RCD FCU price difference

[AndyPRK]

Don't forget that you don't see on the 6 o'clock news every day reports about all the airliners that haven't crashed that day, or about all the people who have not been mugged, raped or murdered. Despite the anecdotes you are hearing about, I would imagine that the great majority of RCD FCUs, of all 'reputable' makes, have been in service for years without any problems.

Kind Regards, John

You say that, but just how common is it for people to have RCD FCU's ?

I think its a small proportion of houses that actually have them.

I'm none to keen on their failure modes. It certainly put me off them.

 

[JohnW2]

No, its expected by the IAM, and the Police that it is the responsibility of the driver to check that his vehicle is roadworthy before every journey. ... Its an offence or two to drive if it is not fit.

Quite, and perfectly reasonable. However, my point is that the frequency with which one is expected/required to check cannot be taken as an indication of how frequently faults are expected to occur.

Kind Regards, John

 

[JohnW2]

Despite the anecdotes you are hearing about, I would imagine that the great majority of RCD FCUs, of all 'reputable' makes, have been in service for years without any problems.

Indeed. But of those, how many have exhibited no problems because they are OK, and how many because there has never an event where they needed to perform? The airbags in my car have never had any problems.

Sure - 'no detected problems' does not necessarily mean 'no problems'. However, my point was obviously the general one that one always has to be cautious about judging a product on the basis of only the negative anecdotes about it.

Kind Regards, John

 

[JohnW2]

...Despite the anecdotes you are hearing about, I would imagine that the great majority of RCD FCUs, of all 'reputable' makes, have been in service for years without any problems.

You say that, but just how common is it for people to have RCD FCU's ? ... I think its a small proportion of houses that actually have them.

I haven't a clue about the actually figures. I don't doubt that it's only a small proportion of houses that have them, but it's still likely to be a large number (quite probably 'millions').

I'm none to keen on their failure modes. It certainly put me off them.

Fair enough - but, again, you're basing that statement on a small number of anecdotes. If it's anecdotes you want, you may recall that a year or so ago, an RCD in my daughter's CU made a terrifying bang, produced clouds of black soot and took out the cutout fuse (not a very pleasant 'failure mode'!) when she pressed it's test button - but I don't think one could use that as an argument against having RCDs in CUs

Kind Regards, John

 

[AndyPRK]

I do recall that RCD John, but I know there must be many CU's out there with RCD fitted and not many reported problems.

The quantity of RCD FCU's I'm less convinced about.

 

[JohnW2]

I do recall that RCD John, but I know there must be many CU's out there with RCD fitted and not many reported problems.

Sure - but my point there (in response to yours) was that the 'failure mode' of RCDs in CUs can also be pretty nasty. As for 'not many reported problems', I guess that depends upon what you count as 'problems' - there is the famous report out there (albeit based on a pretty small sample) indicating that either 1 in 7 or 7% (I can never remember which, without looking it up!) of in-service RCDs are faulty (non-functional).

The quantity of RCD FCU's I'm less convinced about.

As I said, I haven't a clue either. However, they've been available for 30+ years, and if everyone offering them for sale had sold a small handful per year during that period, there would be quite a lot out there. Presumably there will have been a considerable increase in their use since 2008, due to people wanting to add things, compliantly, to installations that did not have central RCD protection.

Kind Regards, John

 

[ban-all-sheds]

However, my point was obviously the general one that one always has to be cautious about judging a product on the basis of only the negative anecdotes about it.

Cue the EU in/out referendum...