DIY CH/HW Design - Thoughts? Help?

[Nickfromwales]

4 hours ago, Tin Soldier said:

Disappointed that manifold is maybe not the way as it seemed straightforward for me to do

 

i don’t quite follow what you’ve said nick are you suggesting a couple of well insulated 22m legs headed to a manifold closer to the action?

It's unique so difficult to say exactly how to plumb it. . Do you have detailed house plans showing DHW tank location and bathrooms / kitchen / utility ? If you upload those here I can advise better, apologies if they're already up elsewhere. 

[Tin Soldier]

Hi Nick et Al

 

Attached is a picture of the house extension (and existing house) - I've stripped off some of the text to try and make it easier to read

The old house is on the left with the thick walls. .there is a new bathroom going in though (doesn't currently exist but is drawn)

 

I've documented on there

 

Proposed New boiler location

Proposed Thermal Store Location

Proposed UFH Manifold Location

Proposed HW Manifold Location

 

and location of the existing HW and Radiator Connections (where the existing boiler is)

 

There are new water connections to be run to the following rooms (as per drawing)

 

Shower Room

Ensuite

Family Area Woodburner

Kitchen

Bathroom

 

Cheers

 

Scott

[Tin Soldier]

Also JS

 

I noticed last night the mounting bracket for the existing filter is broken, so perfect excuse to invest in a jumbo

 

Thanks

[Tin Soldier]

I’ve got a local plumber coming round on Tuesday to take a look at the job, any tips on how to assess him/ what I should ask?

 

still not convinced I can’t do it myself but I’ll need help with the boiler/thermal store at the very least

[Jeremy Harris]

What's the worse and best that can happen if you decide the DIY things?

 

Worst case, you end up calling in a plumber to sort things out, and in all probability you will have got much of the hard work done by then, so the job will likely be easier from the plumber's point of view (who will look at stuff like running lots of pipes etc as being the "hard" work, and won't be fazed by the joints etc).

 

Best case is that you will gain a fair bit of knowledge and skill, save a fair bit of money, get the satisfaction of having done the job yourself, gained confidence in tackling other jobs and you have the back up of some people here who've either been up the same learning curve or are already professionals in that trade.

[Nickfromwales]

1 hour ago, JSHarris said:

What's the worse and best that can happen if you decide the DIY things?

 

Worst case, you end up calling in a plumber to sort things out, and in all probability you will have got much of the hard work done by then, so the job will likely be easier from the plumber's point of view (who will look at stuff like running lots of pipes etc as being the "hard" work, and won't be fazed by the joints etc).

 

Best case is that you will gain a fair bit of knowledge and skill, save a fair bit of money, get the satisfaction of having done the job yourself, gained confidence in tackling other jobs and you have the back up of some people here who've either been up the same learning curve or are already professionals in that trade.

+1

Ask the questions here and crack on. Can you solder copper?

[Tin Soldier]

It’s really about design, running myself in circles trying to figure out how to plumb it up... was hoping to speak to a plumber face to face and see what his thoughts were... given long runs etc

[Nickfromwales]

24 minutes ago, Tin Soldier said:

It’s really about design, running myself in circles trying to figure out how to plumb it up... was hoping to speak to a plumber face to face and see what his thoughts were... given long runs etc

It really couldn't be easier to plumb it yourself in Hepworth pushfit pipe.

Whats the worry with the long runs? Talking to a plumber won't make them shorter, and the solution is a simple HR pump and loop. Heating is just two pipes, flow and return, and can be Hepworth too. 

Flow and return from the boiler to the TS and connect hot and cold to it, then order it with whatever space heating tappings you need and connect to those accordingly. 

?  

[Tin Soldier]

JSHarris

A Couple of questions when you get the chance, before I get started.

