Hot Water Tank Setup Advice

[Martin.R]

I need some advice on how our hot water is setup please, I am a total novice when it comes to this area of our house.

I have attached some pictures of our hot water tank and theswitch boxes attached to it.
Could somebody please advise on how this setupworks so I know what to look for if I get any problems.

The reason for this post is this morning we had no hot water but theheating was on, the hot water tank and pipes felt cold.
I turned on the switch on the wall next to the tank and itheated up and we had hot water again.
I am not sure if the wall switch is normally off or on, my daughter had been in the airing cupboard the night before and she has a tendency to switch every switch she finds thinking it is a light


Do we have an immersion heater? It looks like on the tank weeither do or we have the fitting for an element.
It concerns me slightly because if we do have an immersionheater then the boiler must have a fault as we have to have the immersion onfor any hot water (I think).
Certainly when it was switched off we had no hot water.


Regarding the silver box the switch is AUTO or MANUAL(Currently AUTO), I’m sure if some years ago we had an issue and a friend had a look and it was just the switch in the wrong position.

Many thanks in advance for any advice given.

 

[Last Plumber]

The switch is a 13 amp switched fused spur. It shouldn't be on an immersion heater and you have a blank in the top of your cylinder so my guess there is you don't have one.

The switch could be for the heating but that doesn't explain why the heating was working, unless the switch isolates the valve but if it does it isn't wired as I or anyone else might expect.

You need a heating engineer to check it over if it happens again

 

[Best]

Hello and welcome. You don't seem to have an immersion heater, judging by the photos.
It would be a fairly obvious either on the side or top (yours only has a brass plug on top), or in my part of UK an external Willis heater sometimes.
That switch might be for the electrics of heating, or a unused spur for an immersion.
The silver motorised valve is to be left on Auto setting unless it fails or for when system is being drained or filled. It must be working while the heating boiler is heating the cylinder. Although take note that Honeywell motorised valves are nowadays giving trouble

 

[Best]

The switch is a 13 amp switched fused spur. It shouldn't be on an immersion heater ...

Why? They are always used here. The heater is 3kw, so 13amp is fine and an isolator is needed there. They are either a fused or non fused spur in airing cupboards in my area.

 

[Martin.R]

Thanks you for the swift replies.

So as I don't have an immersion heater I had better just leave it switched on?
What is the black switch box for with the 3 setting I II III as it looks on the picture?

Thanks again.

 

[Last Plumber]

Why? They are always used here. The heater is 3kw, so 13amp is fine and an isolator is needed there. They are either a fused or non fused spur in airing cupboards in my area.

Because, if there's voltage drop down to 230 v
You're running at max amperes. That leads to overheating a fuse which will not blow. I've replaced loads that have melted. Should really be 20 Amp double pole switch from dedicated supply 16A MCD or 15 A fuse. People put e, in around here to, if they've spurred off the ring, but it's not something I like doing really. Sparks do it too but it's not 100% safe

 

[Best]

Because, if there's voltage drop down to 230 v
You're running at max amperes. That leads to overheating a fuse which will not blow. I've replaced loads that have melted. Should really be 20 Amp double pole switch from dedicated supply 16A MCD or 15 A fuse. People put e, in around here to, if they've spurred off the ring, but it's not something I like doing really. Sparks do it too but it's not 100% safe

Not sure as I am not a spark, but normally, as you say, they come off a 15amp fuse dedicated supply from consumer unit (or the more modern 16amp MCB). But some are then finally to a fused 13amp spur at airing cupboard. It won't blow until maybe 15amp I believe.
I guess the 13amp fuse is fairly pointless when a 15amp or 16amp MCB is supplying it all

 

[Last Plumber]

Not sure as I am not a spark, but normally, as you say, they come off a 15amp fuse dedicated supply from consumer unit (or the more modern 16amp MCB). But some are then finally to a fused 13amp spur at airing cupboard. It won't blow until maybe 15amp I believe.
I guess the 13amp fuse is fairly pointless when a 15amp or 16amp MCB is supplying it all

Yes. The 13 A fuse is fairly pointless off a radial 15A fused or 16A MCB. You tend to see the 13A fused spur thing more around here when they've spurred off a ring main circuit which is fused at 30A or 32A MCB. In consumer unit. I know they do it to fuse down from 30/32A but it's better wired properly

 

[Last Plumber]

Thanks you for the swift replies.

So as I don't have an immersion heater I had better just leave it switched on?
What is the black switch box for with the 3 setting I II III as it looks on the picture?

Thanks again.

That's your pump and those are speed settings

 

[Dogby]

That is the pump speed selector for the boiler circuit. You haven't shown the programmer in your pics, make sure that is set up to your requirements