Whole house (boat) water filter

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Wmiii

Senior Member
Joined
Oct 29, 2011
Messages
119
Location
USA
Vessel Name
OPTIMYSTIQUE
Vessel Make
Mariner 40
My boat has a GE water filter set up between the tanks and the waterpump. When we first got the boat, the water pressure was fine. Then I thought I should change the filter because I didn't have any idea how old it was. I found some filters at Home Depot and replaced the old filter. Unfortunately, my water pressure dropped with the pump running fast. I thought I was getting air in the system so redid all connections and still the problem. I thought I must have a crack somewhere in the old housing, so for $20, I bought another. Still not quite up to full flow.
I've noticed that my pump is a 4 gpm unit and the filters are 1-.5 gpm.
Could that be my problem?
It still works great bypassing the filter.
Ideas?

Thanks,

Wm Mayberry
OPTIMYSTIQUE
Mariner 40

Marathon, FL
 
Greetings,
Mr. Wm. Yup, I think your filters will not pass enough water proven by your bypass of same.
 
I figure on 2 GPM for each "thing" that is on at a time.

Based on that, (and the fact that when you bypass your filter everything is fine), your 1.5gmp filters are restricting your flow
 
It sounds like the filter is restricting the flow. We installed whole house Culligan filtration system. Replacement filters are standard replacement filters. Have no idea what the flow rate limit might be, but being set up for household use I'm sure it is more that we can push through it on the boat.
 
I have my filter mounted after the pump, rather than before the pump like yours. Perhaps that will make a difference. I haven't noticed any significant change in pressure since adding the filter. It may be easier for the pump to push the water through rather than suck it through the filter.
 
Now I need to see if I can find higher capacity filters.












Thanks,
Wm
 
A home water filter is designed for the water to be forced through it. The pump should be upstream.
 
Start by moving the filter to after the pump. If the pump is designed to deliver 4 gpm, then adding a filter rated for 1.5 gpm will definitely move the pump's output down the curve. Finding a filter rated for 4 gpm to fit your canister should not be hard.

What are you trying to remove with the filter?
 
I have two filters up line from my pump and have no issues. Little less water flow yes, a little. But this last summer, somewhere in Canada, I picked up some sand. The filters stopped the sand from damaging the pump.
 
Centrifugal pumps are affected most by suction side restrictions. Positive displacement pumps not so much. And at some point, a "filter" becomes a strainer. Keeping sand out of your impeller or tank doesn't require a particularly fine filter.
 
Why not replace the "whole house" filter with a faucet filter on the galley faucet? That's the only place you'll ever run water for drinking, cooking, coffee etc. Any water issues anywhere else is a clue that it's time to recommission the system.
 
I have two filters up line from my pump and have no issues. Little less water flow yes, a little. But this last summer, somewhere in Canada, I picked up some sand. The filters stopped the sand from damaging the pump.

If you picked up sand, your intake was too close to the bottom. Is there something you should be telling us about what happened on your trip?
 
A home water filter is designed for the water to be forced through it. The pump should be upstream.

Absolutely right! Many of our pumps are heavy on pressure and light on suction. Move the filter to the pressure side of the pump.

Why not replace the "whole house" filter with a faucet filter on the galley faucet? That's the only place you'll ever run water for drinking, cooking, coffee etc. Any water issues anywhere else is a clue that it's time to recommission the system.

I removed my "whole boat" filter and reinstalled it under the galley sink for that very reason. No sense in finely filtering the shower water!
 
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If you picked up sand, your intake was too close to the bottom. Is there something you should be telling us about what happened on your trip?

I will never tell!!:eek:

We think it came from one of the marinas in Canada......
 
I actually run our water through a RV filter when I fill my tanks as well as having a Pur filter on our Galley sink. I really don't need the 'House' filter and I think I will just keep by passing it and possibly rig it for my fill filter when I stop using the RV ones.
I had an Island Packet sailboat for many years that had aluminum tanks and I wanted to keep as much clorine out as possible, so just got in the water filtering habit.


Wm
 
I just removed the whole boat water filter that was on the discharge side of the pump. The ShurFlo Revolution type pumps sense any restriction and I had pump cycling. I've decided to filter the water going into my tanks with an in line hose type filter. Now I have full pressure and gpm flow from the pump with clean shut off on the pumps pressure switch.
 
I just removed the whole boat water filter that was on the discharge side of the pump. The ShurFlo Revolution type pumps sense any restriction and I had pump cycling. I've decided to filter the water going into my tanks with an in line hose type filter. Now I have full pressure and gpm flow from the pump with clean shut off on the pumps pressure switch.

:thumb::thumb::thumb:

Best plan is to filter the water before you put it into your boat.

Then, if you want, put a small filter on the galley sink.
 
I filter the water before it goes into tanks. Also have a filter in- line on the boat. Moved the pump to be before the filter. It is a lot quieter, not having to suck thru filter. Use tank water for water maker flushing, so filters are carbon, to remove chlorine.
 
I use 4.5x20 filter housings. They stand a very high rate of flow and because they're large filters, last a very long time. Best places to by housings and filters is Ebay or Amazon. My big filters are much cheaper than home stores and water companies.
 
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