 

I've looked into 500 litre expansion vessels, and they are too wide to fit through my upper pumphouse doorway, and it would be too difficult to modify to get it in, so I'd be looking to drop down to the 300 litre option. You mentioned you have two 300 litre expansion vessels fitted in parallel. Is this difficult to do, or as easy as it sounds? have you any pics? I've had a look through your blog but not found what I was after.

 

 

Obviously I'm nervous about cutting off water supply to my house whilst I carry out testing, so here's a possibly stupid question.

What is getting the water up from the borehole, all the way up the hill to my house. Is it the flow/pressure created by the borehole pump itself, or the 100 litre expansion vessel, or a combination. The reason I ask is that if I move the 100 litre expansion vessel, or bypass it, I'm not sure if the borehole pump would be powerful enough on its own to get the water up to the migrated expansion vessel.

 

A follow on from this would be to ask whether having an expansion vessel at lower pump house (say the 100 litre existing one) and an expansion vessel/The filters at the upper pumphouse is a valid set up, would it cause any additional problems?

 

Thanks

 

Scott

 

 

 

 

 

 

[Jeremy Harris]

I fitted 300 litre ones for the same reason, a 500 litre one wouldn't fit through the door!

 

Try a single 300 litre, I only used two because my sand filter needs at least 25 litres per minute during backwash every few days, and I couldn't maintain that for the 8 minutes required with just one 300 litre vessel.

 

The are easy enough to plumb in, just a tee fitting on the thread on the bottom, sealed with PTFE tape on the threads, and the inlet and outlet pipe fitted either side.  Pick the right sort of tee fitting for your pipework - for example if using 25mm MDPE then use a tee with the right thread (usually 1" BSPF) to fit the pressure vessel and 25mm MDPE fittings either side.  Use plenty of PTFE tape on the threads on the vessel, a dozen or so wraps will usually do.

 

The pump does all the work, the pressure vessel only stops the pump having to short cycle, nothing more.  In you case there is a significant advantage in having the pressure vessel at the higher pump house, as it significantly reinforces the instant flow at the house.  The pump will happily just run the water up to the upper pump house.  There's no merit in having any other pressure vessel at the lower pump house, it would give no benefit and would just be a nuisance when servicing, as there would be more water to drain down.

 

The filters must, for safety reasons, be fitted after  pump pressure switch, as otherwise a blocked filter could overload the pump.  You could keep the filters at the lower pump house, after the pressure switch, but you might well then get nuisance short cycling as the filters became clogged, so not a great idea.  Better to relocate them to the upper pump house, after the pressure vessel.  Fit shut off valves either side of the filters and a drain cock in the pipe connecting to the filters, so you can just isolate the filters, drain the pressure off via the drain cock and change them without having to drain the whole system down.

[Tin Soldier]

Excellent reply as always, and just what I was needing. thanks very much.

 

I am about to strip out redundant equipment from the upper pumphouse to make way for everything to be shifted and lay a better floor.

 

There would be room for 2x300 litre and I'll make sure the layout allows, but I'm going to try for a single 300 litre and see how I get on.

Whilst I'm at it I'll be installing a jumbo 20" filter

 

I'll be migrating everything as you suggest.

 

just out of interest, if you have a power cut, do you have a backup water supply/ generator to ensure water is still available?

 

 

[Jeremy Harris]

Yoo may well find that a 300 litre vessel is big enough, but a bigger one allows for a larger volume of back up water if there's a power cut.  In our case we have over 300 litres of water stored at around 3 bar or so, enough for a couple of showers plus a few toilet flushes, hand washes etc, so we could manage for a time during a power cut.  Having a small generator to run the pump might be an idea if you tend to get long power cuts, it doesn't need to be massive, something around 2 kW output should be able to handle the pump start up load OK.  If you have the pressure switch fitted with connectors, as mentioned above, it would be pretty easy to just make up a similar lead from a generator to swap over and provide power to the pump system during a long power cut.  You wouldn't need to run the generator all the time, just run it to charge up the pressure vessel then turn it off and don't start it again until the pressure drops at the house.

