We own a small, one bedroom flat (built 1989).
An EICR inspection raised three C2 observations and recommendations:
(A) The shower cable, and mcb were incorrect size (9.5Kw Mira shower) - Recommend replace 6mm cable with 10mm cable (12 meters, surface run, in trunking) and replace 32 amp mcb with a 45 amp mcb.
(B) Sockets were fed via three (2.5mm) cables from a single 32 amp mcb. And, sockets were not in a "ring" - Recommend replace existing 32 amp mcb with a 16 amp mcb.
We agreed to pay £380 to rectify these observations - i.e. Replace the mcb feeding the sockets - And, to replace the shower wiring with 10 mm cable, including the installation of an RCD or an RCBO to protect the shower circuit.
He has replaced the cable, but has not installed the RCD or RCBO which was requested as part of agreed workscope, and £380 charge.
In an exchange of messages he said he didn't fit the 45 Amp (Hager) RCBO as the shower was drawing 46.5 amps, so he had fitted a 50 amp mcb.
My first question to him was:
"Why is my 9.5Kw shower drawing 46.5 amps, on a circuit that should draw a calculated current of 41.3 amps?" he said, he had got it wrong and, yes, it was drawing 41.3 amp.
I then asked where had his first figure had come from, was it measured or calculated. He said (wrongly) calculated.
So - I took a reading with a Clamp meter, set on 60 amp AC range - with shower operating at maximum flow/temperature - and it indicates a steady state current flow of 46.97 amps. The meter was clamped on to the 10mm cable, at the outlet of the 50 amp mcb - utilising a conveniently looped piece of cable that had apparently been already utilised for this function check.
When challenged, he denied ownership of a clamp meter, "they are unreliable", and is adamant that the current is the expected 41.3 amp - and that he will now install a 45 amp RCBO (Hager discontinued their 50 amp version).
I am concerned about "Safety" - life and property. Also on the potential for spurious tripping.
Appreciate comments, please.
An EICR inspection raised three C2 observations and recommendations:
(A) The shower cable, and mcb were incorrect size (9.5Kw Mira shower) - Recommend replace 6mm cable with 10mm cable (12 meters, surface run, in trunking) and replace 32 amp mcb with a 45 amp mcb.
(B) Sockets were fed via three (2.5mm) cables from a single 32 amp mcb. And, sockets were not in a "ring" - Recommend replace existing 32 amp mcb with a 16 amp mcb.
We agreed to pay £380 to rectify these observations - i.e. Replace the mcb feeding the sockets - And, to replace the shower wiring with 10 mm cable, including the installation of an RCD or an RCBO to protect the shower circuit.
He has replaced the cable, but has not installed the RCD or RCBO which was requested as part of agreed workscope, and £380 charge.
In an exchange of messages he said he didn't fit the 45 Amp (Hager) RCBO as the shower was drawing 46.5 amps, so he had fitted a 50 amp mcb.
My first question to him was:
"Why is my 9.5Kw shower drawing 46.5 amps, on a circuit that should draw a calculated current of 41.3 amps?" he said, he had got it wrong and, yes, it was drawing 41.3 amp.
I then asked where had his first figure had come from, was it measured or calculated. He said (wrongly) calculated.
So - I took a reading with a Clamp meter, set on 60 amp AC range - with shower operating at maximum flow/temperature - and it indicates a steady state current flow of 46.97 amps. The meter was clamped on to the 10mm cable, at the outlet of the 50 amp mcb - utilising a conveniently looped piece of cable that had apparently been already utilised for this function check.
When challenged, he denied ownership of a clamp meter, "they are unreliable", and is adamant that the current is the expected 41.3 amp - and that he will now install a 45 amp RCBO (Hager discontinued their 50 amp version).
I am concerned about "Safety" - life and property. Also on the potential for spurious tripping.
Appreciate comments, please.