Adding a second bilge pump?

[Tony1]

1 hour ago, magnetman said:

You will need a wall plate tee for it 

 

https://www.ebay.co.uk/itm/122981629279

 

Of the correct size 

 

 

And PTFE tape for the thread. 

 

 

Thanks Mr M, and can I just check something- the expansion tank will fit on the female socket that points upwards in the pic, right? 

So I dont want to attach this sideways onto a wall right? Otherwide all the weight would be hanging off that joint.

Am I right in thinking I would want to screw this to the floor? 

 

[Tony Brooks]

1 minute ago, magnetman said:

Have you checked everywhere ? Quite often this item (accumulator/expansion vessel) will be in the same place as the water pump rather than beside the calorifier. 

 

You probably have checked but it seems worth asking. 

 

There is a problem with this. It looks like a Surecal calorifier and I think those have an NRV in the cold inlet. I it dos it will prevent anything close to the water pump from also acting as an expansion vessel.No NRV and it should be OK to do that.

2 minutes ago, Tony1 said:

 

 

Thanks Mr M, and can I just check something- the expansion tank will fit on the female socket that points upwards in the pic, right? 

So I dont want to attach this sideways onto a wall right? Otherwide all the weight would be hanging off that joint.

Am I right in thinking I would want to screw this to the floor? 

 

Yes & yes

[Tony1]

14 minutes ago, magnetman said:

Have you checked everywhere ? Quite often this item (accumulator/expansion vessel) will be in the same place as the water pump rather than beside the calorifier. 

 

You probably have checked but it seems worth asking. 

 

Over recent months I've had occasion to look in almost every nook and a lot of the crannies, and not seen anything like this. I would scour for it tomorrow, but tomorrow is going to be alternator belt tightening (or replacement) day, which is another job I've never tried before, so it would be realistic to expect a panicked question on here at around midday saying I think I've broken the alternator. I fear the fee for your professional skills could become monstrous. 

 

I did search in the water pump area too- that's sited under the front steps, and I recently fitted a plastic tray underneath it, as per Jen's idea. the plan is that if it leaks a shallow pool will form in the tray, and I put a water leak detector into the tray, with its alarm mounted on the side of the steps.

The water pump leaked two years ago and ruined the carpet and soaked the plywood floor, so I dont really trust water pumps any more, and I'm hoping I'll get a warning as soon the current one starts to leak. 

 

 

 

Edited January 14, 2023 by Tony1

[magnetman]

It is not always practical but a good way to avoid water pumps leaking is to mount them above the top of the water tank. The pump will still work normally but if any small leaks occur the result will be air in the water to the taps and not water in the boat. 

 

I only discovered this when I bought Dulcinea, my nuclear fallout bunker, a couple of years ago. Bloke who built the boat and fitted it for survival in the harshest of nuclear winters the likes of which have never been seen had worked it all out. You do NOT want water in the boat. It's basic. Good rule I think. 

Edited January 14, 2023 by magnetman
Edit to correct weight units

[ditchcrawler]

[magnetman]

I wonder what the difference between the two products is other than the price and the word "potable". A lot of people don't drink water out of the boat tank anyway. 

 

Is it going to be the rubber used for the diaphragm or just an arse covering insurance thing ?

[Tony1]

12 minutes ago, magnetman said:

I wonder what the difference between the two products is other than the price and the word "potable". A lot of people don't drink water out of the boat tank anyway. 

 

Is it going to be the rubber used for the diaphragm or just an arse covering insurance thing ?

 

16 minutes ago, ditchcrawler said:

 

Cheers Brian, and can I just check- the red model you showed in your earlier pic was I think a 2 litre one, and this is 12 litres.

I can imagine that the larger the tank is, the better it absorbs shocks- but what is the best size for a hot water system like on a boat?

 

ETA- are these inserts below the right ones to use if I want to avoid inserting plastic piping straight into the expansion tank?

 

https://www.screwfix.com/p/hep2o-smartsleeve-stainless-steel-push-fit-pipe-inserts-15mm-10-pack/3158f

 

 

26 minutes ago, magnetman said:

It is not always practical but a good way to avoid water pumps leaking is to mount them above the top of the water tank. The pump will still work normally but if any small leaks occur the result will be air in the water to the taps and not water in the boat. 

