Adding a pump for bath and ensuite?

GreeBo

Hi all,

I have a recently refurbished bathroom and an ensuite in progress.
We are unhappy with the gravity based pressure in the main bathroom, shower is very weak, sometimes not enough to keep the shower diverted on...

I want to get a pump for the hotpress and lay new piping to the bath/shower mixer and the shower in the ensuite.

I should have access to do this while the ensuite floor is up but I have a couple of questions as to what I should be trying to do.

Its probably unlikey that we will ever have both showers going at the same time, but would like for the system to not collapse if this is the case, would a 2bar pump achieve this? (will we get 1bar each?)

My plan is to lay 3/4" qualpex to the bath and shower, then tee/reduce to 15mm as needed, does this make sense or should I be running 1/2"?

I am also assuming I will need a new cylinder in the hotpress (currently 3 foot), what size do people recommend? I guess the bigger the better but will this have a knock on effect on the water temperature when its being heated by the boiler?

We have two large cold water tanks in the attic, so I believe we have enough capacity here.

Stuart Turner seems to be the recommended brand of pump, any other brands or a recommendation on which size is suitable for my plans? I would like it to be water cooled (or are they all like that now?) so that I can box it in for soundproofing.

Finally, any ideas what a plumber would charge to fit a new cylinder and pump? I will do the electrics and the final connects to bath/en-suite myself once the en-suite is completed.

Cheers to anyone who got this far.
G.

GreeBo

<el bumpo!>

items

Its not a great idea to run a bath of a booster pump, standard 1.5 booster pumps in Ireland cant cope with demand from bath. Some cases pump will not be covered under guarantee if its supplying bath. You'd have to up the pump to a 3.4 to 4 bar pump designed to cope with bath demands.

Your on the tight track piping bath room separate from rest of plumbing, 3/4 to bath then 1/2" to shower and basin, best leave toilet of tank, can be a nightmare when someone flushes toilet at night, pump runs waking people up.

More pressure means more water use so cylinder will have to increase, all depends on how many people in house, and lifestyle, hot water usage is different in every house hold. You might have a standard 36 x 18 cylinder, if demand for hot water is not that high, you could get away with next size up.

When you start looking at showers baths taps etc have a look at flow rates per min, then work out how much hot water you use on average, when you find some figure in ltr's, call into plumbing suppliers to find correct cylinder. Bigger cylinder means more kWs of energy to heat, if your boiler is sized perfect to house with no extra Kw output left over, then you'll have to up boiler size, doesnt happen often as boilers tend to be oversized.

GreeBo

Thanks for the reply.

Im actually just looking to pump the bath/shower mixer and the ensuite shower, not going to do the taps or the toilets in either as they are fine and dont want the midnight noise!

When you say the pump might not cope with the demand for a bath, do you mean the flow rating or something else? Is a 4bar pump not massive overkill? I just want the mixer shower on the bath to be better and have the bath fill quicker, I dont want to drain the tank in seconds with a 4 bar pump though?

Right now it is the 36" cylinder and there are only two of us in the house, also the cylinder is not foam lagged, just has a crappy lagging jacket on it so want to upgrade that anyway, what are you looking at for say a 48" cylinder?

Also, do you need to fit essex flange etc to prevent air reaching the pump or is that overkill?

The boiler is ancient but should have the spare capacity, will check the BTUs on the rads and compare/confirm.

items

1.5 bar cant keep up with the deluge of water that comes out of bath, its too much movement of water through pump impellers, it will work but over time impeller bearing's will wear out, they cant really be replaced as impeller shatters or seizes after bearing wear. To break open pump to replace impellers would prob cost just as much as the pump.

4 bar or 50 bar, its not over kill, it will only pump out water thats available, the only problem you might have is opening up shower valve to much and empty system before finishing shower but not many would be able to have a shower with 4 bar pressure coming out, will take skin off back in shower. A lot of times I find shower valve is just barely open, valves control the pump output / pressure, 4 bar + is maximum output but pump will generally work under 4 bar.

Bath can only fill so much, once bath is not bigger in ltr than combined hot / cold water storage, only problem is it will fill quicker but thats not a problem, more an advantage.

4 bar will more or less be under performing if you get me, doing so, pump will last as its never really under any stress.

In modern homes hot water usage can vary between 35 and 45 litres per person per day, with hot water at between 60 - 65 degrees centigrade.