[Nickfromwales]

If there is already a 100l vessel at the station now and your fitting another larger one nearer the house, I'd definitely keep the second vessel inline as a buffer for service / failure of either / or. If you need to do routine ( annual at least but bi-annual is recommended) inspection and or maintenance, then having a second vessel will allow you to isolate the other and retain a regulated flow. 

Plus it'll give extra volume too. If it's there, and free, why not retain it?

[Nickfromwales]

NB you ALWAYS fit an isolation valve at each vessel, and also you need a drain off between the isolator and the vessel so for the inspection you just shut the isolation, open the drain off, check the back pressure, top up if required, and then just reopen the isolation. 

All told 15-20 mins work max . 

[Jeremy Harris]

1 hour ago, Nickfromwales said:

NB you ALWAYS fit an isolation valve at each vessel, and also you need a drain off between the isolator and the vessel so for the inspection you just shut the isolation, open the drain off, check the back pressure, top up if required, and then just reopen the isolation. 

All told 15-20 mins work max . 

 

Just NEVER fit any valve between the pump and the pressure switch port.  Sometimes people fit the pressure switch to the port on the top of the pressure vessel (the tapping direct into the top of the bladder, not the air precharge Schrader valve),  as often they are either 1/2" BSPF, or 1/4" BSPF, making it a doddle to screw in the pressure switch/gauge directly at eye level, where it's easier to read.  Doing this means that there must be no valve between the pump and the pressure vessel at all, or else there is a risk that someone will shut it, leave the power on, lower the pressure in the pressure vessel and so run the pump dead-headed.  Most pumps will quickly overheat and burn out if dead-headed, unless they are one of the ones with integral protection, like the Grundfos series, with internal motor controllers.

Edited January 4, 2018 by JSHarris

[Tin Soldier]

Thanks Gents

 

I've ordered a jumbo 20 incher along with filters, some granulated carbon (that's whats in the glass fibre tank) and a 300 litre expansion vessel.

 

I can prep the upper pump house and get everything hooked up, prior to actually removing anything from lower.I can plumb everything up as you've both suggested

 

unfortunately the electronic pressure controller you recommended (JSHarris) is no longer in stock so I'm on the hunt for an alternative.

 

the 100 litre expansion vessel may well be used, but I'll be moving it from its lower location to the upper pumphouse... Saves me negotiating through a field full of cows and calfs in the summer months to check on the filters etc. That was the lower pump house will only contain the electrics for the borehole pump and everything else will be up top on the same level as the house.

 

 

[Jeremy Harris]

I have a spare pressure switch if you want it, still in its box.  I bought three of them, wired up two with plugs and sockets so I had one in use and a ready to use spare, but kept the third one unused in its box.

 

Good plan to shift the existing pressure vessel from the lower pump house to the upper one, as it will have a far greater impact on reinforcing the flow rate if it's not driving water up that long pipe.

[Nickfromwales]

2 hours ago, JSHarris said:

I have a spare pressure switch if you want it, still in its box.  I bought three of them, wired up two with plugs and sockets so I had one in use and a ready to use spare, but kept the third one unused in its box.

 

Good plan to shift the existing pressure vessel from the lower pump house to the upper one, as it will have a far greater impact on reinforcing the flow rate if it's not driving water up that long pipe.

What pressure does the pump typically throw out?

[Jeremy Harris]

15 minutes ago, Nickfromwales said:

What pressure does the pump typically throw out?

 

It varies, and depends on the pump and the type. 

 

The cheap positive displacement Polish Ibo pump I have in use at the moment varies from infinite pressure when dead headed (it stalls and burns out at around 25 bar, apparently), whereas a 1 hp nominal multi-stage centrifugal pump like our "proper" one, the Grundfos SQ1-65,  varies from a maximum of around 9 bar at 0 to 4 litres/minute, dropping slowly to about 8.4 bar at 10 litres/min, 6 bar at 20 litres/min and 4 bar at 25 litres/min.  When run at around 1 bar (open pipe at the well head, so just the ~1 bar head in the borehole) I found it delivered a bit over 30 litres/min.

