immersion heater off (plug and socket)

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Hi, just wondering if theres an easy way of powering an immersion heater off a mains 3 pin plug. theres no wiring in my house yet except for plugs near mains and would be brilliant if we could get some hot water going.


thanks in advance
 
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am I missing something here? an immersion element is 3kw so running about 12 amps, any reason it cant be run off a 13a plug?
 
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am I missing something here? an immersion element is 3kw so running about 12 amps, any reason it cant be run off a 13a plug?

I did a quick bit of a search on this and...

A British 13 amp electrical socket is designed to work on loads of up to 13 amps. As the voltage is 240 volts, that works out at 3120 watts. (240v x 13a = 3120w). That's the available capacity, so for most practical purposes you can plug in anything so long as the total power of all the appliances plugged in at once isn't more than 3120 watts.

The ring circuit (all plug sockets on one circuit) is normally protected by a 30 amp fuse or 32amp circuit breaker, it can have any number of sockets or fused connection units on it but the maximum load is 7200 watts.

So an immersion heater is a big drain on the circuit and hence it is required it has its own circuit.
 
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On a temporary basis to continue to get hot water, you can use a single length of heat resistant cable to a 13A plug.

Any permanent installation should be from a fixed switched fused spur.

Tony
 
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Should be no problem. No different than plugging in a 3 bar electric fire.

Have done this on numerous occasions for temporary hot water supply when working on heating system. Just make sure to use suitable size/type of flex for the connection.
 
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So an immersion heater is a big drain on the circuit and hence it is required it has its own circuit.
It's a big load, but only for a couple of hours a day.

It's good practice to put each fixed load on a dedicated circuit, but there's no requirement to do so.
 
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I agree.. certainly no harm in doing so, just good practice.
Like ideally putting Fridge Freezers on their own RCBO or outside the RCD ~(as long as the socket is marked up as non RCD protected.)

Other items which should be on their own circuit because of high loading include cookers/hob, electric showers.

Some people even go to the extent of having a separate radial in the kitchen for high load appliances like Washing Machines and Dryers.. to separate them from the existing ring main.
 
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Other items which should be on their own circuit because of high loading include cookers/hob, electric showers.
Different kettle of fish though - these appliances MUST be on their own circuit, as you COULD NOT supply with through a 13 amp accessory.

We're talking appliances that could be fed through a plug and socket - ie below 13 amps.

And i believe it is somewhere in the regs that hot water appliances over 15 litres MUST be on their own circuit. Not just good practise.
 
K

kai

Is it possible to install a 13amp DP switched fuse-connection unit for the immersion? (use 1.5.sq.mm immersion flex to connect the FCU to the immersion).
 
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Is it possible to install a 13amp DP switched fuse-connection unit for the immersion? (use 1.5.sq.mm immersion flex to connect the FCU to the immersion).

since when has immersion flex been 1.5mm ?
 
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