A wash hand basin tap will use 0.15 litres per second at 40 degrees C

A Kitchen sink will use 0.20 litres per second at 60 degrees C

An average bath can use 60 liters of hot and 40 litres of cold water

Modern showers can use 11 litres of blended water per minute.


Best work out own hot water usage, many a time I've been caught out. People say they only use shower every second day etc. Problem comes with women no offense to any women reading, they tend to stay in shower longer and use hotter water. Last thing anyone wants is not enough hot water or to much hot water so its best take some time to work out actual usage, the above figures should set you up with a good idea.

Forgot to mention, if your upgrading cylinder find a cylinder with a separate hot water outlet for pump use, its the best way to go an remember things are different 5 or ten years down the road, might only be 2 in house now, could be 6 in ten years.

GreeBo

items wrote: »

1.5 bar cant keep up with the deluge of water that comes out of bath, its too much movement of water through pump impellers, it will work but over time impeller bearing's will wear out, they cant really be replaced as impeller shatters or seizes after bearing wear. To break open pump to replace impellers would prob cost just as much as the pump.

4 bar or 50 bar, its not over kill, it will only pump out water thats available, the only problem you might have is opening up shower valve to much and empty system before finishing shower but not many would be able to have a shower with 4 bar pressure coming out, will take skin off back in shower. A lot of times I find shower valve is just barely open, valves control the pump output / pressure, 4 bar + is maximum output but pump will generally work under 4 bar.

Ok I think I get you. You are saying get a bigger pump and let the mixers/valves control the actual pressure the users feels?

items wrote: »

Bath can only fill so much, once bath is not bigger in ltr than combined hot / cold water storage, only problem is it will fill quicker but thats not a problem, more an advantage.

4 bar will more or less be under performing if you get me, doing so, pump will last as its never really under any stress.

Will there be a problem with the pump cycling though? My parents have a pump and unless you turn the taps on near full the pump will cycle on and off as if its not getting enough flow to keep it on?

items wrote: »

In modern homes hot water usage can vary between 35 and 45 litres per person per day, with hot water at between 60 - 65 degrees centigrade.


A wash hand basin tap will use 0.15 litres per second at 40 degrees C

A Kitchen sink will use 0.20 litres per second at 60 degrees C

An average bath can use 60 liters of hot and 40 litres of cold water

Modern showers can use 11 litres of blended water per minute.


Best work out own hot water usage, many a time I've been caught out. People say they only use shower every second day etc. Problem comes with women no offense to any women reading, they tend to stay in shower longer and use hotter water. Last thing anyone wants is not enough hot water or to much hot water so its best take some time to work out actual usage, the above figures should set you up with a good idea.

Thanks for the guide!

items wrote: »

Forgot to mention, if your upgrading cylinder find a cylinder with a separate hot water outlet for pump use, its the best way to go an remember things are different 5 or ten years down the road, might only be 2 in house now, could be 6 in ten years.

Thats something else I wanted to ask about. Looking around I can see lots of different types of cylinders, I know I want a lagged one, but what does "pre-plumbed" mean? Can you recommend any types of cylinder? I reckon I will go with 46".

Foleyart

We built a new house a few years ago and having had experience of a crappy electric shower in the last house decided on a different system. Put in a cold water tank in the shed with the wood pellet burner. 300 litres with a variable speed pump. This means that all the water coming in to the house bar the kitchen sink mains tap, is under pressure. Two showers and full pressure all the time. 300 ltr. lagged hot water tank in the house. Not a solution to your dilemma but an alternative none the less.

items

GreeBo wrote: »

Ok I think I get you. You are saying get a bigger pump and let the mixers/valves control the actual pressure the users feels?


Will there be a problem with the pump cycling though? My parents have a pump and unless you turn the taps on near full the pump will cycle on and off as if its not getting enough flow to keep it on?
Thanks for the guide!



Thats something else I wanted to ask about. Looking around I can see lots of different types of cylinders, I know I want a lagged one, but what does "pre-plumbed" mean? Can you recommend any types of cylinder? I reckon I will go with 46".

That's right, user valves control pump output. Not sure what pump is in your folks but most I know of, brass or stainless body pumps they run as soon as pressure is lost enough to activate flow switch. If pressure is backing up due to tap not open enough the pump might turn off, then come on but its not really a problem, once pump has a constant supply of water, it can come on and off all day long without creating problems.

Not sure about pre plumbed, combi cylinders are pre plumbed, cold water storage ontop, hot water storage underneath, maybe you confusing combi with standard.

