secondery loop

[nb Innisfree]

There have been several posts while I was writing mine and up to this and I was beaten to this non 'solution' along the way. I/we are putting ideas forward for rjection or refining to a workable solution. Whilst you are diverting the pump will be delivering back to the calorifier so it will not reach the cold tank. There is a danger then that hot could be supplied to a cold tap opened at the same time as somebody has since pointed out.

 

There is probable as mush plumbing involved as in yours with an extra pump?

 

Yes it could result in hot into pump inlet and not back into tank if accumulator depletes and switches pump on. My first suggestion that it could be returned direct to tank would be safer but involves more work to achieve. Perhaps an auto scald shut off as fitted in some showers? believe they fit in shower heads, could be fitted between tap and pump inlet and close before hot water reaches scald temp (47C?) Yes it is starting to make my simple solution a little more complex but not much and it is elegant

[nb Innisfree]

I know nothing of auto shut off valves and how they would fare in a boat pressurised system sounds like the sort of knowledge the poster needs

 

Screwfix do an auto shut off valve part no 71039-96 exposed or 41592-96 concealed, adjustable 7, 15 or 30 seconds, bit pricey tho £70 Plumbers merchants prob do an alternative.

Edited October 28, 2009 by nb Innisfree

[nb Innisfree]

There have been several posts while I was writing mine and up to this and I was beaten to this non 'solution' along the way. I/we are putting ideas forward for rjection or refining to a workable solution. Whilst you are diverting the pump will be delivering back to the calorifier so it will not reach the cold tank. There is a danger then that hot could be supplied to a cold tap opened at the same time as somebody has since pointed out.

 

There is probable as mush plumbing involved as in yours with an extra pump?

 

What would be a suitable pump? single feed shower pump or standard pump maybe? return would need to go to near top of calorifier not to bottom as it would dilute hot water, perhaps an Essex fitting (not sure if that is the right name) the one that goes into top of calorifier to draw off HW but used in this situation to return HW.

 

Starts to make a simple extra pump less simple. Whichever solution used depends on ease of installation in this particular boat.

 

 

i think this would need much more plumbing and a valve on every tap and plumb back from every tap to befor the presure pump on the cold feed? is this what you have in mind i am a little confused.

 

Yes you've got it. Would need a valve for kitchen tap and one valve for bathroom (would cover shower and any taps)

[Phil Ambrose]

Our boat uses canal/river/sea water to flush the loo.

 

Yup mine too

 

Phil

[Roger Gunkel]

Am I the only one to think of the obvious?

 

All this intense discussion about recirculating water that would other potentially be wasted waiting for the hot! Why not just put in a demand water heater, that only gives you hot water when the hot tap is turned on, rather than storing it in the calorifier, to mix with the cold input, reducing the heat further.

 

As regards electric flushing toilets, or using grey water etc, the most simple, cheapest and most efficient is to put in a manually flushed chemical toilet. If you really want to save water even more, keep the trap open and pee and poo through the hole, needing a minimum of water as there is nothing to wash off the bowl.

 

Roger

[Chertsey]

i have mesured it.

i know my spelling is realy bad but please read what i print.

How many litres did you say you are you wasting each time?

How many metres of 15mm pipe does it take to hold a litre of water? (someone will know)

 

When washing up, I run the water into the kettle - but we have two kettles, so that overcomes the problem of one being out of commission.

 

If you are waiting for the shower to run hot so that you can stand under it, then you really are wasting water.

Here's what we do. Get a 2 gallon bucket. Run the shower into it. It'll run cold first, then (from our calorifier) very hot, resulting in a bucketful (or less) of comfortably hot water. Wash and rinse face in water from bucket. Use water in bucket to soap and scrub body. Tip remainder of bucket over head. Shampoo hair. Then turn shower back on (using mixer tap) and rinse.

[nb Innisfree]

It seems to me that the whole point of this thread is to think of ideas to achieve the OP's goal, not to pour cold? water on it and suggest that it's a non starter. All he's trying to do is try and adapt a well known and used system to work on a boat. Electric flushing toilets on a boat, what's wrong with that? Historically if we hadn't tried against all the odds and advice to try and make something awkward and difficult to operate efficiently (horseless carriages? never work too complicated and anyway what's wrong with a horse?) we would still be in the trees.

 

Come on try to stay positive

 

Got that off my chest

[nb Innisfree]

How many litres did you say you are you wasting each time?

How many metres of 15mm pipe does it take to hold a litre of water? (someone will know)

 

When washing up, I run the water into the kettle - but we have two kettles, so that overcomes the problem of one being out of commission.

 

If you are waiting for the shower to run hot so that you can stand under it, then you really are wasting water.

Here's what we do. Get a 2 gallon bucket. Run the shower into it. It'll run cold first, then (from our calorifier) very hot, resulting in a bucketful (or less) of comfortably hot water. Wash and rinse face in water from bucket. Use water in bucket to soap and scrub body. Tip remainder of bucket over head. Shampoo hair. Then turn shower back on (using mixer tap) and rinse.

