What size water pump?!?

[Shaun85]

Currently building out a 60ft narrow. Unsure of what pressure pump i should be going for, 25, 30, 40psi!? I will be using mainly Speedfit through out so know that the pipe work and joints can handle higher pressures. Just unsure of what would be considered a good flow from the above ratings. One Shower and Two basins on board. Cheers

[Alan de Enfield]

15 minutes ago, Shaun85 said:

Currently building out a 60ft narrow. Unsure of what pressure pump i should be going for, 25, 30, 40psi!? I will be using mainly Speedfit through out so know that the pipe work and joints can handle higher pressures. Just unsure of what would be considered a good flow from the above ratings. One Shower and Two basins on board. Cheers

 

 

Whichever you choose to go with just ensure that your whole system can cope with that pressure - eg What pressure is the Calorifier PRV rated at ?

 

I have ParMax 3 pumps for both the main water pump and the deck wash pump

 

3.5 GPM

20psi cut in pressure

40psi cut-out pressure

 

Details below.

 

Edit to add - here is a supplier (Same model for same GPM now called the '4')

Link

 

Jabsco PAR-Max 4 Bilge & Shower Pump | Force 4 Chandlery

 

 

Par Max 3 - 4 Water Pump.pdf

Edited January 25, 2021 by Alan de Enfield

[Shaun85]

Nice one Alan I'll have a look!

[Jen-in-Wellies]

Flow rates is as much about pipe diameter, length and number of bends as it is about pressure, perhaps more so. I can actually measure flow rate as I installed a flow meter in the supply to the pump as part of a system to calculate how much water is in the tank. The pump is similar to the one that @Alan de Enfield has shown in the post above. With all taps open in the kitchen and bathroom, the actual flow rate is about half what the pump is capable of, due to the restrictions that the pipework introduce. If you are really worried about flow rate to a shower, then it may be worth using 22mm, rather than 15mm for the runs from the tank and too the calorifier and to the shower, however you will then empty your water tank faster while showering and have to fill up more often! Most people find 15mm pipework with the type of pump shown above perfectly adequate.

Jen

[Alan de Enfield]

1 minute ago, Shaun85 said:

Nice one Alan I'll have a look!

 

 

Just for comparison - I have 2x showers and 2x wash basins and the kitchen sink.

The showers are fed on 15mm plastic 'push-fit' & are more than adequate, not a 'power shower' but as good as the showers at home.

[BEngo]

It is not the pressure from the pump that matters, it is the flow rate. I have a 5 US gallon per minute Johnson.  Many people are happy with 3.5 gpm or even 2.5 gpm as in some Shurflo pumps.   Unless you have a large shower, or need to fill a bath quickly the smaller pumps will work fine. 

 

Fit a separate Square D pressure switch and bypass the one in the pump.  A square D will last longer, is easily adjusted and gives you a better range of pressure.   The 30 to 50 psi cut off pressure version works for me.

 

N

[Shaun85]

Cheers Bengo

[Shaun85]

6 minutes ago, Jen-in-Wellies said:

Flow rates is as much about pipe diameter, length and number of bends as it is about pressure, perhaps more so. I can actually measure flow rate as I installed a flow meter in the supply to the pump as part of a system to calculate how much water is in the tank. The pump is similar to the one that @Alan de Enfield has shown in the post above. With all taps open in the kitchen and bathroom, the actual flow rate is about half what the pump is capable of, due to the restrictions that the pipework introduce. If you are really worried about flow rate to a shower, then it may be worth using 22mm, rather than 15mm for the runs from the tank and too the calorifier and to the shower, however you will then empty your water tank faster while showering and have to fill up more often! Most people find 15mm pipework with the type of pump shown above perfectly adequate.

Jen

Thank you Jen I used 15mm pretty much throughout a house renovation so happy with that flow ( i know house is different to boat etc ) but preservation of water is key, so 15mm it is may alter this once i fit a canal water filtration system. Thank you for the information tho. That Pump seems to be a favoured one with many boaters!

