Low fresh water pressure - Hot water tank not filling

[joefish24]

Hi all, I have a 2019 C24 that was in service last year, winterized for NY storage in my driveway, now I'm getting it ready for splash this week. On my freshwater system, I'm getting a burst of good pressure from all faucets, but after 3-5 seconds or so it slows down dramatically with very poor pressure. I noticed during all this that my hot water tank is not filling with water, it's still completely empty so I'm thinking it's some kind of prime/airlock issue. Maybe the positioning in my driveway is impeding a good prime? The pump is working fine from what I can tell and just to make sure i disassembled the strainer under the galley sink to make sure no blockage, all clean. I'm out of ideas here. Should be very simple to get this going again but I'm stuck here. Any assistance would be greatly appreciated!

 

[Brian B]

Was the hot water tank bypassed when it was winterized and not reconnected? Loss of pressure could be air getting into the pump filter screen.

 

[joefish24]

Thanks for your reply. Yes the hot water tank was bypassed but has since been reconnected. I did take a look at the filter screen, looks good and I can't see that air is getting in there, no leak at the pump location either that I can tell.

 

[NorthernFocus]

Is the pump running continuously or does it cycle off?

 

[joefish24]

The Pump runs for a few seconds and shuts off as normal so I don't feel it's a leak.

 

[Brian B]

How about disconnecting the “In” supply line of the water heater, turn the pump on and see if you have water coming through that line. If no water then backtrack the line.
Also could the lines have been reversed when they were re-connected?

 

[joefish24]

Ok, i checked and the lines off the boiler are not reversed. red connected to red (top position), blue to blue. Will check for water coming out of the line feeding the tank and advise.

 

[Kevin Lamont]

Hi all, I have a 2019 C24 that was in service last year, winterized for NY storage in my driveway, now I'm getting it ready for splash this week. On my freshwater system, I'm getting a burst of good pressure from all faucets, but after 3-5 seconds or so it slows down dramatically with very poor pressure. I noticed during all this that my hot water tank is not filling with water, it's still completely empty so I'm thinking it's some kind of prime/airlock issue. Maybe the positioning in my driveway is impeding a good prime? The pump is working fine from what I can tell and just to make sure i disassembled the strainer under the galley sink to make sure no blockage, all clean. I'm out of ideas here. Should be very simple to get this going again but I'm stuck here. Any assistance would be greatly appreciated!

Hello,

When the system was emptied for winter it takes some time for the system to prime back up. I had this just yesterday on a boat. Open facets to cold only till you get some water flowing, wont be strong yet. Once they have water flowing shut them off and let the pump run, it has to fill the whole hot water tank (4 gallons) before it is primed and the pump shuts off, pump is rated for 2.9gal per min FYI. Just keep in mind it is not only filling the hot water tank but all the lines too. Opening them to hot once and a while when priming wont hurt but does take some time. If you are still having issues please feel free to email me direct if you have questions.

Thank you,
Kevin Lamont

 

[joefish24]

Thanks all, after some time diagnosing today I think I determined it's the pump itself. I removed all piping and just witnessed the water moving slowly out the pump exit, same as what the faucets are getting. Pretty unbelievable given it's so new but it should be under warranty.

 

[NorthernFocus]

Thanks all, after some time diagnosing today I think I determined it's the pump itself. I removed all piping and just witnessed the water moving slowly out the pump exit, same as what the faucets are getting. Pretty unbelievable given it's so new but it should be under warranty.

Do you mean you removed the discharge hose but still pulling water from the tank? If so you might want to check the inlet line from the tank before replacing the pump. Not sure if there is a strainer at tank or pump inlet but if the pump runs but has low flow that typically indicates a restriction on the inlet side.

 

[FWTMD]

Throwing in two cents here. Seems to me I've read here in Tugnuts there is a frequent issue with new boats (both RT and C's) where there is a material amount of construction debris in the water lines and tanks, and the bilges. Which needs to be flushed out and cleared. All screens in the paths cleared. Weep holes cleared. Including the screens at the faucet heads. From end to end. I'd think about clearing it in some manner it doesn't wind up in the bilge causing trouble down the trail to the bilge pumps, and then the pumps themselves.

This boat is new.

The earlier discussion had me adding this to my purchase shakedown maintenance list.

Just a thought.

 

[joefish24]

Thanks all, after some time diagnosing today I think I determined it's the pump itself. I removed all piping and just witnessed the water moving slowly out the pump exit, same as what the faucets are getting. Pretty unbelievable given it's so new but it should be under warranty.