 

I only discovered this when I bought Dulcinea, my nuclear fallout bunker, a couple of years ago. Bloke who built the boat and fitted it for survival in the harshest of nuclear winters the likes of which have never been seen had worked it all out. You do NOT want water in the boat. It's basic. Good rule I think. 

 

Its an ingenious idea but at the moment I cant think of a place I could put the water pump that is above the tank, unless maybe I put it in the upper shelf of the sink cupboard.

Does it matter if its located 6 metres from the water pump? 

 

 

Edited January 14, 2023 by Tony1

[Tony Brooks]

28 minutes ago, magnetman said:

I wonder what the difference between the two products is other than the price and the word "potable". A lot of people don't drink water out of the boat tank anyway. 

 

Is it going to be the rubber used for the diaphragm or just an arse covering insurance thing ?

 

I will repeat what I explained a very few hours ago.  Non-potable products are designed to be used on combi-boilers and other sealed central heating systems that keep the boiler water separate from the tap water so can can and should use antifreeze and inhibitor, so  corrosion resistance of the steel shell is not so important. In potable systems there can be no corrosion inhibitor so the inside of the steel shell is coating with glass or a decent epoxy coating. If anyone is happy with a shorter shell life and rusty coloured tap water by all means use a non-potable one. Both work in the same way.

[Grassman]

23 hours ago, blackrose said:

The big rubber mat idea obviously won't help the OP as if I've understood correctly his problem is due to sunken steps in the deck. They're notorious for leaking into the engine space. 

 

My situation is exactly the same as the OP and the 2 rubber mats do help. In fact they work very well in preventing to 2 drain holes getting clogged up.

[Tony1]

On 14/01/2023 at 11:39, agg221 said:

Given the choice, I suspect all of us would rather have no water in our boats than some water. There is probably a sort of absolute point of 'too much water' which is relatively objective and measurable by sinking or damage to fixtures and fittings, followed by 'more water than I would like' which is where it comes in and makes a mess (we currently have that from the vent fitting in the bathroom and an annoying but unidentified source which is running down the engine bay sides a bit). Beyond that there is a law of diminishing returns, but where there is a practical fit and forget solution it is probably worth doing as reality dictates that anything which requires human intervention will eventually either be forgotten or circumstances will prevent it from being done, giving you consequences you would rather not have.

 

With regard to the specific question of a second bilge pump solution, there is a cost/benefit analysis to be done here. If it keeps the bilge dry enough by doing so that it makes a real difference then it is probably worth it against the cost of buying and installing it and the risk of it causing a further problem if a skin fitting gets broken off, which I would regard as minimal if you can tuck it in near a rubbing strip and it is well above waterline.

 

From my own experience, I would perhaps go further and use the second bilge pump to plumb any other definite, predictable sources of leakage in to. I used our boat as a base for a business trip in November, just an overnight stay as it was convenient for a meeting the next morning and gave me a chance to check on it. I was planning to change the fuel filters, but actually went on board to find a couple of inches of water across the entire stern section. Briefly, I was that highly effective bilge pump of a panicking man with a bucket) and I then spent several hours lifting floors and removing as much as I could with a sponge and bucket, and cursing the fact that this had happened in the cold and wet part of the year so drying it out properly was going to be extremely slow and difficult compared with the extended dry spell over the summer.

 

I then worked out what had happened. We had been out for a few days at the end of October. When we returned to the mooring we went through the usual series of actions, including a turn on the stern greaser to 'firm'. The stern shape on our boat does not make inspection of the stern greaser easy at all (you can't see below it) and the entry point for the grease tube is on the bottom. During his 'refurbishment' one of the corners which the PO had cut was not replacing the plastic tube, which being over 20yrs old had become brittle and split, so grease was not being pumped into the stern tube, but you couldn't see that because it was on the underside. The tube had therefore started to drip slightly, only about once every 30 seconds or so, so not obvious, but over the three weeks that had put about 4 gallons of water into the boat. There is a catch tub under the stern tube with a second bilge pump in it, but the pump had failed and the tub had overflowed, hence the water in the bilge. 4 gallons is not that much - annoying and messy but nothing more. It had not reached the level to trigger the main bilge pump which would have dealt with it if more had come in. I also moved the placement of the main pump so that it would trigger slightly earlier while I was at it (our boat has a slight V bottom and by moving some ballast around I could get it right to the bottom of the V).

