Power Shower power.

[Laurence Harvey]

Er’indoors says she fancies changing our bathroom electric shower for a thermostatic power shower. She’s now (after all these years!) decided that our electric shower is a bit lacking;...she’s recently tried our daughters Aqualisa power shower and she’s been ‘converted’.

Can a power shower be run from the attic lighting circuit if it is the type of ‘power shower’ that runs on low voltage via a transformer?

How much power does the ‘power shower’ itself consume?...it can’t be more than a few hundred watts,...can it?

 

[terryplumb]

What provides your hot water ,combi boiler ,or hot water cylinder ,or other ?

 

[cwhaley]

Er’indoors

Sorry its off-topic, but you reminded me of my grandfather who used to say that about my grandmother. Haven't heard that saying in years!

 

[Laurence Harvey]

What provides your hot water ,combi boiler ,or hot water cylinder ,or other ?

Bog standard hot water tank with immersion heater and Condenser CH boiler (not a combi).

 

[terryplumb]

You ought to consider a thermostatic mixer valve and a separate pump, which would give a better performance than a power shower ( they have a small pump built in ). Then 'er indoors will be well impressed !! By the way ,the electric supply to either would need to be RCD protected .

 

[EFLImpudence]

... and a power shower doesn't have to be supplied through a transformer - 240V is allowed.

 

[Laurence Harvey]

You ought to consider a thermostatic mixer valve and a separate pump, which would give a better performance than a power shower ( they have a small pump built in ). Then 'er indoors will be well impressed !! By the way ,the electric supply to either would need to be RCD protected .

Thanks terry;...If it was powered from the attic lighting circuit where would the RCD need to be positioned?

I’ll have a read up on the 'super duper' power shower option,...don’t want to be spoiling her too much though!

 

[terryplumb]

A fused spur from a ring final would very often be the most convenient way to pick up a supply ,and you may already have RCD protection within your consumer unit. Its not usual to connect a pump to a lighting circuit. As your electric shower has a dedicated radial circuit ,and is gonna be redundant ,you could utilise that.

 

[Laurence Harvey]

A fused spur from a ring final would very often be the most convenient way to pick up a supply ,and you may already have RCD protection within your consumer unit. Its not usual to connect a pump to a lighting circuit. As your electric shower has a dedicated radial circuit ,and is gonna be redundant ,you could utilise that.

No RCD,...it’s the old style fused consumer unit,...it will at some point in the next few months be upgraded to new consumer unit, but not quite sure when that will be though.

 

[terryplumb]

Best upgrade the electrics before the shower then.

 

[JohnW2]

No RCD,...it’s the old style fused consumer unit,...it will at some point in the next few months be upgraded to new consumer unit, but not quite sure when that will be though.

Does your current electric shower not have RCD protection (even if separate from your CU)?

Kind Regards, John

 

[Laurence Harvey]

Does your current electric shower not have RCD protection (even if separate from your CU)?

Kind Regards, John

No.

 

[ericmark]

I fitted a power shower, had to removed again when a combi boiler was fitted, actually the non power shower works better, the thermostat in the non power shower it seems is better quality and maintains the temperature better. Maybe we simply did not pay enough for the power shower, however you can't really test the showers you just pay your money and take a chance.

In my case shower is down stairs, and before the power shower was removed, I found the RCD had tripped and no one had noticed, it was less force once the pump stopped we could not wash the ceiling however not sure you really should wash the ceiling with the shower.

The amount of water the shower heads can handle also changes how they work, it seems if the heads are too big it can actually reduce the pressure in some cases. And much depends on pressure of the water to start with, it seems there are a number of hot water storage options, header tanks, or at cold water pressure, and in some cases the heat exchanger in the storage vessel allows instant heating of water as it travels through the store.

Also care is required to ensure the pump can't lower the water in the store to below the immersion heater height or it can burn out the heater.

So step one is test the pressure, do you need a pump, if so how is it best plumbed in, once you know that you will know where the pump needs to be placed, then work out where to get power from. A simple RCD FCU can add the RCD protection, but as to if from lighting or power depends on where pump needs to be located.

 

[Laurence Harvey]

A fused spur from a ring final would very often be the most convenient way to pick up a supply ,and you may already have RCD protection within your consumer unit. Its not usual to connect a pump to a lighting circuit. As your electric shower has a dedicated radial circuit ,and is gonna be redundant ,you could utilise that.

The ‘Aqualisa Aquastream’ range of power showers all use a 12v transformer as far as I can see.

The instruction manual says, quote: “The 230-volt mains supply to the transformer may be taken from the domestic lighting or power ring main via an approved double-pole switched fused spur outlet incorporated in the fixed wiring circuit in accordance with the current wiring rules. The value of the spur fuse must not exceed 3 amps.”

Not sure how valid those instructions are though i.e. ”.... in accordance with the current wiring rules” ??

 

[winston1]

The ‘Aqualisa Aquastream’ range of power showers all use a 12v transformer as far as I can see.

The instruction manual says, quote: “The 230-volt mains supply to the transformer may be taken from the domestic lighting or power ring main via an approved double-pole switched fused spur outlet incorporated in the fixed wiring circuit in accordance with the current wiring rules. The value of the spur fuse must not exceed 3 amps.”

Not sure how valid those instructions are though i.e. ”.... in accordance with the current wiring rules” ??

They are not if they are suggesting a FCU on the lighting circuit, though that is not clear. FCUs are not required or needed on lighting circuits. I doubt if the cable on the transformer is so small it requires a 3 amp fuse (it would not be compliant if it was). The fuse is to protect the cable not the transformer. Any way a 3a fuse has no discrimination against a 6a MCB used for lighting circuits.