 

We just turn on shower and step straight in to hot water and have a 2 gall or less shower, done. No buckets or waiting for water to run hot. How do we do it? through efficient layout of plumbing system. I appreciate some are stuck with what they have and may be happy with that. A well designed shower is the most efficient and economical method of washing the human body. OP is just trying to optimise things.

Edited October 28, 2009 by nb Innisfree

[DHutch]

We only have a 80gal tank (about 1/3 the size of a 1000L one) and its certanly something i have thought about.

- Even with well lagged pipes they dont take long to loose there heat and become warm, then it is all lost water running it through.

- If running a sinkfull then as the waters usally 80c+ you can indeed use the running through water as your cold, but not for showers or when you want a running hot tap for rinsing dirty hands etc.

 

The way i would implement it would be to have a loop where by the end of the hot supply goes back to the calorfier, in at the bottom, via a nrv.

- Then you just need to circ it using a low presure impellor type pump (or any other pump, but it only has to over coe the nrv) when you want to use the tap. Or even, when the engines running (almost infinate free heat), you could run it all the time.

 

JOb done...?

 

Doesnt solve the same problem for when your using the gas heater becuase your not boating however, which typical it when im being even more fugal with water (because your not passing taps) and im not sure i would want to be running hot/warm return water into the paloma which relies on a cold feed.

 

In the end, and up to now, ive not worries enough about it to over come the activation energy required. However i watch this space with interest.

 

 

Daniel

[nb Innisfree]

In my earlier post I suggested water should return to top of calorifier but as Dhutch says it can return via the bottom between the calorifier and NRV

[DHutch]

We just turn on shower and step straight in to hot water and have a 2 gall or less shower, done. No buckets or waiting for water to run hot. How do we do it? through efficient layout of plumbing system. I appreciate some are stuck with what they have and may be happy with that. A well designed shower is the most efficient and economical method of washing the human body. OP is just trying to optimise things.

Clearly having very short runs is the way forward. As said before , if you kitchen and bathroom are back to back, calorfier in the middle, your already well ahead of the game.

- However it rair for the calorifer to be other then in or close to the engine/engineroom. Then a room or two, then the bathroom, then kitchens often forward of that even. Certainly whatever you layout, by the time you have kitchen/shower&bath/guessroomsink/a-an-other sink then its all over.

 

 

Daniel

[nb Innisfree]

Clearly having very short runs is the way forward. As said before , if you kitchen and bathroom are back to back, calorfier in the middle, your already well ahead of the game.

- However it rair for the calorifer to be other then in or close to the engine/engineroom. Then a room or two, then the bathroom, then kitchens often forward of that even. Certainly whatever you layout, by the time you have kitchen/shower&bath/guessroomsink/a-an-other sink then its all over.

 

 

Daniel

 

I think it's better on the whole to have long runs from engine to calorifier rather than the reverse as this permits cal to be placed ideally, prob 2 or 3 smaller cals instead of one. Long insulated runs from engine deduct very little from heating efficiency. We have two cals of 50lt each, one is 25' from engine, the other 40' and find no probs with heating them.

[DHutch]

I think it's better on the whole to have long runs from engine to calorifier rather than the reverse as this permits cal to be placed ideally, prob 2 or 3 smaller cals instead of one. Long insulated runs from engine deduct very little from heating efficiency. We have two cals of 50lt each, one is 25' from engine, the other 40' and find no probs with heating them.

Maybe, although you do then end up with a really very very large cooling loop for the engine, lots of coolent needed, and more to go wrong prehaps.

[nb Innisfree]

Maybe, although you do then end up with a really very very large cooling loop for the engine, lots of coolent needed, and more to go wrong prehaps.

 

Gives handy aux cooling if req on river etc. tho never needed it yet. We can get away with large loop in the summer but have to watch in winter as rads are on same circuit so we preheat with mikuni to give warm engine on start up which benefits engine. This together with SF stove allowing some rads to be turned off, enables engine to quickly reach optimum temp and maintain it. As it has turned out length of loop gives enough resistance to engine water pump to prevent overcooling but not too much to prevent cal heating up. Final engine warmup is helped by having large alternator loading it.

[Timleech]

Another option to consider - use a smaller bore pipe.

10mm pipe holds less than half the volume of the usual 15mm, and can carry perfectly adequate flows for washbasins etc.

 

Tim

[number four]

Another option to consider - use a smaller bore pipe.

10mm pipe holds less than half the volume of the usual 15mm, and can carry perfectly adequate flows for washbasins etc.

 

Tim

 

this would be a prob as you would need longer to get the bucket etc full also the surface area to volune of water is greater so the water cools faster on rute.

 

some great discusion since i last loged on thanks every one.

 

to date for the options i have avalable to me concidering personal secomstances i think a loop with cerculating pump and nonretern valve.

 

any other options for the switchig?

