Jump to content

Plumbing! Seeking general advice...


Featured Posts

Hi all, 

 

On to the plumbing stage of my fit-out... I've drawn up the attached diagram which is my proposed system, I'm new to this so I'm seeking general advice from people who know better as to whether I've overlooked anything important any pointers on best practices etc. would also be much appreciated.

 

There will be a 1L accumulator fitted after the pump.

 

The pump is a Jabsco Par-Max 2.9, I was going to buy a Cointra 11 water heater which has a similar (very slightly less) flow rate to the pump, would this be a good choice or are there other things I need to consider?

 

All feedback appreciated. Thank you in advance! 

Plumbing-01.jpg

Link to comment
Share on other sites

12 minutes ago, Detling said:

You show hot water pipes but no source of hot water.

The hot water comes from the water heater, it’ll be a instant gas water heater I am considering the Cointra CPA11. I haven’t shown the gas lines. 

Link to comment
Share on other sites

The source of hot water appears to be labelled 'water heater'.

 

Generally it looks OK.  I would fit seive, aka filter, near the tank. An appliance isolation valve before the water heater would enable you to remove it for repair or service without losing all water service.  I think a 1 l accumulator is too small.  At least 2.5 l needed.

You also need drain valves so you can easily get all the water out when it is brass monkeys' outside and you want to leave the boat for a while.

N

Link to comment
Share on other sites

9 minutes ago, BWM said:

I'm not sure having the pump mid system is going to help, it is normmulator al to have it close to the tank c/w accumulator. 

Last two boats I have had the pump and accumulator have been near the back of the boat with the tank at the front. Works fine.

 

Also go for the bigger accumulator saves the pump coming on when the bog is flushed mine is 5L

Edited by Loddon
Link to comment
Share on other sites

5 minutes ago, BEngo said:

The source of hot water appears to be labelled 'water heater'.

 

Generally it looks OK.  I would fit seive, aka filter, near the tank. An appliance isolation valve before the water heater would enable you to remove it for repair or service without losing all water service.  I think a 1 l accumulator is too small.  At least 2.5 l needed.

You also need drain valves so you can easily get all the water out when it is brass monkeys' outside and you want to leave the boat for a while.

N

Amazing, thank you. 
 

What is the benefit of a larger accumulator? Is it do with the water heater? 
 

Drain valves, amazing! Where would you put them, how would they work, would you need a space inside the bilge to put a tub or something to catch the drained water? 
 

I was going to fit valves before each outlet for maintenance but putting one in front of the heater is an excellent idea, thank you. 

Link to comment
Share on other sites

1 minute ago, Loddon said:

Last two boats I have had the pump and accumulator have been near the back of the boat with the tank at the front. Works fine.

 

I pondered this, couldn’t think of a logical reason why the pump being near the tank would make any difference to it... 

Link to comment
Share on other sites

14 minutes ago, WillCful said:

What is the benefit of a larger accumulator?

It can feed stuff like a loo flush without the pump having to cycle.  The larger the accumulator, the less the pump cycles.

 

For that matter... you haven't shown a feed to the loo.

Link to comment
Share on other sites

1 minute ago, WotEver said:

It can feed stuff like a loo flush without the pump having to cycle.  The larger the accumulator, the less the pump cycles.

 

For that matter... you haven't shown a feed to the loo.

Haha, loo will be composting... never encountered one before though, I’m keeping the old thetford in reserve... 

 

surely the pump will need to cycle to top up the pressure in the accumulator once it’s emptied? 

Link to comment
Share on other sites

Just now, WillCful said:

surely the pump will need to cycle to top up the pressure in the accumulator once it’s emptied? 

Yup, but short usage of water won't empty it.

1 minute ago, WillCful said:

loo will be composting...

Oh, here we go...

1 minute ago, WillCful said:

I’m keeping the old thetford in reserve... 

It'll need a water feed unless it's one with a separate flush tank.

Link to comment
Share on other sites

2 minutes ago, WotEver said:

Yup, but short usage of water won't empty it.

Oh, here we go...

I see... so the pressure in the tank stays the same even when it’s not full? And it will only refill once fully empty? 
 

Thought so... let’s stay on topic!! ?

Edited by WillCful
Link to comment
Share on other sites

1 hour ago, WillCful said:

Haha, loo will be composting... never encountered one before though,

Don't forget to get your builder to build in a space for the storage of 6-months worth of faeces in open buckets so it can compost properly before you dispose of it.

 

It is illegal to discharge any sewage into the marina and all sea toilet seacocks should be closed when berthed in a BWML marina to ensure there is no accidental discharge. Consider a holding tank if using a sea-going craft for residential purposes, rather than face the possible prosecution by the Environment Agency. Elsan disposal points are available for portable toilets systems, and do not empty cassettes into the marina or toilets. Even if you have a pump out fitted, it is worth considering a ‘cassette’ style toilet for the winter months as marinas do freeze over. Currently, composting toilets are not permitted in BWML marinas under the current waste transfer laws.

 

 

Link to comment
Share on other sites

14 minutes ago, Alan de Enfield said:

Don't forget to get your builder to build in a space for the storage of 6-months worth of faeces in open buckets so it can compost properly before you dispose of it.

Ha, I wish I could afford to pay someone to build my boat for me. 

Link to comment
Share on other sites

22 minutes ago, Alan de Enfield said:

Don't forget to get your builder to build in a space for the storage of 6-months worth of faeces in open buckets so it can compost properly before you dispose of it.