Do you mean you removed the discharge hose but still pulling water from the tank? If so you might want to check the inlet line from the tank before replacing the pump. Not sure if there is a strainer at tank or pump inlet but if the pump runs but has low flow that typically indicates a restriction on the inlet side.

Thanks for your reply, yes you are right in that I removed the discharge hose and it's still pulling water from the tank but pretty slowly. I removed the inlet line too, other than the main screen (which is clean) i don't see anything else that could restrict water. Perhaps something in the tank itself is blocking things? I wonder if I shot some compressed air down to the holding tank, maybe it would dislodge it. This is a pretty simple system, I'm not sure where else the problem could be!

 

[joefish24]

Throwing in two cents here. Seems to me I've read here in Tugnuts there is a frequent issue with new boats (both RT and C's) where there is a material amount of construction debris in the water lines and tanks, and the bilges. Which needs to be flushed out and cleared. All screens in the paths cleared. Weep holes cleared. Including the screens at the faucet heads. From end to end. I'd think about clearing it in some manner it doesn't wind up in the bilge causing trouble down the trail to the bilge pumps, and then the pumps themselves.

This boat is new.

The earlier discussion had me adding this to my purchase shakedown maintenance list.

Just a thought.

It's a valid point but i don't see where it could collect since I have eliminated the possibility of all the pipes going to the fixtures being a problem (i removed the discharge completely and still have poor flow). So if debris is clogging things up, it would be between the freshwater tank and the pump itself, which is not really serviceable. i was thinking to maybe shoot compressed air down to the tank as a next step.

 

[FWTMD]

I don't yet own one, so I'm the wrong guy to get specific.

But it sounds like either something has already fouled the pump and plugged it, or its up the line to or in the tank. If you have already pulled the intake hose and get no flow, there's your answer.

Do a search here. There was some discussion on the issue, which is why I flagged it for my own checklists. Seems to me you can open the tank and reach in to remove debris from it. If none, then its been narrowed to the line from there to the pump.

Wish I could help more.

 

[Salty7]

Is your water tank definitely full so there really is water for the pump to feed into the rest of the system?

 

[bob daily]

Ok Bob's two and 1/2 cents worth!
Sounds like you have already narrowed it down to the pump or supply line. Remove pump and test, you will need some tubing and a power source (car battery) and a bucket of water.
If pump is good than the next step would be to clear the line, I would use my air compressor and blow front the tank to the suction line, this way whatever is hampering the flow will not be pushed back to the water tank and cause problems in the future. Your right it's a pretty simple system but they can cause the most problems. Good luck! Bob

 

[NorthernFocus]

... i was thinking to maybe shoot compressed air down to the tank as a next step.

It might be both simpler and certainly safer to disconnect the inlet hose from the pump and run a fish tape(or similar) towards the tank. Something with a worm on the end that can pull out any obstruction would be ideal.

 

[joefish24]

I was able to clear the line somewhat by blowing compressed air down to the tank but after some time it clogs back up. I see no way to get access to the tank to clean it unfortunately. I noticed when the tank is 100% full I get perfect suction and flow but when it drops below 75% full it again reduces down to an unacceptable level. Could there be a crack in the top of the tank that is blocked when full and exposed when the water level drops?

Regarding the hot water tank that was not filling, I did finally figure that out. My dealer winterized the boat but when bypassing the hot water tank to flush the system with antifreeze, he accidentally put the one-way connector on backwards. That drove me crazy till I spotted the arrow pointing the wrong way..

 

[joefish24]

Ok Bob's two and 1/2 cents worth!
Sounds like you have already narrowed it down to the pump or supply line. Remove pump and test, you will need some tubing and a power source (car battery) and a bucket of water.
If pump is good than the next step would be to clear the line, I would use my air compressor and blow front the tank to the suction line, this way whatever is hampering the flow will not be pushed back to the water tank and cause problems in the future. Your right it's a pretty simple system but they can cause the most problems. Good luck! Bob

Thanks Bob, how would I gain access to the tank side? Seems all inaccessible from what I can see.

 

[bob daily]

I would try to pressure the tank from the fill connection, you will have to block off the vent, you will only need a few psi of pressure to push the water out. Tape (duck tape) over the vent to water tank and rig a fitting for your external water fill fitting. I will post a picture of a fitting I use for winterizing the pool that will give you a ideal of what I'm talking about. It will be in my photo album shortly
Hope this helps

Edit: you said you had good pressure till the tank dropped below about 75% that would indicate that you might have a clogged vent line which would cause the problem your describing! To check for a plugged vent just leave the fill cap off and run the pump and see if you still have good pressure.
Bob