[blodger]

this would be a prob as you would need longer to get the bucket etc full also the surface area to volune of water is greater so the water cools faster on rute.

 

some great discusion since i last loged on thanks every one.

 

to date for the options i have avalable to me concidering personal secomstances i think a loop with cerculating pump and nonretern valve.

 

any other options for the switchig?

Many of us carry around a spare water pump as a result of having experienced problems and having to effect repairs and realising how lost you are without the availability of water.

Your innovation is a good way of using the spare to some good but one would have to bypass the pressure switch and use it as 'on demand'. So that it can still be used as a spare it would necessitate shut off valves at each end so it could be quickly taken out of circuit, in addition.

What you are doing is returning the pipe load of water to your first hot tap where you put the pump across the loop and back to the calorifier.

I would use a relay to operate the pump so that you can make do with simple bell pushes that could be inset posh brass one to actuate the 'bypass' near each hot tap.

The benefits, in terms of saving water, depend on the first hot tap being far from the calorifier. It will not be instant hot water if there is a fair bit of piping to the next or subsequent taps.

So the cost is a couple of Ts, a couple of check valves, a bit of pipe, bell pushes, a relay and appropriate wiring/conduit. That is if the cost of a duplicate water pump can be ignored.

I would not do it for my set up for the reasons on the thread. Your setup/plans will be different so give it a go and let us know if you are satisfied.

[blodger]

Forgot plus the essential non return valve

[number four]

Many of us carry around a spare water pump as a result of having experienced problems and having to effect repairs and realising how lost you are without the availability of water.

Your innovation is a good way of using the spare to some good but one would have to bypass the pressure switch and use it as 'on demand'. So that it can still be used as a spare it would necessitate shut off valves at each end so it could be quickly taken out of circuit, in addition.

What you are doing is returning the pipe load of water to your first hot tap where you put the pump across the loop and back to the calorifier.

I would use a relay to operate the pump so that you can make do with simple bell pushes that could be inset posh brass one to actuate the 'bypass' near each hot tap.

The benefits, in terms of saving water, depend on the first hot tap being far from the calorifier. It will not be instant hot water if there is a fair bit of piping to the next or subsequent taps.

So the cost is a couple of Ts, a couple of check valves, a bit of pipe, bell pushes, a relay and appropriate wiring/conduit. That is if the cost of a duplicate water pump can be ignored.

I would not do it for my set up for the reasons on the thread. Your setup/plans will be different so give it a go and let us know if you are satisfied.

 

i think using relay and simple switch is a good idear i was thinking something from maplins small an descreat.

my pipe run will be a loop to pass all taps etc with a short 0.5m or less branch of to each tap so when pump it used it charges the hole system with hot

for the electrical minded how simple would it be to use a adjustable timed switch

ie: press once to start a timed run say 20seconds then system resets till next time?

also any recomendations for the pump?

[nb Innisfree]

Forgot plus the essential non return valve

 

In the past I have considered a fishtank pump, low consumption and able to take 60c+ IIRC

 

For switch a 230v pnuematic press button, the type used in entrance halls in flats They can be adjusted for time delay

Edited October 29, 2009 by nb Innisfree

[number four]

In the past I have considered a fishtank pump, low consumption and able to take 60c+ IIRC

 

arnt most of them designed to run under water for cooling

 

i thought this might work

http://www.acs-solarsystems.com/Solar_Pumps.htm

 

In the past I have considered a fishtank pump, low consumption and able to take 60c+ IIRC

 

For switch a 230v pnuematic press button, the type used in entrance halls in flats They can be adjusted for time delay

 

that switch is an eligant idear will it run on 12v?

Edited October 29, 2009 by number four

[Guest]

I guess I can't really get worked up about the way you are. If you are really talking about waste, then how are you accounting for the electricity in running pumps, or energy in manufacturing extra pipe, fittings, pumps and circuits.

 

In reality, you could save far more water by washing your boat once less per year.

 

Richard

 

(On reflection, if we washed Tawny Owl once less per year, she'd never get washed at all...)

In my case, that would mean it would never get washed

[nb Innisfree]

arnt most of them designed to run under water for cooling

 

i thought this might work

http://www.acs-solarsystems.com/Solar_Pumps.htm

 

 

 

that switch is an eligant idear will it run on 12v?

 

Pump sound just the job, would also make a nice low consumption CH circulator.

 

Switch would be ok on 12v at that low current. They are readily available at electrical suppliers I think.

[number four]

Pump sound just the job, would also make a nice low consumption CH circulator.

 

Switch would be ok on 12v at that low current. They are readily available at electrical suppliers I think.

 

so it looks like we have a working design

it will be next spring befor any chance of a test but i hope to be runing a building blog.

[number four]

so it looks like we have a working design

it will be next spring befor any chance of a test but i hope to be runing a building blog.

 

have found this looks spot on?

 

http://www.sparksdirect.co.uk/columbus-pne...vo33ek040hf3bq7