 

It is illegal to discharge any sewage into the marina and all sea toilet seacocks should be closed when berthed in a BWML marina to ensure there is no accidental discharge. Consider a holding tank if using a sea-going craft for residential purposes, rather than face the possible prosecution by the Environment Agency. Elsan disposal points are available for portable toilets systems, and do not empty cassettes into the marina or toilets. Even if you have a pump out fitted, it is worth considering a ‘cassette’ style toilet for the winter months as marinas do freeze over. Currently, composting toilets are not permitted in BWML marinas under the current waste transfer laws.

 

 

Not quite as Alan would like to make out see https://canalrivertrust.org.uk/enjoy-the-waterways/boating/boating-blogs-and-features/boating-team/game-of-thrones-boat-toilet-waste-disposal

Capture.JPG

Edited by ditchcrawler
Link to comment
Share on other sites

1 hour ago, WillCful said:

Haha, loo will be composting... never encountered one before though, I’m keeping the old thetford in reserve... 

 

surely the pump will need to cycle to top up the pressure in the accumulator once it’s emptied? 

Wow this place really is becoming toxic to new members. Sorry about that, unfortunately some people on here prefer to look for their pet grievances and reasons to criticise, rather than actually spending 15 seconds reading what you have written. Sad.

 

Anyway, back on topic I think you scheme is mostly fine. Water is water, just needs to be connected up via pipes, not hard. The boat we used to borrow had the water tank at the front and the pump right at the back near the calorifier. Which seemed a bit odd to me, but it worked fine. Our current boat has the pump a couple of feet from the tank outlet. Also works fine!

 

The purpose of the accumulator is to prevent the pump switching on and off rapidly when the demand is less than the pump can provide, which is probably bad for pump longevity. There is no “right size” but larger is better, up to a point. If the accumulator is very small the pump will cycle fast and also it means the pump may cut in annoyingly due to eg slight thermal contraction when things cool down at night. It is annoying to hear the pump cut in just as you are dozing off. So perhaps a somewhat larger accumulator would be advisable. On the other hand, it’s not an expensive item so try your 1l one and if it turns out to be annoying, get a bigger one!

 

Most pumps seem to have a strainer built in to the inlet, so I’m not sure you need a separate one. I suppose it may depend on the type of tank you have - integral and thus made of mild steel, or stainless steel or even plastic, neither of which should be prone to getting any “bits” in them. We have a stainless steel tank and a strainer but I’ve never found the slightest spec in it.

 

Composting toilets are generally ridiculed by those who have never tried them, whereas those who have actually tried them seem to think they are good.

 

  • Greenie 1
Link to comment
Share on other sites

11 hours ago, WillCful said:

Amazing, thank you. 
 

What is the benefit of a larger accumulator? Is it do with the water heater? 
 

Drain valves, amazing! Where would you put them, how would they work, would you need a space inside the bilge to put a tub or something to catch the drained water? 
 

I was going to fit valves before each outlet for maintenance but putting one in front of the heater is an excellent idea, thank you. 

Drain valves are there to let the water out of the pipes so it does not freeze and burst them. You need one at every low point in the system. Look like this:

https://www.jtmplumbing.co.uk/pipe-fittings-c433/compression-valves-15mm-28mm-c41/jtm-drain-off-type-b-p903/s905?utm_source=google&utm_medium=cpc&utm_term=jtm-drain-off-type-b-15mm-size-15mm-size-15mm-bfdoctb-15na&utm_campaign=product%2Blisting%2Bads&cid=GBP&gclid=EAIaIQobChMIl4Teu6b-6QIVg7HtCh3BsQ-SEAQYBCABEgKp_PD_BwE

You need to be able to get a  tub under them.

  By good design you can arrange the pipes so they drain naturally to one or two places, which makes it easy to drain off for winterising.  Most important item to drain will be the water heater.  They do not like frost.  Plastic pipes stand freezing, but the joints don't.  Keep the pump as low in the boat as possible because the water usually only freezes at the top, so the pump won't freeze up if there is still some water in it.

 

N

Link to comment
Share on other sites

11 hours ago, Loddon said:

Last two boats I have had the pump and accumulator have been near the back of the boat with the tank at the front. Works fine.

 

Also go for the bigger accumulator saves the pump coming on when the bog is flushed mine is 5L

This makes more sense than installing the pump in the middle of the system, if only to ensure the system is drained efficiently. 

11 hours ago, WillCful said:

I pondered this, couldn’t think of a logical reason why the pump being near the tank would make any difference to it... 

A waste of materials and more importantly it can only complicate draining the system for maintenance or repair. It should be fitted at one end of the system, if the tank is at the bow there is an argument to fit the pump at the back end of the circuit for both voltage drop or ability to drain completely. Personally I prefer it fitted next to tank, minimal air in pipework if run dry, one valve to isolate to work on pump, minimal fittings, etc. 

Link to comment
Share on other sites

1 minute ago, BWM said:

This makes more sense than installing the pump in the middle of the system, if only to ensure the system is drained efficiently. 

When I say at the back one is not right at the back.

It is between the kitchen and bathroom so the outlet from the pump went to a T feeding in two directions.

 

It really doesn't matter where the pump is in the layout

Link to comment
Share on other sites

11 hours ago, BWM said:

I'm not sure having the pump mid system is going to help, it is normal to have it close to the tank c/w accumulator. 

 

Yes. If the pump has to be so far from the tank then the low pressure side of the system (from tank to pump) should be plumbed in 22mm dia pipe. 

 

The pump should have a strainer fitted and it should be plumbed with short lengths of good quality hose to deal with the vibrations (not garden hose) not direct to rigid pipe. The Jabsco pump should have come with clip in hosetail fittings.

13 minutes ago, Loddon said:

 

 

It really doesn't matter where the pump is in the layout

 

I think it does if it's only plumbed in 15mm pipe on the low pressure side as it can struggle to get enough water through.

Edited by blackrose
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.