 

We were not actually in danger of sinking as the main pump would have kicked in, but the boat is now damp over winter in a way that it would not have been and time has been spent fixing that rather than things I would rather have been fixing, and we have to have the floors up which is not ideal for moving around by walking over the ballast (particularly during a night-time trip to the heads where there is a serious risk of stubbed toes!)

 

The relevance of this is that if I was doing what Tony is proposing I would also add a catch pot under the stern gland, where the water is unlikely to contain any debris, and plumb that with a pipe part way up the container, running down to the catch pot under the steps which contained the second bilge pump. That way, a leak on the stern gland would be noticeable because the catch pot would contain water up to the level of the drain pipe, and I would have a second level of protection because it would be dealt with by the secondary pump, unless that failed in which case the primary pump would deal with it, and there would be a lot less mess to deal with if it starts to weep.

 

Alec

 

 

Just a belated apology for not acknowledging this helpful reply earlier, at the time whether I was in the middle of sorting things out and overlooked a few posts in my haste.  

 

I was reading some of the posts here trying to confirm a couple of things

 

1. what was the recommended size for an expansion tank (I remember both 2 litre and 12 litre examples being shown)

2. what is the significance of the presence or absence of a non-return valve (ie if there's no NRV, does that mean I dont want to fit an expansion vessel?)

 

 

On your point above, I don't seem to have a traditional stern gland as such- I think someone who saw my stern tube a long time ago referred to it as a 'volvo' type, but my memory could be dodgy on that. The prop shaft runs right over the bilge sump, so my hiope would be that if it leaks, the main bilge pump will catch that.

The prop shaft has never felt damp as best I can tell, so I dont think its been the source of any leaks- but this reminded me that whatever type it is, it will need periodic inspection and maintenance, so I will try to take a few pics later and then find out what sort it is, and what maintenance it will need. 

 

 

[rusty69]

As I understand it, a NRV at the input to a calorifier is to prevent any hot water from the calorifier mixing with cold further back up the pipe. The shorter the distance between calorifier and tap, the greater the need for a NRV. 

 

If you don't have a NRV, your accumulator will, to a certain extent act as an an expansion vessel. The expansion vessel is required to prevent damage to the calorifier when the water expands due to heating, and also prevent the PRV from continually operating. 

[rusty69]

I think when I fitted an expansion vessel a few years ago, I simply used the calorifier volume to calculate the required vessel size based on the amount the water was likely to expand when heated. 

[ditchcrawler]

3 hours ago, Tony1 said:

 

On your point above, I don't seem to have a traditional stern gland as such- I think someone who saw my stern tube a long time ago referred to it as a 'volvo' type, but my memory could be dodgy on that. The prop shaft runs right over the bilge sump, so my hiope would be that if it leaks, the main bilge pump will catch that.

  

You do need to find out as some require silicon grease added at regular intervals which you may have already exceeded 

[cuthound]

3 hours ago, ditchcrawler said:

You do need to find out as some require silicon grease added at regular intervals which you may have already exceeded 

 

Every 100.hours for my Radiche gland and it's Vetus predecessor.

[Tony1]

 

Cheers guys, I've started a new thread to ask about this gland, as it might then be easier for any future searchers to find it. 

 

 

 

 

 

[Tony1]

 

For completeness, and in case any future readers have a similar steps and thus a drain blockage risk to think about, this is what I've put on the lowest step to prevent leaves gathering around the drain hole (which is I think 0.75 inches wide).

It's a bit of a bodge as there are only two M6 bolts holding it, but it's stainless steel so it should stand up to at least some knocks from passing feet, and it can be stood on without breaking. 

The cut through the front is to allow water to drain through at the lowest level of the step.  

It wont get a test until October, but I plan to let the leaves accumulate as long as I reasonably can (assuming I'm aboard every night), and see how it gets on in the sort of worst case scenario of being left alone for two months at the worst time of year for leaf blockages. 

The theory is that even if sodden leaves and blown soil particles pile up around it to a depth of an inch more, there should still be enough of a gap for the water to drain, and it will certainly be harder to block than the drain hole was.  