Not real recommendation of copper cylinder, they are pretty much all the same, they all meet plumbing standards / requirements without them, cylinder would not be allowed sale in market, pre insulated copper cylinder matched to size you need along with a separate hot water outlet for bath/shower pump is way to go.

You could do as mentioned above, fit a un vented cylinder, normally stainless steel. These are by far the best for heat recovery and time spent holding onto heat. For this cylinder to work you would have to pressurize entire system by using a Grundfos MQ 30 single impeller pump. These type of systems are not ideal for 2 story house with hotpress, Grundfos pump can be noisy with vibrations, wooden floor etc. It;s a big job to pressurize a gravity system. If you had a garage you could fit everything there, storage water, pump, cylinder etc then pipe it all into house but lots involved.

cnocbui

A 3 bar pump would be fine for your usage I believe. I have a 3 bar Stuart Turner and it is set up so as to provide full pressure to the whole house - 4 bedrooms and four occupants. It is located in the hotpress and I haven't bothered boxing it as the noise is not really objectionable enough to warrant it. Late night toilet flushes result in far more noise from the toilet itself than the pump. With 3 bar, the cistern refills very rapidly.

There have been no issues whatsoever related to filling a bath or cycling.

I took twin 3/4" pipework from the hotpress to our ensuite through the attic space as the Hansgrohe fittings were 3/4" anyway.

I didn't change the hot cylinder, which is roughly 130L in volume, and it suffices with a programmable timer and not trying to have two showers simultaneously or a shower immediately following a bath being run. We have coped very well with guests and 8 people in the house by a bit of scheduling.

Don't underestimate the benefits of pressurising the whole house, rather than just a shower and bath. Filling a kitchen sink in under a minute, instead of going a away and reading a chapter of a book, every day of every year, is not an inconsiderable time saving. Wasting large amounts of time waiting for water to flow is a bit silly if you have a pump available that can shift it at 50L a minute.

items

That's the one to go for ST 3 bar. A lot of people make the mistake by fitting a 1.5 shower pump to boost entire bathroom. The both look similar sometimes its easy to make the mistake.

GreeBo

FYI Ordered a StuartTurner 3bar Twin Standard from the UK, delivered to my door for €330.
Arrived yesterday.

Looking for a boiler now. I dont think I need a SS one and they seem more expensive. Thinking about a 50" 150l tank.

Any recommendations on where is cheap in Dub for them?

items

Good choice on pump, ST and Grundfos are the only two pump's I'd recommend.

You say boiler, you prob mean cylinder and SS for stainless, stainless cylinders tend to be pressurized where a single impeller pump boost's entire plumbing system.

Copper cylinder is what your after, I found Heatmerchants for best deal they are more a plumbing / electrical / tile / floor franchise so prices can be keen. I worked off an account but even so they tend to have good prices, best ring around all local plumbing suppliers.

Dublin suppliers, Heatmerchants, DPL, Davey's or Davis, Heating Distributors, HEVC, Chadwicks, those few come to mind. You could also ring Coppercraft cylinder makers direct, might find some savings there, from what I remember they are located in Dub.

Tank stores cold water, cylinder stores hot water, sinks for washing dishes, basins for brushing teeth.

GreeBo

Yep that should have read cylinder rather than boiler

I gave heatmerchants a bell and ther are looking for €423 for a 60x18 but I found one here for much less (€287)
Anyone ever use them?

Also, I'm looking at the current cylinder setup and just noticed that there is pipework joining the two connections for the coil with a valve on it, so the flow and return are connected outside of the cylinder.
Is this normal? I've never seen it before and cant imagine what its for? I'd guess its not helping my boiler much as the flow temp will match the return a lot of the time...?

The valve was wide open and I have since shut it (not fully)

Any ideas?


Finally, I read on here that you shouldnt use QPL for connections to the cylinder as they will flop around when hot, is this true? I would assume they can/will be fixed to the wall etc if needed?

Cheers!

items

Sorry about the delay. You seem sorted with cylinder, thats a good price.

The link between cylinder flow and return is a heating bypass and must be kept that way. You prob have some form of control over heating / hot water, a by pass is needed in cases where all heating controls are satisfied (thermostats) while boiler remains powered on (time clock). The by pass allows boiler to circulate should all motorized valves / thermostatic close, it should only be cracked open a slight bit, no real efficiency issues with a by pass as its only circulation, burner wont be long shutting down as temp will soon be reached if only circulating through by pass.