 

As a general rule, a 1hp pump will have a delivery curve around the same as the Grundfos figures above, as long as it's a centrifugal type.  Positive displacement screw pumps, like the Ibo, aren't common, but do have very different characteristics.

 

The true head has to be subtracted from these figures to get the delivery pressure.  In this case there is ~1 bar head loss from the slope of the ground, plus whatever the head loss is from the RWL in the borehole, plus the dynamic head loss from the pipework that varies a lot with flow rate.

Edited January 5, 2018 by JSHarris

[Nickfromwales]

@JSHarris How much was the sq1 ? Just for another job that's chewing through the cheap IBO pump I imported from Poland  

[Nickfromwales]

I'd purposely not mount the pressure switches on the vessels or the vessel pipework for the reasons I mentioned with isolation for service / maintenance / failure etc. There's no reason not to mount it on the peripheral pipework downstream of the pump TBH so don't know why anyone would do that in the first place, other than pure convenience / laziness. 

[Jeremy Harris]

13 minutes ago, Nickfromwales said:

@JSHarris How much was the sq1 ? Just for another job that's chewing through the cheap IBO pump I imported from Poland  

 

Around £600, I think.  It's OK for us, as our borehole RWL is usually only about 5m down from ground level, so the static head loss from the pump to the house is under 1 bar.  Also, I need to restrict the pump flow rate to below about 1 to 15 litres/minute anyway, because of the fine sand problem.

 

11 minutes ago, Nickfromwales said:

I'd purposely not mount the pressure switches on the vessels or the vessel pipework for the reasons I mentioned with isolation for service / maintenance / failure etc. There's no reason not to mount it on the peripheral pipework downstream of the pump TBH so don't know why anyone would do that in the first place, other than pure convenience / laziness. 

 

There are good reasons for putting them on that port.  Firstly, it's what that port is designed for, and it gives an accurate reading of the buffered pressure being fed to the house, not the pressure that is impacted by the dynamic head loss in the pipe.  Secondly, it gets the pressure switch higher up off the ground, making it both easier to adjust and probably keeping it cleaner/warmer (the spring ones have a habit of freezing in winter - can be a real nuisance).  It stays warmer because it's higher up and because the volume of (relatively) warm water in the pressure vessel will tend to stop it freezing,  Finally, it's just a lot easier to read and adjust a meter.switch that's nearer eye level, and a lot easier to just cast an eye over it to make sure it's in the right range any time you go into the water pump room.

 

Our's was originally on the pump pipework, and was a right PITA to even look at, let alone adjust.  It was also constantly wet on the outside from condensation, from being so near the ground, and I doubt that would do a lot for it's long-term reliability.  Right now our pressure switch/gauge is fitted on the top of the tall ozone contact pressure vessel and is easy to adjust and read.  I'd not be persuaded to ever move it back down to an unbuffered position low down, where the pipework comes in.

Edited January 5, 2018 by JSHarris

[Tin Soldier]

Thanks for all the advice

some more questions

 

currently, at the lower pump house the mdpe is 32mm that comes out of the borehole pump, before being throttled down to 22mm polyplumb that is then connected to the (I'm guessing) 1" copper pipe that runs up the field to the upper pump house, it is then restricted again to 1/2" copper under the track to the house..

 

The order of things at the lower pump house are - hopefully you can follow this.

 

lower pumphouse - Borehole pump output (32mm mdpe) > Pressure switch (on pipework) > 100l accumulator tee > 5 micron wound filter non jumbo > Activated carbon filter> 1" copper pipe > upper pump house> 1/2" copper pipe > House

 

I want to keep things as simple as possible- could I leave the pressure switch down at the lower pump house and have the pressure vessel at the upper pumphouse, or do they have to be near one another? the reason I ask is the lower pump house has some lovely wiring already in place, and disconnecting the old and replacing with new pressure switch (supplied by JSHarris) would be a doddle. I would like to continue 32mdpe all the way to the house if possible - is there a reason I cannot, should I use 25mm?

