Refrigeration Water Pump

[kiltym]

Hi,

So, I have a water cooled fridge, cruise full time in the Caribbean, and I am looking to replace my water pump. I have found these 3 options out there, some are used by the fridge re-sellers, some I found by talking to people.

If anyone has any votes as to what to use, that would be great. They all seem to put out more water flow then needed by a single compressor, and I have heard some people have "turned down" the pump by lowering the voltage to it. If anyone has experience doing that, please share it!

Basically, as we all are, I am looking for a long running, low maintenance, low energy water pump.

Flojet 4105-512 (this is what I use now. Works ok, but clogs easily in the tropics, draws about .7amps in my installation, but after 3 years of use, is in need of replacing. Frigoboat states this is the best pump available.)

Shurflu 8050-261-05 (it states the water flow is adjustable, but installers have told me its not, its set at .5gpm flow. Don't know much about this pump but one installer is recommending it.)

March 893-09 (50,000 hour run time, but does not self prime, which for me is OK as the pump and inlet will all be below the waterline anyway. States it draws 1amp, but curious as to what people have seen in real use.)

If anyone has other pumps, or other solutions, or thoughts on these I listed, please contribute to the thread as I know there are other water-cooled fridge people who want a better pump!

Thanks!
Mark

[2ndstar]

I have the March pump and have mixed feelings about it. It doesn't draw much current, less than an amp, is very durable, 4 plus years so far, and is very quiet. The downside is it won't self prime even mounted below the waterline, and doesn't move a lot of water, just enough to cool the compressor. Usually it will lose prime when sailing as a little air will get in the line.

Regards, Carl

[speciald@ocens.]

Get a pump with a magnetic impeller so it won't burn up when inlet or strainer is clogged.

[CarinaPDX]

One way to get a FloJet or Shurflo to work in this environment is to install the 24v version of the pump and run it directly off 12v. This will result in a lower flow more appropriate to the need. I have done this to good effect in the past. By all means protect the pump and controls with a carefully chosen fuse or circuit breaker on the pump. Also, check that your compressor has a temperature cutout rigged so that if your pump is unable to cool the system it will shut down instead of overheating. I suppose that overheating could damage the pump but I think the bigger problem is that the R134a breaks down and stops making the phase change.

One expensive refrigerator used a zinc upstream of the heat exchanger, which would block with bits of zinc and drive the back pressure up; the pump then drew too much power and burned out the (expensive and not protected) power converter which regulated 12v down to 5v. Dumb. Which is how I ended up using a 24v pump on 12v with a fuse.

Ultimately I gave up on using a water pump - just too many problems and too much power consumption. I am now using a keel cooler which has been a big winner in every way: no maintenance, sound, or power consumption.