Pex shouldn't be used in exposed areas, its not ideal as it cant withstand any abuse from dragging things in and out of hotpress. Pex cant be used within 1 mtr of a heat source, your hot press could be well over a 1 mtr away but that means little when heating is on for just cylinder as pipe work is pretty much under max temp the entire distance from boiler to cylinder. Best advice not to use pex in hot press for heating, pex can be used for plumbing except for cylinder vent, its against regulation to use pex for cylinder vent as its not rated to carry water from an over heated cylinder.

GreeBo

items wrote: »

Sorry about the delay. You seem sorted with cylinder, thats a good price.

No worries, just dont let it happen again

items wrote: »

The link between cylinder flow and return is a heating bypass and must be kept that way. You prob have some form of control over heating / hot water, a by pass is needed in cases where all heating controls are satisfied (thermostats) while boiler remains powered on (time clock). The by pass allows boiler to circulate should all motorized valves / thermostatic close, it should only be cracked open a slight bit, no real efficiency issues with a by pass as its only circulation, burner wont be long shutting down as temp will soon be reached if only circulating through by pass.

Ah I didnt think of a bypass. I have installed TRV's on all rad's except the bathroom and ensuite (for this very reason).
I still think it must cause an issue with the boiler though, even when there is a need for hot water surely this bypass is allowing hot water flow straight back to the boiler making the boiler think it can shutdown? (I have the same issue with the flow and return pipes from the boiler that are touching off each other within the same oversized pipe insulation :rolleyes:

items wrote: »

Pex shouldn't be used in exposed areas, its not ideal as it cant withstand any abuse from dragging things in and out of hotpress. Pex cant be used within 1 mtr of a heat source, your hot press could be well over a 1 mtr away but that means little when heating is on for just cylinder as pipe work is pretty much under max temp the entire distance from boiler to cylinder. Best advice not to use pex in hot press for heating, pex can be used for plumbing except for cylinder vent, its against regulation to use pex for cylinder vent as its not rated to carry water from an over heated cylinder.

I have the pex all routed now, under the main bath and on through into the ensuite and back up into the hot press, all 22mm and capped off.
My "plan" is to box them off inside the hotpress so they are not loose and also cannot be hit off.
I guess the easiest thing to do would be to feed the pump with copper and then use the pex on the outlet? This would be over the required 1m and the flexi hoses on the pump should makes for easy connections?

Finally, what sort of run can you do with pex before it needs to be supported? Right now I have a 4m stretch that is essentially sitting on the ceiling below in the middle, I cant get access to clip it up in the middle, just at both ends. I was thinking that I can push down some 50mm foam insulation that I have and this should stop it rattling off the ceiling and also support it?

Cheers for all your help!

items

Using one rad to act as an open circuit is pretty much same as the by pass you have fitted, it might have to stay if your hot water circuit is separate from heating and under control, could be a case where you've only cylinder circuit on for summer and cylinder control could close of circulation while boiler remained on, only you would know. Best leave by pass fitted, water follows easy paths, little to no water is circulating through by pass if valve is restricting flow, pipe in between might feel hot but thats only transfer of heat. The only time real circulation takes place through by pass is when their is no other circulation through rads / cylinder.

Using pex for 1st fix plumbing from hotpress to bathroom is fine, not sure what levels you've brought 1st plumbing into hotpress? If possible try to have pipe work higher than pump. You don't want to limit your flow from pump, best to come straight out of pump with little to no bends etc. This will help when connecting to flexi hoses, best not bend them as they can kink over time, reason for flexi is to reduce sound, not to bend all over the place. Its far handy to use copper for hotpress work than spend time boxing over pex if you get me.

It would'nt take much more than a length of 3/4 to connect up pump from existing pipe work to 1st fix pex. You might have to use more fittings, if possible rent out a benders for a day while doing job, pipes can be bend so no need to use many fittings. Dont forget to install isolation valves, 4 in total and fit them to end of flexi, pump wont be covered under warranty without isolation valves.

Fix pex where ever you can, rigid pipe recommended fixing is 1300 vertical, 1500 horizontal, no real recommended distance with pex that I know of. Fix pex soon as it starts dipping or going off line, dips in pex creates air locks but you wont have that problem as its pressurized. Flexi hoses will take the knock out of most loose pipework so don't be to concerned with knocking pipes after pump, I've never noticed any problems by just fixing pipes where ever I could.