 

[Alan de Enfield]

4 minutes ago, Shaun85 said:

........... it is may alter this once i fit a canal water filtration system.

 

Just interested in what filter system you are planning to use (I've found very few are able to remove hydrocarbons, of which there tends to be quite a lot of in the canals)

[Shaun85]

Been looking at this chaps system

www.waterfreedom.co.uk

I’m a little way off of this installation yet but having travelled the world and drank from some very questionable water sources, guts of ironside here! 

[dmr]

9 minutes ago, BEngo said:

It is not the pressure from the pump that matters, it is the flow rate. I have a 5 US gallon per minute Johnson.  Many people are happy with 3.5 gpm or even 2.5 gpm as in some Shurflo pumps.   Unless you have a large shower, or need to fill a bath quickly the smaller pumps will work fine. 

 

Fit a separate Square D pressure switch and bypass the one in the pump.  A square D will last longer, is easily adjusted and gives you a better range of pressure.   The 30 to 50 psi cut off pressure version works for me.

 

N

 

50psi is 3.5 bar so a bit higher than many boat systems. I think the common PRV's are 3 bar (but not sure) and some calorifiers have quite a low pressure rating, but maybe the OP has a modern stainless steel version.  I have a Parmax 2.9 pump which is adequate for a decent shower and the cutoff pressure is about 25psi. We have very long runs of 15mm and its fine.

 

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

[Alan de Enfield]

10 minutes ago, Shaun85 said:

Been looking at this chaps system

www.waterfreedom.co.uk

I’m a little way off of this installation yet but having travelled the world and drank from some very questionable water sources, guts of ironside here! 

 

 

One of the issues with canal water (and less so River water) is Weil's disease the Leptospira are incredibly small – they can pass through the pores in water filters, even those that claim to remove bacteria. They will pass easily through filters with a pore size of more than 0.2 micron, including membrane and charcoal types.

 

My water filter is 0.1 micron (absolute) and I would not use canal water without the addition of sterilisation tablets (chlorine). It does also need a 'post-filter' activated carbon filter to minimise the taste of oils and diesel.

[Jen-in-Wellies]

3 minutes ago, Alan de Enfield said:

 

 

One of the issues with canal water (and less so River water) is Weil's disease the Leptospira are incredibly small – they can pass through the pores in water filters, even those that claim to remove bacteria. They will pass easily through filters with a pore size of more than 0.2 micron, including membrane and charcoal types.

 

My water filter is 0.1 micron (absolute) and I would not use canal water without the addition of sterilisation tablets (chlorine). It does also need a 'post-filter' activated carbon filter to minimise the taste of oils and diesel.

Weil's disease is not to be messed with. A friend had what he thought was a bad cold, next thing he knew was waking up three days later in intensive care. Was lucky to have survived. It can go very bad. A bit like another disease that has been in the news over the last year. It gets in to the canal water via rat urine, so another yuck reason not to risk it!

Jen

 

[IanD]

Don't get the Weil's reference / water filter comments -- surely we're talking about water from an onboard tank which was filled from a mains tap here, not canal water? Unless the tank is badly rusted or contaminated (in which case, fix the problem!) there's no reason the water quality should be any worse than tap water on land -- remember many houses also used a cold water tank in the roof to supply most of the cold taps, and many still do, this is no worse than a boat tank.

 

[aah, just spotted the OP's "waterfreedom" post, shows what happens when you don't read the entire thread -- well I certainly wouldn't do that...]

 

If the problem is water taste (just like tap water) then feel free to fit a filtration/dechlorination system for drinking water, just like some people do on land. But safety is very unlikely to be an issue with UK tap water, things are different elsewhere including some first world countries like the USA -- especially if you live somewhere like Flint, Michigan...

 

Personally I've drunk "raw" tap water ever since I were a lad in houses and on boats and never had an issue with it, at least in the UK it's probably safer than bottled water ?

