Yes, I understand where you are coming from, but those are the sizes they are commonly referred to by absolutely everyone in the industry. No one mentions it is the CSA. As I stated, there isn't a 20mm cable.
Instant hot water boiler for shower..??
- Thread starter Bohobee
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Yes, I understand where you are coming from, but those are the sizes they are commonly referred to by absolutely everyone in the industry. No one mentions it is the CSA. As I stated, there isn't a 20mm cable.
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4m2 what is that supplying 10 electric chairs ?
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do you not mean 4mm2
My understanding is that UK domestic T&E cables are referenced by the CrossSectionalArea (CSA) of their L/N cables - therefore cables are quoted as being 1/1.5/2.5/4/6/10/16/25mm2 >
Given the builder has stated that he installed a 20mm cable doesn't really mean anything as far as what has actually been installed and what current it is capable of carrying.
@Bohobee, you need to check with the builder what the 'standard size' of cable was installed, alternatively can you see the cable and see what is marked on it? I presume it has a separate consumer unit and if so what are the ratings of the breakers?
An electric shower is constructed quite specifically to meter it's deliver. Its components (inlet/water tank heater/flow restrictors/outlet hose/shower head etc) are designed as such to precisely meter the water use and electrical current to then meet its documented flow and temp output but still offer an acceptable showering experience (to some)
An instantaneous water heater only really has just one part of what would be in a shower, the heater tank, so generally what flows in flows out and the heater tank can only heat a certain volume by a certain amount, that's dictated by the flow/temp and KW rating. For a mixer shower/tap that usually uses mains water pressure and flow and mixes that at point of use then flow will be low but a water saver/aerator may maximise the 'feel' of that. To have a shower fed by one then the shower will need to be very specifically configured to accept low flow and maximise the available output into a reasonable flow at the shower head. So someone that really knows what they are doing would be needed to get it right
Given the builder has stated that he installed a 20mm cable doesn't really mean anything as far as what has actually been installed and what current it is capable of carrying.
@Bohobee, you need to check with the builder what the 'standard size' of cable was installed, alternatively can you see the cable and see what is marked on it? I presume it has a separate consumer unit and if so what are the ratings of the breakers?
I just don't understand how an electric heater doesn't just basically do the same thing as an electric shower?
An electric shower is constructed quite specifically to meter it's deliver. Its components (inlet/water tank heater/flow restrictors/outlet hose/shower head etc) are designed as such to precisely meter the water use and electrical current to then meet its documented flow and temp output but still offer an acceptable showering experience (to some)
An instantaneous water heater only really has just one part of what would be in a shower, the heater tank, so generally what flows in flows out and the heater tank can only heat a certain volume by a certain amount, that's dictated by the flow/temp and KW rating. For a mixer shower/tap that usually uses mains water pressure and flow and mixes that at point of use then flow will be low but a water saver/aerator may maximise the 'feel' of that. To have a shower fed by one then the shower will need to be very specifically configured to accept low flow and maximise the available output into a reasonable flow at the shower head. So someone that really knows what they are doing would be needed to get it right
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@Johntheo5 The new electric supply has been put in SPECIFICALLY so that I can have an instant hot water heater or electric shower put in and not have to worry about KW sizes. Sorry if I haven't got the terminology right but it is a big fat cable, there is no worry on that side, it must be 25mm then if there is no 20.
@Madrab Thanks for the explanation on the shower vs boiler - makes total sense
Looks like I will end up going with a storage tank then and maybe just put a little under sink instant heater in for one of the sinks so at least there can be instant hot water for when it is used spontaneously
@muggles I didn't say I had a tiny budget! Just I am tring to bring in each element as low as possible! i've had to set my limit at £30,000 and I cannot afford to go over that (financially or mentally!!) but within that i'm also trying to allow a budget for the garden which is currently on a minus figure - every penny I can save on my budget already allocated to items in the building can then go to that... if there was a way of bringing the hot water situation in lower than budgeted then the garden budget grows, however it looks like the heater budget is expanding so something else will have to go! Bye bye fancy pool table probably!
