Fresh water pump upgrade - mistake?

superboots

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Have I made a mistake in buying a replacement fresh water pump of a different specification?

Existing pump is Shurflo AquaKing standard model 2095 423 243 12 v 30 psi 21. bar 10 amp 10.6 lt/min

Replacement AquaKing ll model 4149 153 B86 12 v 40 psi 2.8 bar 15 lt/min .

connections are the same . Old one has started to leak and may fail as its quite old although the motor seems fine

asked the dealers but no satisfactory replies received
 

madabouttheboat

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The only possible problem I can see is that the higher pressure MIGHT set off any pressure relief valves in your system if they were spec'd for lower pressure. The higher pressure might also show up any weaknesses in your system that were ok with the lower pressure. Other than that, I doubt it will be a problem
 

Stemar

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It isn't a huge difference in pressure. I reckon anything that failed because of it is probably on its way out anyway, so failing when you're already messing about with the system rather than on a cruise, days away from spares, is a bonus
 

VicS

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Check the max amps / recommended fuse value. You may need to increase the fuse value.

Higher pressure may need the accumulator pressure to be increased in addition to points made by madabouttheboat, That is if you have an accumulator.
 
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superheat6k

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I did this on my Corvette. Increase in pressure was similar. All OK for ages then I noticed a leak near the calorifier tank. I then found the tank (a miniature version of a domestic tank) had bulged considerably, and then had split on a brazed seam. After several repair attempts I ended up with a new calorifier.

However, a simple pressure switch set to a lower pressure would likely resolve the high pressure problems.
 

VicS

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I did this on my Corvette. Increase in pressure was similar. All OK for ages then I noticed a leak near the calorifier tank. I then found the tank (a miniature version of a domestic tank) had bulged considerably, and then had split on a brazed seam. After several repair attempts I ended up with a new calorifier.

However, a simple pressure switch set to a lower pressure would likely resolve the high pressure problems.

ITYWF that the pump pressure switch is adjustable and can be set to a lower pressure. However the bypass control valve will then have to adjusted to maintain correct operation , taking care not to reduced the bypass opening pressure to below that of the pressure switch or the pump will run continuously.

There is some information on this in the instruction manual.

.
 

superboots

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Thanks for all your replies. Maybe I should switch pumps now before the old one breaks and see if there are any unwished for consequences from the new pump
 

Tintin

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It'll be fine. Try it now. Most of us have probably got boxes of bits we meant to fit, with that boat now sold :)
 
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