Par max series freshwater pump 31395-4012 3v keeps cutting in when taps not in use.

[OlanBoomshanka]

Hi

 

Can anyone suggest how to stop thos from happening please. Its becoming more frequent and there are no signs of any leakages in the system . It first started happening when i accidently adjusted a red pressure knob on my clarifier . Thanks in advance

[Russ T]

So, once you have eliminated all external leaks, you are in the realms of internal leaks. A back leak through the pumps valve is usually a high possibility.

 

Option one is usually a visual check. It could also be you calorifier PRV functioning when water is heated. Back leak through the pump can be diagnosed if you have a shut off valve at the exit of the water tank, before the pump. Turn it off and see if the pump stops.

 

Other answers will follow.

 

Welcome

[Jen-in-Wellies]

Welcome to the forum.

 

Does the red knob look like this?

https://www.midlandchandlers.co.uk/products/surejust-pressure-relief-valve-1-2-3-bar-sj-prv3

If so, it is a pressure relief valve and the red knob on your cauliflower is leaking water, causing the pressure to drop and and the pump to kick in. It is not an adjustor. It is there to allow you to flow water through to flush away any limescale on the valve seat that is causing it to leak. You've probably left it on a slightly open position, rather than closed. Turn it a few more times and leave it on a mid position and see if this stops the drip. The thing the red knob is on is a pressure relief valve. There to bleed off excess water pressure that could endanger the cauliflower. 

[cuthound]

1 hour ago, Jen-in-Wellies said:

Welcome to the forum.

 

Does the red knob look like this?

https://www.midlandchandlers.co.uk/products/surejust-pressure-relief-valve-1-2-3-bar-sj-prv3

If so, it is a pressure relief valve and the red knob on your cauliflower is leaking water, causing the pressure to drop and and the pump to kick in. It is not an adjustor. It is there to allow you to flow water through to flush away any limescale on the valve seat that is causing it to leak. You've probably left it on a slightly open position, rather than closed. Turn it a few more times and leave it on a mid position and see if this stops the drip. The thing the red knob is on is a pressure relief valve. There to bleed off excess water pressure that could endanger the cauliflower. 

 

And depending on the boat builder, may drain into the bilge or be piped to a skin fitting. Either way there will be no obvious leak inside the boat.

 

Follow the pipework to see where it goes and look for leaks from there.

[Tony Brooks]

To add, the PRVs often click as you turn them and they get stiffer and easier to turn as you rotate it. Ensure it is in the "easy" position because that tells you that you are no longer trying to lift against the spring, so it should then be seated, if you can still see a drip from wherever its outlet is then it is a new valve, but do not get one that opens at a higher pressure than the one you have. That could burst the calorifier.

[OlanBoomshanka]

Thanks everyone for the response, its much appreciated There is no leak at the calorifier. The Red Knob is exactly the same so am i correct in thinking that its this Red Knob that needs to be turned / adjusted ?

[Jen-in-Wellies]

14 minutes ago, OlanBoomshanka said:

Thanks everyone for the response, its much appreciated There is no leak at the calorifier. The Red Knob is exactly the same so am i correct in thinking that its this Red Knob that needs to be turned / adjusted ?

How do you know there is no leak at the calorifier? Have you found out where the outlet goes? See @cuthound's post above. 

Have you turned the knob to it's "easy" position, as described by @Tony Brooks. This knob isn't to adjust anything. It is there to flush water through to clear any scale that is causing it to drip. 

[Russ T]

23 minutes ago, OlanBoomshanka said:

Thanks everyone for the response, its much appreciated There is no leak at the calorifier. The Red Knob is exactly the same so am i correct in thinking that its this Red Knob that needs to be turned / adjusted ?

If the red knob is part of a pressure release valve, then, yes turn it a few times.

 

Does this valve look like the one in the image (url) posted by Jen? There is a slim possibility that you are actualy talking about some kind of pressure reducing/temperature control valve and not a PRV.

 

Post a pic to be sure.

Edited February 4 by Russ T

[OlanBoomshanka]

Yes the red know is the same one as in the message that Jen posted. Apologies if i am not replying on the correct post because this is my first day on here and i am not that much into techy things and forums etc. There doesnt appear to be any leaks around the calorifier and there is not water collecting anywhere in the engine bay or the area where the pump is located and all the connections for my taps are bone dry plus there are no leaking taps etc. My heating is by the back boiler on my wood burner, which serves 4 radiators and i do not have any water heater as such other than the calorifier when the engine is running. I am pretty hard core and take cold showers even in winter. The pump noise kicks in about every 10 to 15 minutes and its been like this for about a week but it did very occasionally do it a few times per day. I have had the see through plastic filter off and made sure there is no debris inside it and i have checked that all the terminals are secure and connected etc

[Jen-in-Wellies]

There are four main causes of a pump running every ten to fifteen minutes. 

A dripping tap. Doesn't take much. 

A leaking joint. Have you found and inspected them all? 

The Pressure relief valve dripping. The one we have been concentrating on

The internal valve in the pump bleeding pressure back to the main cold tank. Rare, but it does happen. If there is an isolating valve between the tank and the pump, turn it off. See if this stops the pump running happening. This isn't a solurion, but a diagnostic test. 

