Water System Query

[Steph H]

I'm trying to understand the water system on my boat. I know where the outlet pipe comes from the tank, and I can tell I've got a small calorifier for the kitchen sink and the main water pump. What I'm not sure about is the other bits.

 

I've added a couple of photos one which I've labelled with the bits I recognise.

 

Any help would be appreciated, thank you ?

 

Ignore my label of calorifier I've now been told it's an accumulator. ?‍♀️

 

 

Edited August 25, 2020 by Steph H

[Keeping Up]

That's not a calorifier, it's an accumulator which is a pressure reservoir to stop the pump from cycling rapidly. The square grey thing is a separate pressure-switch (a Square D) which is good because the ones in the pumps are unreliable.

[Steph H]

8 minutes ago, Keeping Up said:

That's not a calorifier, it's an accumulator which is a pressure reservoir to stop the pump from cycling rapidly. The square grey thing is a separate pressure-switch (a Square D) which is good because the ones in the pumps are unreliable.

Oh ok! My mistake, thank you for putting me right.

 

?

[AndrewIC]

Your “calorifier” looks more like a pressure accumulator. The beige square box is a pressure switch. The arrangement with the red knob looks like a pressure relief valve, presumably the intention is to divert over-pressure back into the tank - never seen that arrangement before though. I don’t understand the white valve at the bottom of the picture though.

[BEngo]

The thing you have labelled calorifier is in fact the accumulator.   It appears to be rusting and is probably close to failure.  It should be renewed before it starts leaking and the pump empties your water tank into the bilges 

 

The thing with a red ring  connected  to the black  pipework appears to be a pressure relief valve.  This will stop the downstream pipes from being overloaded if the pressure switch fails.

 

I am not sure why there is a white valve (with round knob) next to it.  It appears to bypass the pump  and could be used with the pump off to depressurize the water system, though opening a tap with the pump off would do that too.

 

The clear plastic thing next to thr pump is a strainer or coarse filter.  It needs an occasional dismantle and clean.

N

Edited August 25, 2020 by BEngo

[Steph H]

5 minutes ago, BEngo said:

The thing you have labelled calorifier is in fact the accumulator.   It appears to be rusting and is probably close to failure.  It should be renewed before it starts leaking and the pump empties your water tank into the bilges 

 

The thing with a red ring  connected  to the black  pipework appears to be a pressure relief valve.  This will stop the downstream pipes from being overloaded if the pressure switch fails.

 

I am not sure why there is a white valve (with round knob) next to it.  It appears to bypass the pump  and could be used with the pump off to depressurize the water system, though opening a tap with the pump off would do that too.

The clear plastic thing next to thr pump is a strainer or coarse filter.  Ot needs an occasional dismantle and clean.

 

Ok thank you, will look into getting the accumulator replaced.

 

 

 

This probably will be a dumb comment ?

 

But the whole system shown takes up a large amount of floor space under some seating, is there any way of compressing all of this? How close to the water tank does it all need to be? Could it be moved further along the pipework to a more convenient (for me) space?

Edited August 25, 2020 by Steph H

[Machpoint005]

3 minutes ago, Steph H said:

But the whole system shown takes up a large amount of floor space under some seating, is there any way of compressing all of this?

 

It all has to be somewhere. The way it is, at least you can get at each component when it fails (NB: I deliberately did not say "if it fails").

[dmr]

28 minutes ago, Steph H said:

Ok thank you, will look into getting the accumulator replaced.

 

 

 

This probably will be a dumb comment ?

 

But the whole system shown takes up a large amount of floor space under some seating, is there any way of compressing all of this? How close to the water tank does it all need to be? Could it be moved further along the pipework to a more convenient (for me) space?

Yes, the stopcock should be right next to the tank but the rest can move to a more convenient place. Keep good access to the pump, it will fail and need replacing at some stage. The little white valve can most likely go, I don't know what it does. The thing that we assume is a pressure relief valve can maybe go somewhere else to discharge overboard. The pump should ideally be mounted upright (vertically) on the wall somewhere. Some people say the pump should be connected with short lengths of flexible/rubber hose rather than plastic pipes, its a good idea but a nicety rather than essential, might make the plumbing a tiny bit easier. It could all be a bit neater and take up a bit less space.

 

...............Dave

[blackrose]

Connecting the pump with flexible pipe isn't essential until the pump vibrates one of the rigid connections loose or cracks it. Essential or not it's just best practice to do it properly with flexible connections and it should help to reduce pump noise a bit too.

 

If the pump is mounted vertically on a bulkhead then make sure it's the right way around with the pump head below the motor.

[Steph H]

8 hours ago, dmr said:

Yes, the stopcock should be right next to the tank but the rest can move to a more convenient place. Keep good access to the pump, it will fail and need replacing at some stage. The little white valve can most likely go, I don't know what it does. The thing that we assume is a pressure relief valve can maybe go somewhere else to discharge overboard. The pump should ideally be mounted upright (vertically) on the wall somewhere. Some people say the pump should be connected with short lengths of flexible/rubber hose rather than plastic pipes, its a good idea but a nicety rather than essential, might make the plumbing a tiny bit easier. It could all be a bit neater and take up a bit less space.

 

...............Dave

Thank you. I think I've got just the spot that has easy access but is out of the way.

7 hours ago, blackrose said:

Connecting the pump with flexible pipe isn't essential until the pump vibrates one of the rigid connections loose or cracks it. Essential or not it's just best practice to do it properly with flexible connections and it should help to reduce pump noise a bit too.