It came in a two pack so if it works well, I'll do a more tidy job and replace it with the second one: 

 

https://www.amazon.co.uk/dp/B09MLWN2QN?psc=1&ref=ppx_yo2ov_dt_b_product_details

 

I think the plastic mesh type matting with numerous large holes sounds a good idea, as well, but I'll see how this goes initially. 

 

Edited February 3, 2023 by Tony1

[Grassman]

My two rubber mesh type mats I referred to (one on top of the other) have worked well for years. I chose this method on the basis that it protected the holes from being 'plugged' directly by leaves, and even if the whole step gets completely covered by leaves the rainwater will work it's way through them and will find the drain holes. I'm not sure I need to use 2 mats but I think doing so helps the water permeate through them to the bottom.

 

These are the mats I'm talking about

 

https://www.gclproducts.co.uk/p/rubber-surfacing/rubber-play-surfaces/rubber-grass-mats-23mm/?attribute_pa_pegs-ties=not-included&gclid=CjwKCAiAxP2eBhBiEiwA5puhNbz8DCgmDhVKkzIRldiqIP0YdqCYr5SllHi2LBSVeOk45PEjBwarcxoCTDcQAvD_BwE

 

I think your method will probably solve your issue but as you say, the mats idea could be a solution if not.

[Tony1]

On 14/01/2023 at 15:41, Tony Brooks said:

Two f the white pipes will run to the engine, one of the pairs horizontally opposite to each other. The other pair will run to where they join the central heating pipework.

 

 

 

The pipe marked A is probably the PRV vent pipe, so where does it go to.  It is likely to drip whenever the calorifier is heated.

 

Hi Tony, I wonder if I can just check on something? 

I can't find a mention of which specific pipe I need to fit the expansion vessel on?

 

Is it the pipe marked A above with the PRV on it?

Or is it the main hot water outlet? And if its that one, would it be ok to fit the expansion vessel after the mixing valve? 

 

I've now got a 12 litre potable hot/cold vessel, plus a fitting kit from Screwfix, so I'm going to get hold of some suitable piping and joints etc, and have a go at fitting it in the next few weeks. 

 

 

 

[Tony Brooks]

1 hour ago, Tony1 said:

 

Hi Tony, I wonder if I can just check on something? 

I can't find a mention of which specific pipe I need to fit the expansion vessel on?

 

Is it the pipe marked A above with the PRV on it?

Or is it the main hot water outlet? And if its that one, would it be ok to fit the expansion vessel after the mixing valve? 

 

I've now got a 12 litre potable hot/cold vessel, plus a fitting kit from Screwfix, so I'm going to get hold of some suitable piping and joints etc, and have a go at fitting it in the next few weeks. 

 

I very much doubt it. It goes in the hot domestic water pipe between the calorifier and the rest of the domestic hot water system. It will be close to the top of the calorifier, where the hottest water will be. Before any mixing valve.

 

I think A  is probably a heating coil pipe.

Edited February 14, 2023 by Tony Brooks

[Tony1]

2 hours ago, Tony Brooks said:

 

I very much doubt it. It goes in the hot domestic water pipe between the calorifier and the rest of the domestic hot water system. It will be close to the top of the calorifier, where the hottest water will be. Before any mixing valve.

 

I think A  is probably a heating coil pipe.

 

Thanks very much Tony.

The hot water initially comes out of the calorifier in a flexible metal hose, which feeds into the mixing valve.

So it looks like I'm going to have to fit some 15mm pipe to the end of that metal hose to take the hot water into the expansion vessel (which will be sited about 18 inches away from the hot water outlet of the calorifier), and then I can fit the mixer device after the hot water supply comes out of the expansion vessel.

If you don't mind me asking a quick follow up- is it likely that air will get into the hot water supply or the calorifier during this, and is there anything I should do to reduce that issue?

 

PS- as a warning note to other folks who are poor at DIY, I wanted to add that I talked about this with a boater who I considered mechanically competent and pretty knowledgeable, and he said it wasn't a significant problem that my calorifier has no expansion vessel. 

It just goes to show- when talking to other boaters about boating jobs- even those boaters who've been living aboard for years and who seem adept at DIY jobs- you still cant take their technical advice at face value.

I would always check with the experts here. 

