

[Cheechako]

Originally Posted by Stu Jackson

Not sure I understand. One fan, replace fan, wire to same place?

yeah... I don't get it either... there is a fan on there now right? On my ABCM there was a little terminal strip the fan connected to.

[Richard Kollmann]

Originally Posted by zboss

Well, I just pointed the laser at the wire sheath. The wire was noticeably warm by touch.

The circuit breaker is 15 Amps and is the neighbor of the one I replaced. They are original breakers from 1987.

I will double check the connections as the fridge/freezer is regularly running at 7 to 9+ amps depending on compressor speed. The freezer is keeping everything rock solid.


Sent from somewhere other than where I want to be!

Seven to 9+ amps would trouble me if this were true when plate was covered with frost. Does this amperage include a water pump?