Underfloor heating connected to the light switch.

[deadshort]

I mean; when the lights are on and the ufh is on and lights go out due to too much current flowing in the circuit. This would indicate the circuit MCB has passed a current in excess of its designed load. The majority of people would say that was an overload = over load.

Kind Regards,

DS

 

[JohnW2]

I mean; when the lights are on and the ufh is on and lights go out due to too much current flowing in the circuit. This would indicate the circuit MCB has passed a current in excess of its designed load. The majority of people would say that was an overload = over load.

I think everyone would probably say that - since that clearly is an overload. I was just making the point, which you may regard as pedantic, that currents "in excess of the MCB's design load" (which I take to mean it's In) may not result in the operation of the MCB, if the degree and/or duration of that 'overload' is 'modest'.

I personally don't regard it as pedantic, because I don't think it is good design practice (and it's not compliant with regs) to design a circuit whose design current is greater than the "MCB's design load" (In), just because one knows, or thinks it unlikely, that the degree/duration of that excess current will be such that MCB tripping is unlikley. Someone will probably mention diversity - but that's a bit different, since it is a semi-formal way of arriving at a reduced "effective design current", which is then the current which should not exceed the MCB's In.

Kind Regards, John

 

[deadshort]

What is the point of this rambling?

Kind regards,

DS

 

[ericmark]

I see the point of the debate on over loading but until he tells us what MCB is fitted it is all rather pointless.

As stated with no thermostat having the EUH on the same switch as lights could have been done to limit use and so reduce the chance of over heating.

The regulations allow up to 16A for lighting and that would happily do lights and heating in a bathroom. But used for rest of house then there is a likely problem overloading the 5 amp rated ceiling roses and switches.

Swap the BA22d for a E27 and one can simply screw in a 150W inferred bulb. Swap the fitting and you can buy 750 W bathroom heaters clearly designed to run from the lights.

But the big questions have not been answered. We have no idea what size of MCB feeds the bathroom or if it also feeds other items as well.

To try and answer without the information can result in the poster doing something on advice given which is inappropriate simply because what we think is the situation may not be correct.

I think it's a case of waiting until there is a reply there is no point in this rambling.

 

[Josh2k]

Thanks for all your feedback

The ufh does have its own controller.
I am going to get an electrician out to get this sorted as I'm worried some shortcuts have been taken. And as you have probably guessed I have limited knowledge on the subject so won't be attempting anything as it's not the easy fix I was hoping.

Thanks again

 

[deadshort]

Wise and sensible.


Kind regards,
DS

 

[securespark]

And heating should not be on a lighting circuit.

So those combined electric heaters and lights that were sold for bathrooms and quite legally connected, never existed?
Or the 750W infra read electric fires that were fitted

Is not the restriction on a lighting circuit more related to connected load?

I cannot remember how the older heat and light units were wired up.

But the modern ones are intended for connection to a power and a lighting circuit, so as not to place an undue load on the lighting circuit.

 

[JohnW2]

.. the modern ones are intended for connection to a power and a lighting circuit ...

Slight typographical correction required? (a "not", maybe?)

Kind Regards, John