@Madrab Thanks for the explanation on the shower vs boiler - makes total sense
Looks like I will end up going with a storage tank then and maybe just put a little under sink instant heater in for one of the sinks so at least there can be instant hot water for when it is used spontaneously
@muggles I didn't say I had a tiny budget! Just I am tring to bring in each element as low as possible! i've had to set my limit at £30,000 and I cannot afford to go over that (financially or mentally!!) but within that i'm also trying to allow a budget for the garden which is currently on a minus figure - every penny I can save on my budget already allocated to items in the building can then go to that... if there was a way of bringing the hot water situation in lower than budgeted then the garden budget grows, however it looks like the heater budget is expanding so something else will have to go! Bye bye fancy pool table probably!
As suggested, if you can see the big fat cable, see if there is a size marked on it or the fuse box in the house it comes from and see the rating Amps rating on that would help a great deal.
If there is the electrical capacity and finance then I think an 8.5Kw manual shower will do the job, they can be got from £60 (no frills), go looking in screwfix/toolstation, lots of them to choose from. Then you could add a 15L storage heater (3Kw) under sink, that'll give loads of hot water for washing etc and the basin in the bathroom could be run from that too. Of course once the 15L is used then it needs to be left to re-charge but 15L of 60 odd DegC is loads when it's mixed with cold and it re-charges in no time at all. All that could be run off that fat cable.
Again though to be able to advise accurately, it would be good to know what that cable is and what the rating of the fuse box in the house that the cable runs from.
If there is the electrical capacity and finance then I think an 8.5Kw manual shower will do the job, they can be got from £60 (no frills), go looking in screwfix/toolstation, lots of them to choose from. Then you could add a 15L storage heater (3Kw) under sink, that'll give loads of hot water for washing etc and the basin in the bathroom could be run from that too. Of course once the 15L is used then it needs to be left to re-charge but 15L of 60 odd DegC is loads when it's mixed with cold and it re-charges in no time at all. All that could be run off that fat cable.
Again though to be able to advise accurately, it would be good to know what that cable is and what the rating of the fuse box in the house that the cable runs from.
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OK I think i've made a decision finally!! bascically whilst the stored water tank would be the easiest to install and give me the best shower I just don't think it's feasible for the way the building will be used. I wouldn't want to leave it on all the time as it might not be used for days.. so this system would only really work for the occasional guest use. and going with both like I suggested yesterday is by far the most expensive and seems overkill!! so instead I think it has to be an electric shower and small instant heater for sinks. It is the most disruptive as we've not wired for the shower, but I haven't stuck my cladding in place yet so most of the mess can be hidden behind that!
So - my final queston is... can I use the shower riser rail/double head set that I have already bought with an electric shower? Ie lose the thermostatic mixer obviously and instead just swap the shower hose&head that comes with the shower for the one I already have?
(Sorry I don't have the anser to the cable and fuse box etc as I haven't seen the builder since yesterday morning, but as I say I'm sure it's good for what we need and I'm aware it needs to be 10mm cable from the fuse box to the shower)
Thank you all!
finally!! bascically whilst the stored water tank would be the easiest to install and give me the best shower I just don't think it's feasible for the way the building will be used. I wouldn't want to leave it on all the time as it might not be used for days.. so this system would only really work for the occasional guest use. and going with both like I suggested yesterday is by far the most expensive and seems overkill!! so instead I think it has to be an electric shower and small instant heater for sinks. It is the most disruptive as we've not wired for the shower, but I haven't stuck my cladding in place yet so most of the mess can be hidden behind that!So - my final queston is... can I use the shower riser rail/double head set that I have already bought with an electric shower? Ie lose the thermostatic mixer obviously and instead just swap the shower hose&head that comes with the shower for the one I already have?
(Sorry I don't have the anser to the cable and fuse box etc as I haven't seen the builder since yesterday morning, but as I say I'm sure it's good for what we need and I'm aware it needs to be 10mm cable from the fuse box to the shower
)Thank you all!
I have never seen a electric shower that used any thing other than its own hose/spray head but assuming a 9kw shower and assuming a minimum showering temp of 38C from mains at 15C then if your proposed shower can flow 5.61LPM, should be OK.
Wouldn't be the first time I've been asked to fit a separate rain shower and riser kit, but they were on the largest 10.8Kw showers, it worked .... just, it's the overhead rain showers that struggle with low flow.
Electric showers are matched to their heads and hoses to maximise their output but doesn't mean you couldn't try.
Electric showers are matched to their heads and hoses to maximise their output but doesn't mean you couldn't try.
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