Edited January 25, 2021 by IanD

[OldGoat]

5 minutes ago, IanD said:

Don't get the Weil's reference / water filter comments -- surely we're talking about water from an onboard tank which was filled from a mains tap here, not canal water? Unless the tank is badly rusted or contaminated (in which case, fix the problem!) there's no reason the water quality should be any worse than tap water on land -- remember many houses also used a cold water tank in the roof to supply most of the cold taps, and many still do, this is no worse than a boat tank.

 

[aah, just seen the OP's "waterfreedom" post -- well I certainly wouldn't do that...]

 

If the problem is water taste (just like tap water) then feel free to fit a filtration/dechlorination system for drinking water, just like some people do on land. But safety is very unlikely to be an issue with UK tap water, things are different elsewhere including some first world countries like the USA -- especially if you live somewhere like Flint, Michigan...

 

Personally I've drunk "raw" tap water ever since I were a lad in houses and on boats and never had an issue with it, at least in the UK it's probably safer than bottled water ?

When I were a lad we lived in an ancient cottage where the water had to be pumped up from a well. The intake pipe went down and down through the bowels of the Sussex brick clay into the chalk below. Every day my Dad had to pump 100 strokes to fill up the open water tank for the day's use.

You youngsters don't know what yoy're missing....

[IanD]

10 minutes ago, OldGoat said:

When I were a lad we lived in an ancient cottage where the water had to be pumped up from a well. The intake pipe went down and down through the bowels of the Sussex brick clay into the chalk below. Every day my Dad had to pump 100 strokes to fill up the open water tank for the day's use.

You youngsters don't know what yoy're missing....

You 'ad a tank? You were lucky...

 

When I were a lad and we visited my gran in what was then Yugoslavia, she had to send one of the village girls to bring back water from the well at the far end of the village by carrying it on her head in a bucket...

Edited January 25, 2021 by IanD

[Tony Brooks]

What no one has yet seemed to mention is that if the flow rate from the pump is greater than the flow from and open tap/shower, taking account of any pipe restrictions, then the pump WILL cycle. The cycling frequency can be reduced but fitting an accumulator and with an accumulator it may seem that when doing low volume things like filling a kettle the accumulator has stopped the cycling but another time it will not.

 

Theoretically cycling is bad for the pump but practically seems not to be so, but its still a waste of money fitting a higher flow rate pump than that needed.

 

I agree with @BEngo, fit a square D switch, the microswitches in the pumps are far from reliable long term.

 

[OldGoat]

I note that a shower is included in the list of devices.

If it's a domestic thermostatic type blender valve arrangement you may have problems as these are designed to work off mains pressure - hence be careful when you buy it.

At home on a tank fed system a simple bath type mixer works well - after you've juggled with the hot and cold taps....

[Alan de Enfield]

1 minute ago, OldGoat said:

I note that a shower is included in the list of devices.

If it's a domestic thermostatic type blender valve arrangement you may have problems as these are designed to work off mains pressure - hence be careful when you buy it.

At home on a tank fed system a simple bath type mixer works well - after you've juggled with the hot and cold taps....

 

Good advice, but with the ParMax 3 (4) we have no problems with our Mira 'domestic' shower

 

 

 

[OldGoat]

5 minutes ago, IanD said:

When I were a lad and we visited my gran in what was then Yugoslavia, she had to send one of the village girls to bring back water from the well at the far end of the village by carrying it on her head in a bucket...

How time have progressed... Our Cottage had the new fangled electricity stuff in 1946 fed through wobbly overhead power lines (the next door neighbour being a Stockbroker in The City (= loadsa monai)  had a generator and battery set before that pre-war). Mains water didn't arrive until the mid-1950s.

 

Transition to using a boat for holidays was an easy step.  

[IanD]

2 minutes ago, OldGoat said:

How time have progressed... Our Cottage had the new fangled electricity stuff in 1946 fed through wobbly overhead power lines (the next door neighbour being a Stockbroker in The City (= loadsa monai)  had a generator and battery set before that pre-war). Mains water didn't arrive until the mid-1950s.

 

Transition to using a boat for holidays was an easy step.  