 

If the pump is mounted vertically on a bulkhead then make sure it's the right way around with the pump head below the motor.

It does vibrate and I can tell it's because it's not screwed down properly, definitely something I will rectify.

 

Thank you

[Tony Brooks]

Re the understanding - look in the water section of the maintenance notes here -

www.tb-training.co.uk

[Tony Brooks]

The valve with the red knob - the PRV - is in exactly he same position as where I put mine because it vents water back into the tank when/if it opens. However it is useless there if there is a non-return valve on the cold inlet to the calorifier (hot water cylinder) so that needs investigation. If the hot water comes from an instant gas water heater then the PRV is not needed but it won't do any harm until it leaks.

 

I can only think the white valve is to allow the tank to be drained via and external pump connected to a drain point somewhere, possibly near any calorifier.

 

I have a suspicion that this is an ex hire boat laid out for minimal breakdowns and easy maintenance. In my view that is good. It would explain why the PRV is where it is, No hirers phoning up saying hot water keeps leaking from the boat.

 

If this is a holiday boat then you might thin about mounting the whole lot on a board with easy to undo pipe connections. That way you can drain down and take all those expensive bits home for the winter to prevent frost damage.

 

Are you aware that the water pump should NOT be screwed down tight. The screws shoudl just be tight enough to locate it in position. If you tighten it down hard it will transmit vibrations to the board under it and that may well resonate and make the vibrations worse.

Edited August 26, 2020 by Tony Brooks

[Steph H]

9 minutes ago, Tony Brooks said:

The valve with the red knob - the PRV - is in exactly he same position as where I put mine because it vents water back into the tank when/if it opens. However it is useless there if there is a non-return valve on the cold inlet to the calorifier (hot water cylinder) so that needs investigation. If the hot water comes from an instant gas water heater then the PRV is not needed but it won't do any harm until it leaks.

 

I can only think the white valve is to allow the tank to be drained via and external pump connected to a drain point somewhere, possibly near any calorifier.

 

I have a suspicion that this is an ex hire boat laid out for minimal breakdowns and easy maintenance. In my view that is good. It would explain why the PRV is where it is, No hirers phoning up saying hot water keeps leaking from the boat.

 

If this is a holiday boat then you might thin about mounting the whole lot on a board with easy to undo pipe connections. That way you can drain down and take all those expensive bits home for the winter to prevent frost damage.

 

Are you aware that the water pump should NOT be screwed down tight. The screws shoudl just be tight enough to locate it in position. If you tighten it down hard it will transmit vibrations to the board under it and that may well resonate and make the vibrations worse.

Yes it is an ex hire boat but I'm renovating it to become a liveaboard, hence the desire to make the floor space the whole set uses minimal. I'll be living aboard through winter so shouldn't need winterising. The hot water tank/calorifier is at the other end of the boat.

 

Will keep that in mind about how tight the screws should be on the pump, thank you.

[Tony Brooks]

30 minutes ago, Steph H said:

Yes it is an ex hire boat but I'm renovating it to become a liveaboard, hence the desire to make the floor space the whole set uses minimal. I'll be living aboard through winter so shouldn't need winterising. The hot water tank/calorifier is at the other end of the boat.

 

Will keep that in mind about how tight the screws should be on the pump, thank you.

In that case you don't need the white valve and pipework when you reposition it all.

 

The accumulator can go anywhere on the COLD system so look for odd lost space under double beds etc. It rarely needs attention. The PRV can be relocated to the hot side of the calorifier (where most people expect to find it) and the outlet piped into the engine room bilge or overboard.  Although the accumulator will act as an expansion vessel as well providing there is no non-return valve on the cold inlet to the calorifier it may dribble a bit so hence the outlet going to the engine bilge. With the PRV where it is I don't think there is a NRV in your system.

 

That just leaves the pressure switch and pump to be located somewhere accessible but out of your way.

[Steph H]

6 hours ago, Tony Brooks said:

In that case you don't need the white valve and pipework when you reposition it all.

 

The accumulator can go anywhere on the COLD system so look for odd lost space under double beds etc. It rarely needs attention. The PRV can be relocated to the hot side of the calorifier (where most people expect to find it) and the outlet piped into the engine room bilge or overboard.  Although the accumulator will act as an expansion vessel as well providing there is no non-return valve on the cold inlet to the calorifier it may dribble a bit so hence the outlet going to the engine bilge. With the PRV where it is I don't think there is a NRV in your system.

 

That just leaves the pressure switch and pump to be located somewhere accessible but out of your way.

OK thats great thank you.

 

Have been checking out your website and think it will be an invaluable resource

[Tony Brooks]

1 hour ago, Steph H said:

OK thats great thank you.

 

Have been checking out your website and think it will be an invaluable resource

Thanks

 

Please remember they are course notes and were expanded during the courses that I no longer run. For instance the water section does not mention expansion vessels, Remember that if you feel you would rather get one to one advice without the way forums go off topic I am always happy to provide it by email free of monitory charge. However my conditions allow me to rework the emails and publish them to help others, usually in Canal Boat magazine.

[AndrewIC]

On reflection I could only think of two potential reasons for the white valve, both suggested above. One is to decompress the water system without wasting water, which seems a bit over the top. The other is to drain the system, but that assumes another valve somewhere at the “other end” to let the water out - perhaps into a pumped bilge?