Raw Water Pump Operation

[Dean Fagan]

Is it necessary to run the raw water pump when ever the refrigeration system is operating? When leaving the boat for extended periods of time during the week I have been leaving the pump on and wondered if that was the correct thing to do.

 

[Steve Dion]

Last weeks reply to your question

Here is Bill reply to this question last week:"This is one of the most misunderstood areas of marine refrigeration. The water pump should only be run when the ambient temperature at the compressor is 100 degrees or more. Below this temperature, you do not get rid of any more heat with the water than you would with the air. BUT!, because you are drawing an extra amp for the pump, it is actually less efficient to run it at lower tempseratures. The pump also should not be run at dockside. There is the chance of getting a baggie or other floating debris against the intake. This would cause the pump to run dry requiring a repair kit. When at dockside, plugged into shore power with the charger running, it is usually not a concern to save a couple of amps. The pump can be reprimed if needed by closing the thru-hull, removing the pump outlet hoseand filling the wet end with water, purging any air in the process."Bill, send cash no checks please.Steve Dions/v Heather Marie

 

[Rich]

Steve is right, just be sure...

Dean, Steve is right about not needing to run the raw water cooling pump for your refrigeration. I've never had to use mine and I leave my fridge on all of the time. Just make sure that your compressor has a fan to keep it from overheating. Most newer systems are designed with optional water cooling as opposed to water cooling that must run all of the time. I have seen some older systems that do not allow for the water to be turned off when the fridge is turned on. Since you're asking the question though I'll make the assumption that this is optional. I would not leave the boat with raw water being pumped into it unattended. Too many bad things can happen.