External wiring for Electric Shower

50Twuncle

We are thinking of getting an electric shower fitted in our bathroom - the problem being how to route the wiring back to the consumer unit - which is inside the front door
Is it acceptable to run wiring externally (through the house wall - and round the side of the house, through the wall - to the fuse box) - if so - is there any requirement to use conduit or any special insulated wire (I know that silicon insulation is available ?)
or does it require armoured cable ?
I am not doing it myself - but just want to have my wits about me - when we get people in for quotes !!

Myser

If the cable run will be outside, you should use armoured cable as it is designed to withstand the elements. Bear in mind that if you have a high power shower, the cable size will be very large and difficult to work with if it is armoured.

You should consider alternative internal routes.

50Twuncle

Myser wrote: »

If the cable run will be outside, you should use armoured cable as it is designed to withstand the elements. Bear in mind that if you have a high power shower, the cable size will be very large and difficult to work with if it is armoured.

You should consider alternative internal routes.

It will probably be a 10kW unit...
I take it that a "Power shower" will not be possible - since we don't have a cold water tank, we run everything directly off mains pressure.....
The problem being the design of the house - it is hard to route a cable internally to the meter, a plumber suggested yesterday, that we could route the cable externally, which I hadn't even thought of....

50Twuncle

Are any showers manufacturers better than others ?
Which to avoid - which are best ?
I have read that Mira are quite good
We live in a very hard water area so don't know whether some need servicing more regularly than others..... ?

Myser

Mira is a reputable brand but can be costly. Also have a look at Aqualisa and Creda.

There are some cables that are UV stable and can be used outdoors however, it would still be advisable to run them in conduit with suitable labeling on the conduit.

Is the area where you intend to have the cable running outside frequently used? Is there a chance that the conduit/cable could be damaged?

50Twuncle

Myser wrote: »

Mira is a reputable brand but can be costly. Also have a look at Aqualisa and Creda.

There are some cables that are UV stable and can be used outdoors however, it would still be advisable to run them in conduit with suitable labeling on the conduit.

Is the area where you intend to have the cable running outside frequently used? Is there a chance that the conduit/cable could be damaged?

No - the bathroom is on the first floor at the rear of the house - and the consumer unit is inside the front door porch - so highly unlikely that anything would ever come anywhere near the cable.
Whether the initial cost of the shower unit, itself is £100 or £200 is of no consequence.

50Twuncle

Do electric showers ever get clogged up with limescale ?
I don't mean the head - I mean the actual heating unit itself - the plates or whatever - because we live in a very hard water area....

Myser

Usually scale builds up on the heating element like the older electric kettles with an exposed element.

You can fit a magnet inline with your main water supply to reduce scale build-up:

http://www.sentinel-solutions.net/product/detail/central-heating/physical-devices/scalepro/

http://www.calmagltd.com/calmag-scale-inhibitors

http://www.fernox.com/equipment/scale+reducers

50Twuncle

Myser wrote: »

Usually scale builds up on the heating element like the older electric kettles with an exposed element.

You can fit a magnet inline with your main water supply to reduce scale build-up:

http://www.sentinel-solutions.net/product/detail/central-heating/physical-devices/scalepro/

http://www.calmagltd.com/calmag-scale-inhibitors

http://www.fernox.com/equipment/scale+reducers

I have heard of these scale removers - but have always been dubious as to whether they work - where does the limescale go to - does it build up around the magnet or something ?

Myser

The limescale doesn't go anywhere. Some research a while back by a physicist named Dr. Klaus Kronenberg showed that the properties of the lime molecules within water are altered when passed through a strong magnetic field.

This prevents the lime attaching to surfaces and depositing as scale.

There are some electronic devices which have a coil that you wrap around the pipe. A strong electromagnetic field is generated within the coil and around the pipe.

The magnetic ones are much cheaper however, the magnetic field will slowly degrade over time.

50Twuncle

Myser wrote: »

The limescale doesn't go anywhere. Some research a while back by a physicist named Dr. Klaus Kronenberg showed that the properties of the lime molecules within water are altered when passed through a strong magnetic field.

This prevents the lime attaching to surfaces and depositing as scale.

There are some electronic devices which have a coil that you wrap around the pipe. A strong magnetic field is generated within the coil and around the pipe.

The magnetic ones are much cheaper however, the magnetic field will slowly degrade over time.

But is there any scientific evidence that they work ?
Sorry - but I need proof before I pay good money for things like this..... I am not saying that it doesn't work - but how ?
I have never seen any evidence - it is not related to iron in the limescale either