 

The order would then be 

 

lower pumphouse - Borehole pump output (32mm mdpe) > New Pressure switch (on pipework) > upper pumphouse (via new 32mm mdpe) > 300l accumulator tee > 5 micron Jumbo pleated filter> Activated carbon filter> House via 32mm mdpe 

 

any thoughts?

 

as an aside, these pressure vessels are chunky - I hate to take the door off and kick the thing through the doorframe to get it in... 500lite must be huge!

 

 

thanks

 

Scott

 

 

[Nickfromwales]

@Tin Soldier

 

Sizes and dimensions

 

Prices

 

 

[Jeremy Harris]

 

50 minutes ago, Tin Soldier said:

Thanks for all the advice

some more questions

 

currently, at the lower pump house the mdpe is 32mm that comes out of the borehole pump, before being throttled down to 22mm polyplumb that is then connected to the (I'm guessing) 1" copper pipe that runs up the field to the upper pump house, it is then restricted again to 1/2" copper under the track to the house..

 

The order of things at the lower pump house are - hopefully you can follow this.

 

lower pumphouse - Borehole pump output (32mm mdpe) > Pressure switch (on pipework) > 100l accumulator tee > 5 micron wound filter non jumbo > Activated carbon filter> 1" copper pipe > upper pump house> 1/2" copper pipe > House

 

I want to keep things as simple as possible- could I leave the pressure switch down at the lower pump house and have the pressure vessel at the upper pumphouse, or do they have to be near one another? the reason I ask is the lower pump house has some lovely wiring already in place, and disconnecting the old and replacing with new pressure switch (supplied by JSHarris) would be a doddle. I would like to continue 32mdpe all the way to the house if possible - is there a reason I cannot, should I use 25mm?

 

The order would then be 

 

lower pumphouse - Borehole pump output (32mm mdpe) > New Pressure switch (on pipework) > upper pumphouse (via new 32mm mdpe) > 300l accumulator tee > 5 micron Jumbo pleated filter> Activated carbon filter> House via 32mm mdpe 

 

any thoughts?

 

as an aside, these pressure vessels are chunky - I hate to take the door off and kick the thing through the doorframe to get it in... 500lite must be huge!

 

 

thanks

 

Scott

 

 

 

25mm MDPE is probably fine, ours runs on that and when I was testing I had a full 100m roll of pipe connected (didn't wan't to cut it as I wasn't sure what lengths I needed) and our pumps easily flowed in excess of 30 litres/minutes through it.

 

Your final suggestion:

 

Quote

The order would then be 

 

lower pumphouse - Borehole pump output (32mm mdpe) > New Pressure switch (on pipework) > upper pumphouse (via new 32mm mdpe) > 300l accumulator tee > 5 micron Jumbo pleated filter> Activated carbon filter> House via 32mm mdpe 

 

Seems fine, but 25mm MDPE should be OK - with the sort of pressure you'll have 32mm will be overkill, IMHO.  When testing ours I ran the pump through a full coil of 100m of 25mm (didn't want to cut it, as I wasn't sure of the lengths I needed) and the pump was still flowing well over 30 litres/min.

 

It makes sense to leave the pressure switch at the lower end, just remember to set it for 1 bar higher than you want, to compensate for the 10m head loss up the hill.  If you want 2.5 bar to 3.5 bar at the house (a reasonably good pressure) then set the switch to cut in at 3.5 bar and out at 4.5 bar.  It's a good idea to fit a pressure gauge on the port on top of the pressure vessel, just remember to remove the blanking screw in the bottom of the switch/gauge port first.

 

 

Edited January 18, 2018 by JSHarris