Water stutter?

[Johnatkatys]

Refilled the water tank after winter. Got the water pump working again after resetting the o-ring in the filter cover (again).
But a strange thing happens: When I run hot water the flow is smooth as expected, but when I switch to cold water the flow stutters like a lawn sprinkler. This makes no sense to me. I made a short video.

Any ideas?

 

[Rode Trip]

A kink in the cold water line. Does the head do it also? That will tell you where in the line it's at.

 

[Johnatkatys]

A kink in the cold water line. Does the head do it also? That will tell you where in the line it's at.

Good idea, but it's not that. I looked and looked, but the pex is pretty tough stuff and there are no kinks.
But, I tried running cold water in Both the head and the galley and the frequency changed!!! This is being caused by the pump motor going on and off rapidly. And then it occured to me that in many systems there is an air bladder and reservoir to prevent exactly this kind of pump cycling! But something has changed in the Ranger Tug since last season. I don't think it used to do this. Maybe the setpoints in the motor?

 

[venajeff]

Sounds like your on to something. Maybe your hot water tank is acting like a reservoir and stopping it from happening. Perhaps the pressure shut off switch on the pump is faulty. Does it seam like your pressure is lower than it used to be? You could try opening all your cold water valves at the same time, if it works fine then I think that points to the pump.

 

[fishheadbarandgrill]

Pretty sure the pump is a little air bound. Let it sit over night and see if it settles down. You also might pull off the intake hose and let some of the water drain out of the pump, re-attach and see if the pump gets a good draw and clears out all the air. This has happened to me after I run the tank real low and then refill.

 

[Johnatkatys]

Refilled the water tank after winter. Got the water pump working again after resetting the o-ring in the filter cover (again).
But a strange thing happens: When I run hot water the flow is smooth as expected, but when I switch to cold water the flow stutters like a lawn sprinkler. This makes no sense to me. I made a short video.

Any ideas?

A lot of people saying air. I fooled around all day yesterday and indeed, reconnecting and wiggling joints made a difference although it did not eliminate the problem. But it convinced me to a) change out some PEX tubing and connectors and b) add an accumulator. The boat is now 8 and the PEX feels stiff and the connectors feel a bit loose. I’ll let you know how it goes in a week or two. J.

 

[Hamster]

Air in the lines is almost always what I experience after I drain the tanks and refill. I solve the issue by running the water while simultaneously opening the air/drain valve of the hot water tank. Takes care of the problem.

 

[Johnatkatys]

Thanks.

 

[New Adventure]

I was having similar issues turns out bait sink wasn’t shutting off completely not pouring but enough to kick pump on and stuttering water. replacing cartridges tomorrow

 

[Johnatkatys]

Here's a solution that worked beautifully!
I inserted a SeaFlo Accumulator (0.75l). Now the flow is smooth and the pump only turns on every few (2-3) seconds.

 

[JK13]

Yes the accumulator is what solved this for us too!
The hot water did not stutter as much because squishy air in the top of the hot water tank acts like the accumulator absorbing the impact shock waves from the pump.


🙂
Joe