The village didn't have any power either -- paraffin lamps for light, wood-fired stoves for cooking...

 

And this was in the late sixties ?

Edited January 25, 2021 by IanD

[BEngo]

Electricity came to MIL in East Prawle (S Devon ) in 1940-41, courtesy of the Chain Home (low) station and associated RAF camp being  built there.  Mains water had arrived previously, to taps by the existing wells, but the supply was enlarged at about the same time as the electric arrived.  Village wide distribution of water, and mains sewage were post war developments, complete by 1953.

N

[Onewheeler]

2 hours ago, OldGoat said:

I note that a shower is included in the list of devices.

If it's a domestic thermostatic type blender valve arrangement you may have problems as these are designed to work off mains pressure - hence be careful when you buy it.

At home on a tank fed system a simple bath type mixer works well - after you've juggled with the hot and cold taps....

 

I'd have thought that most domestic thermostatic shower controllers would be OK on a header tank unless specifically designed only for higher pressure, and even then they'd be good down to 1 bar or so. Worth checking the rating though.

[Ex Brummie]

4 hours ago, OldGoat said:

I note that a shower is included in the list of devices.

If it's a domestic thermostatic type blender valve arrangement you may have problems as these are designed to work off mains pressure - hence be careful when you buy it.

At home on a tank fed system a simple bath type mixer works well - after you've juggled with the hot and cold taps....

A lot of houses/flats I've worked in would be well pleased with a 2 bar/30 psi mains pressure. A pump from a tank of water replicates a mains supply which you would have equally to hot and cold circuits. Thermostatic controls get upset when you have mains cold water, but a gravity tank fed hot supply.

[Shaun85]

6 hours ago, Alan de Enfield said:

 

 

One of the issues with canal water (and less so River water) is Weil's disease the Leptospira are incredibly small – they can pass through the pores in water filters, even those that claim to remove bacteria. They will pass easily through filters with a pore size of more than 0.2 micron, including membrane and charcoal types.

 

My water filter is 0.1 micron (absolute) and I would not use canal water without the addition of sterilisation tablets (chlorine). It does also need a 'post-filter' activated carbon filter to minimise the taste of oils and diesel.

 

6 hours ago, Jen-in-Wellies said:

Weil's disease is not to be messed with. A friend had what he thought was a bad cold, next thing he knew was waking up three days later in intensive care. Was lucky to have survived. It can go very bad. A bit like another disease that has been in the news over the last year. It gets in to the canal water via rat urine, so another yuck reason not to risk it!

Jen

 

 

6 hours ago, IanD said:

Don't get the Weil's reference / water filter comments -- surely we're talking about water from an onboard tank which was filled from a mains tap here, not canal water? Unless the tank is badly rusted or contaminated (in which case, fix the problem!) there's no reason the water quality should be any worse than tap water on land -- remember many houses also used a cold water tank in the roof to supply most of the cold taps, and many still do, this is no worse than a boat tank.

 

[aah, just spotted the OP's "waterfreedom" post, shows what happens when you don't read the entire thread -- well I certainly wouldn't do that...]

 

If the problem is water taste (just like tap water) then feel free to fit a filtration/dechlorination system for drinking water, just like some people do on land. But safety is very unlikely to be an issue with UK tap water, things are different elsewhere including some first world countries like the USA -- especially if you live somewhere like Flint, Michigan...

 

Personally I've drunk "raw" tap water ever since I were a lad in houses and on boats and never had an issue with it, at least in the UK it's probably safer than bottled water ?

 

 

I will mainly be on rivers more than Canals, so will use Canal services from regular tap which Ive no issue with but will use river water through purification. I know about Weils Disease and aware of it, but have consumed river water on my travels around the world through filtration and not had any issues. Im not going to be wreckless through water consumption and will fully ensure water is safe to drink before consuming. So Canal water no - River Water yes - and Tap water no matter where its from always yes. 

RE above all with pump and pressure etc. Thank you for the comments will continue with the set up i was going ahead with as seems to be alright and confirmed via this thread!