Implications of replacing Consumer Unit?

[jacko555]

@Roger465 if it's any comfort I have a 1950s ex council house that had been rewired in the 80s and had various dubious looking changes over the years. We had an EICR done and the wiring was deemed to be fine. We made a few changes and had a new consumer unit installed and it was about £400 IIRC.

Similar here. House rewired in the early 2000s

(So 20 ish old)

Electrician did checks. Wiring fine. Upgraded the MCBs to be rcbo's (only the exterior socket had a rcbo)

Used a left over mcb on a redundant radial to power one socket in the pantry to run the fridge/freezers, just in case of nuisance trips.

 

[JohnW2]

Used a left over mcb on a redundant radial to power one socket in the pantry to run the fridge/freezers, just in case of nuisance trips.

Do you mean that the circuit servicing the fridge/freezer does not have RCD protection? If so, do I take it that none of the cables of that circuit are 'buried' (in walls)?

Kind Regards, John

 

[jacko555]

Do you mean that the circuit servicing the fridge/freezer does not have RCD protection? If so, do I take it that none of the cables of that circuit are 'buried' (in walls)

Correct.
The circuit is maybe 10cm in trunking from the CU to the double socket.
We have had a freezer related trip/loss of an upsetting amount of food in previous house.
It seemed like a good idea.

Thoughts?

 

[JohnW2]

Correct. The circuit is maybe 10cm in trunking from the CU to the double socket.

Fair enough - but do you really mean 10cm?

We have had a freezer related trip/loss of an upsetting amount of food in previous house. It seemed like a good idea. Thoughts?

Most people probably would have some buried cable, which rather changes things. A dedicated RCBO is then probably what they would have to consider - although that would then leave the freezer at the mercy of 'nuisance trips' (which seem to be a problem for some people, even though not for me!). A 'non-nuisance' trip of the RCBo is not much of an issue, since it would usually mean that something had gone wrong with the freezer, anyway. The only obvious alternative would be to use something like SWA for the buried cable, or to have the cable in metal conduit (so as to preclude the requirement for RCD protection) but most would probably regard that as too much hassle!

In fact, whilst a house is occupied, it's probably best not to have a freezer on a dedicated circuit - probably better to have it on a circuit whose loss will be more rapidly noticed (the same, in my opinion, with alarms). I have over-temperature alarms on all my freezers (which therefore detect failures of the freezer, per se, as well as lost power) - but, again, they are only of use when the house is occupied. However, at least in my case, even when we don't have a pandemic the proportion of time during which the house is unoccupied for a significant period of time is very small, so we would be very unlucky if a freezer were to fail, or lose power, during our absence - and I'm happy to leave insurance to deal with that very small risk if it ever happens!

Kind Regards, John

 

[jacko555]

Fair enough - but do you really mean 10cm?

Ok, maybe closer to 30cm


I do see you point about using the rcbo downstairs ring would notify us of a trip.

However, the circuit was already there so quick and easy to do.

I've only ever had the one nuisance trip (and none in this house since the rcbo's were added) however it was painful enough to remain bitter about to this day.

Now a fridge temp alarm... hmmm.

 

[JohnW2]

Ok, maybe closer to 30cm ... I do see you point about using the rcbo downstairs ring would notify us of a trip. .... However, the circuit was already there so quick and easy to do. .... I've only ever had the one nuisance trip (and none in this house since the rcbo's were added) however it was painful enough to remain bitter about to this day.

Fair enough (although the photo is not very clear!).

Now a fridge temp alarm... hmmm.

We have a number of freezers. In the 30+ years we've been here, (fortunately!) none has failed or lost power for any significant period of time whilst the house has been occupied. However, on the very few occasions on which one of the temp alarms has been activated (whilst we were here), it has always been due to death/fault of the freezer (without losing power) -something that we may well not have noticed "until it was too late" had we not had the alarms.

Kind Regards, John