On 01/06/2021 11:27, Robin wrote:
On 01/06/2021 09:32, Grumps wrote:
On 29/05/2021 13:21, John Rumm wrote:
On 28/05/2021 17:22, Grumps wrote:
Hi,
I've just had an EICR performed on a property that I let. I wasn't
present during the test and my tenant has reported the following
back to me (I'm too impatient to wait for the full report which
might not be with me until the end of next week).

Apparently 4 16Amp MCBs need to be changed to 6Amp. Each MCB is
connected to just one wall-mounted electric heater. The heaters are
rated from 1500W to 2000W.
The last time I had a look at the wiring (when I decorated some 4
years ago), I'm sure it was 2.5mm2 from the MCB to each heater's FCU.
2.5mm2 and 16A MCBs are a good combination, yes? Even 1.5mm2 should
be good.

Surely if I get the 16A breakers swapped to 6A then that won't be
sufficient for a 2kW heater, and probably not even for the 1500W ones?

What possible reason would the electrician suggest swapping to 6A MCBs?

It seems like you will need to wait for the proper report since
something does not add up here.

I have the full report now.

All circuits have been deemed to be reference method 100.
The 5 heaters are on 1.5mm2 cable with 16A MCB.

Just for clarity, is it 4 MCBs for 5 heaters?

The failures are listed as:
3x 1.5mm cable in a 6A breaker (these are lights and smoke detectors).
Incorrect breaker sizes for heater circuits.

Recommended solution:
Downgrade MCBs to 10A C type for inrush protection of 1.5mm cables.
Split the doubled up 6A circuit.

So my quick questions a
Are you not allowed to have 3 circuits in one breaker?


Assuming the MCB is rated to take 3 x 1.5mm cables (and I can't think
why it wouldn't be) I wonder if the argument is that there is
insufficient resilience (Reg 314's "314.1 Every installation shall be
divided into circuits, as necessary, to: (i) avoid danger and minimize
inconvenience in the event of a fault...").

Which lights are on that MCB and which on separate circuits?


Can you not protect 1.5mm2 ref method 100 wiring with a 16A breaker?







I wonder if that "Method 100" will become a typo for "Method 101" in
response to questions



Well spotted Robin. It has to be method 101!

--
Adam