Pressurized Freshwater System

May 15, 2022
10
Hunter 456 Portland, CT
I bought a 2002 456 CC last year and am spending the next few seasons getting to know her before doing any prolonged cruising around New England. I noticed a few months ago that my freshwater started to smell and finally got around to flushing the system. I have the boat on a mooring, so I procrastinated. Well, when I finally got around to it the lines had some an obstruction...probably some sort of growth in the tank that got lodged in one of the lines. I ended up back-blowing out the lines with compressed air, but in the process was amazed at how much water kept coming out of the lines when they were under "back pressure." I don't believe there's an accumulator tank in my system (in normal use the pump always runs when I turn on the water), but wondering if the hot water heater was acting as an accumulator. Any thoughts or experience out there? Semper Sailor
 
May 15, 2022
10
Hunter 456 Portland, CT
I blew air from the pump connection back to the tanks, and then blew air forward into the distribution system...which is when water just kept flowing and flowing. Seemed like much more than what the just the lines would hold.
 
Jan 7, 2011
5,278
Oday 322 East Chicago, IN
You might have an accumulator tank…maybe not working well. Mine delays the water pump for a short period if I open the faucet all the way…if the pump is off, I get a fair amount of water from the faucet before it finally drips out.

Also, if you were blowing into the “distribution system”, you were pressurizing the water heater…and if you opened the hot water tap on the faucet, you would be emptying your 6-gallon water heater before running dry. This assumes you didn’t by-pass the WH. Depending on your plumbing, you may not even need to open the hot water tap…


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Good luck, I hope you get it figured out.

Greg
 
Jun 1, 2009
1,813
Hunter 49 toronto
You might have an accumulator tank…maybe not working well. Mine delays the water pump for a short period if I open the faucet all the way…if the pump is off, I get a fair amount of water from the faucet before it finally drips out.

Also, if you were blowing into the “distribution system”, you were pressurizing the water heater…and if you opened the hot water tap on the faucet, you would be emptying your 6-gallon water heater before running dry. This assumes you didn’t by-pass the WH. Depending on your plumbing, you may not even need to open the hot water tap…


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Good luck, I hope you get it figured out.

Greg
Be careful with compressed air in this situation. You could rupture a tank.