 

 

Edited February 14, 2023 by Tony1

[rusty69]

8 minutes ago, Tony1 said:

PS- as a warning note to other folks who are poor at DIY, I wanted to add that I talked about this with a boater who I considered mechanically competent and pretty knowledgeable, and he said it wasn't a significant problem that my calorifier has no expansion vessel. 

It just goes to show- when talking to other boaters about boating jobs- even those boaters who've been living aboard for years and who seem adept at DIY jobs- you still cant take their technical advice at face value.

I would always check with the experts here. 

Its probably less of a problem if you have an accumulator and no NRV in the feed to the calorifier.

[Tony1]

1 minute ago, rusty69 said:

Its probably less of a problem if you have an accumulator and no NRV in the feed to the calorifier.

 

I did explain to the guy that I dont have an accumulator anywhere, but he was still quite dismissive about the need for an expansion vessel. 

I think Tony B himself said that there was an alternative to fit an expansion vessel in the cold supply to the calorifier (with no NRV being present). 

I'm pretty sure I have no NRV in the cold supply, so if I can confirm that somehow (e.g. without having to remove the shower tray and check underneath), then I might consider fitting the expansion vessel in the cold supply, e.g. under the sink), which will be easier than putting it into the hot water out from the calorifier. 

If I were to fit the expansion vessel that way, does it matter where in the cold supply it goes?

Is it ok to put it anywhere after the water pump?

 

 

[rusty69]

5 minutes ago, Tony1 said:

 

I did explain to the guy that I dont have an accumulator anywhere, but he was still quite dismissive about the need for an expansion vessel. 

I think Tony B himself said that there was an alternative to fit an expansion vessel in the cold supply to the calorifier (with no NRV being present). 

I'm pretty sure I have no NRV in the cold supply, so if I can confirm that somehow (e.g. without having to remove the shower tray and check underneath), then I might consider fitting the expansion vessel in the cold supply, e.g. under the sink), which will be easier than putting it into the hot water out from the calorifier. 

If I were to fit the expansion vessel that way, does it matter where in the cold supply it goes?

Is it ok to put it anywhere after the water pump?

 

 

Pretty sure you can fit it anywhere after the pump.

 

But yes, if you have no NRV and no accumulator and no expansion vessel, you are reliant on the PRV dumping the expanding water, which isn't good practice.

Edited February 14, 2023 by rusty69
clarification

[Tony Brooks]

31 minutes ago, Tony1 said:

 

Thanks very much Tony.

The hot water initially comes out of the calorifier in a flexible metal hose, which feeds into the mixing valve.

So it looks like I'm going to have to fit some 15mm pipe to the end of that metal hose to take the hot water into the expansion vessel (which will be sited about 18 inches away from the hot water outlet of the calorifier), and then I can fit the mixer device after the hot water supply comes out of the expansion vessel.

If you don't mind me asking a quick follow up- is it likely that air will get into the hot water supply or the calorifier during this, and is there anything I should do to reduce that issue?

 

PS- as a warning note to other folks who are poor at DIY, I wanted to add that I talked about this with a boater who I considered mechanically competent and pretty knowledgeable, and he said it wasn't a significant problem that my calorifier has no expansion vessel. 

It just goes to show- when talking to other boaters about boating jobs- even those boaters who've been living aboard for years and who seem adept at DIY jobs- you still cant take their technical advice at face value.

I would always check with the experts here. 

 

 

 

The reason I said between the calorifier and mixing valve is because I don't know for sure what happens to the mixing valve with a higher pressure on the tap side, but the expansion vessel should still work if fitted after the mixing valve.

[Tony1]

14 minutes ago, rusty69 said:

Pretty sure you can fit it anywhere after the pump.

 

But yes, if you have no NRV and no accumulator and no expansion vessel, you are reliant on the PRV dumping the expanding water, which isn't good practice.

 

Thanks Rusty.

Thing is, I don't think I've mentioned until today that I have no accumulator on the cold water supply. And so at the moment my water pump switches on and off every few seconds if I run the cold water tap slowly.

 

So maybe my expansion vessel can prevent that issue happening- and also help to reduce stress in the calorifier- if I put it in the right place on the cold supply?  

And you're saying the right place to help with both issues would be anywhere after the water pump, right? 

 

I think Tony said this was not as good a solution as an expansion vessel in the hot water supply, but at least it would save me having to get a second one....

 

Edited February 14, 2023 by Tony1