Hello -
I've got a large storage heater on one of the night-time-only tariffs, and it *sometimes* causes the 16A MCD at the consumer unit to trip when it comes on at 11pm. Both the heater and MCD are about 10 years old.
The heater is rated at 3.5 kW at 240V. It is connected via a 13A-fused connection unit, and then directly to the consumer unit where it has its own
16A MCB, which also has a "B" marking.While everything was isolated I checked the resistance between the L, N and E conductors of the cable between consumber unit and FCU with a multimeter, which indicated the resistance was infinite - not the best way to measure insultation resistance I know. I also checked all the cables for damage - they looked fine.
Do storage heaters have a failure mode which causes them to draw a bit too much current when their element is cold? Is the MCB perhaps getting a bit trigger-happy in its old age? Any ideas?
Thanks