[MrsM]

Another option: when we had the same issue we traced it back to a tiny pinhole perforation in the calorifier. Only discovered when we cut back the insulation to investigate it. There wasn't any noticeable water dripping underneath the calorifier but we had ruled out everything else.

[MtB]

1 hour ago, OlanBoomshanka said:

There doesnt appear to be any leaks around the calorifier

 

This is good news, although as MrsM points out, a small leak on a hot calorifier will soak into the foam insulation and evaporate/wick away rather than make the floor wet.

 

But it is more probable that one of the other four reasons Jen listed will be the cause. 

[OlanBoomshanka]

Thanks to everyone of you who has given me advise its very much appreciated. I havent found a solution just yet but i will investigate further tomorrow and hopefully solve the problem. 

[Iain_S]

Our pump started cutting in for about a second every half hour or so. Cause was water in calorifier cooling down, combined with an accumulator which had lost its pressure.

[OlanBoomshanka]

I dont think that its anything to do with cooling because its not that often i run my engine as i make do with cold water. I only run my engine on monthly checks but thanks all the same

[Tony Brooks]

4 hours ago, OlanBoomshanka said:

I dont think that its anything to do with cooling because its not that often i run my engine as i make do with cold water. I only run my engine on monthly checks but thanks all the same

 

but an accumulator with low or no air pressure, or no accumulator at all, would allow the slightest leak to make the pump run more often than it would with a properly pressurised accumulator. 

 

If it was doing it before you messed with the PRV then maybe there is a leak or a leaking valve in the pump. If not, then the PRV is a more likely culprit. The trouble is we have not been given the full story, like why did you feel the need to mess with the PRV, so we don't know all the symptoms.

[OlanBoomshanka]

Hi Tom

 

I didn't feel the need to mess with that red valve i was just wiping things down and accidentally rubbed ir and I heard some air escape. Its spring loaded . I have been playing about with it and i can hear it let water out of the side oof the boat and now the um is kicking in about every 2/3 mi utes so i am going to ask someone to have a look at it because its driving me nuts and i dont know what i am doing. I have lived on my boat for 7 years and i have never had this problem before.

Sorry not Tom, i meant Tony

[Tony Brooks]

7 minutes ago, OlanBoomshanka said:

Hi Tom

 

I didn't feel the need to mess with that red valve i was just wiping things down and accidentally rubbed ir and I heard some air escape. Its spring loaded . I have been playing about with it and i can hear it let water out of the side oof the boat and now the um is kicking in about every 2/3 mi utes so i am going to ask someone to have a look at it because its driving me nuts and i dont know what i am doing. I have lived on my boat for 7 years and i have never had this problem before.

Sorry not Tom, i meant Tony

 

Before doing anything costing money, leave the pump turned on and give the knob several twists, so water flow flushes the valve seat, but I suspect the initial brushing of the knob may have caused a very rusty spring to snap.

 

If it needs changing, two threads to undo and then do up on the new valve. Plumbers merchants sell such valves, but get one set to the same pressure as the existing one. Have the pump off and a tap open when you do the job, and in many cases no or very little water will be lost.

 

It is just a "nut and bolt" job plus putting a bit of PTFE sealing tape or other sealer on the male threads that you screw into the new valve.

[OlanBoomshanka]

Thanks for that Tony, i have noticed that there is a bit of a leak coming from somewhere but its nothing substantial . It must have been leaking the last 24 hours bevcause it was bone dry before that. I will post a picture of the area and the red knob i have been refering too in a few minutes. I was wondering if i ran the engine , would that build up the pressure and make any diference at all ?

[Jen-in-Wellies]

6 minutes ago, OlanBoomshanka said:

I was wondering if i ran the engine , would that build up the pressure and make any diference at all

None at all. 

[OlanBoomshanka]

Ok...thanks Jen

[Russ T]

This is a link to Tonys excellent website. It won't help you fix your system, but may give you a better understanding of the individual components,how they fit into the system and what they do

 

http://www.tb-training.co.uk/17Bdomwat.html

Edited February 5 by Russ T

[OlanBoomshanka]

Great, i will have a look at that once i manage to resolve thos issue because my brain can only cope with so much frustration at a time. The pump has been kicking in all night so i havent slept well

Thats the red knob that started my problems

[Russ T]

Just now, OlanBoomshanka said:

Great, i will have a look at that once i manage to resolve thos issue because my brain can only cope with so much frustration at a time. The pump has been kicking in all night so i havent slept well

If your system has a switch (often in the galley), turn it off overnight, or pull the circuit breaker. Turn it back on in the morning until you have the problem fixed.

[Tony Brooks]

To add to my last reply. @OlanBoomshanka if you do decide to change the valve yourself look very closely at the parts that screw into the valve/the valve screws onto. They should have a hexagon on them. Make sure you prevent that (or the valve) twisting when you undo the thread, so two hexagons involved. If you have non-pushfit connections to the valve you may have to take of another pipe or hose connection to allow the said threads to turn.