new immersion heater control

Joined
25 Mar 2011
Messages
2,476
Reaction score
326
Location
Devon
Country
United Kingdom
The missing blanks from the normal consumer unit need to be replaced. I guess the space was once filled with the 2 LeGrill MCBs now in the off peak board.
 
Sponsored Links
Joined
25 Mar 2011
Messages
2,476
Reaction score
326
Location
Devon
Country
United Kingdom
How do you know that there are gaps in it?
From the photo.
aaaaa.JPG
 
Joined
27 Aug 2003
Messages
69,782
Reaction score
2,884
Location
London
Country
United Kingdom
Strangely I didn't try clicking the thumbnails in a post where there were two photos, the same, two thumbnails which were also the same, and wrt which the poster wrote "Well I dunno how I got two the same".
 
Sponsored Links
Joined
21 Sep 2016
Messages
46
Reaction score
1
Country
United Kingdom
Okay, I've taken off the front cover and the eight mcb's are all connected up.Quite what the two on the left are connected to, I don't know.
As the unit is all Economy 7 I'll have to wait until after 1am to put my testing screwdriver on the mcbs.
Then, I'll turn off the two on the left, which are labelled B16 (the others are B20) and see if I can track down some devices which are n't working.
 
Joined
27 Aug 2003
Messages
69,782
Reaction score
2,884
Location
London
Country
United Kingdom
As the unit is all Economy 7 I'll have to wait until after 1am to put my testing screwdriver on the mcbs.
All that will tell you, if it works, is that your off-peak supply has started, and I didn't think there was any question about that.

In any event you should stop using that magic wand and get a proper 2-pole tester.


Then, I'll turn off the two on the left, which are labelled B16 (the others are B20) and see if I can track down some devices which are n't working.
If flameport's guess is right they'll be one storage heater and one immersion.
 
Joined
4 Jan 2009
Messages
5,957
Reaction score
598
Location
Herefordshire
Country
United Kingdom
best think to do it put all the MCB down, wait for the night rate to switch over.

Then turn the 2 legrand ones on. Go check out your heaters and see if any are making pinging noises or getting warm.

When your confident 1 or 2 are working, you can flick the others on.

One of them voltage wonds may actually be useful here!
 
Joined
21 Sep 2016
Messages
46
Reaction score
1
Country
United Kingdom
Right, sorry to be late replying.
I carried out AndyPRK' s great suggestion: all the MCBs down beforehand, put up the two legrand ones and checked straight after the change to night rate. Nothing getting warmed up, nothing not working in the house. I put them down, lifted up the others and this morning all the storage rads are beautifully hot.
What I'll have to do is disconnect the cables to the two in question and clamber around the loft to see where the cables are leading - could just be to a disused junction box or something.

Anyway, I now know what to do: connect the lower immersion heater to a spare mcb in my Economy 7 consumer unit for controlled night water heating; and connect the upper heater to its own mcb in the main house consumer unit for daytime boosts. Using a couple of the 20amp switches from Screwfix for airing cupboard control as necessary.

Dunno why I didn't think of this myself, except for the fact that I'm not the sharpest knife in the drawer. You guys on all the diynot forums are bloody marvellous. I can't tell you how much I appreciate you. Many thanks to all.
 
Joined
8 May 2017
Messages
6,741
Reaction score
1,458
Country
United Kingdom
When you switched on the two legrand 16 amp mcbs ,how did you determine whether the lower immersion heater was ,or was not ,connected to either of them ?
 
Joined
4 Jan 2009
Messages
5,957
Reaction score
598
Location
Herefordshire
Country
United Kingdom
I would really recommend the small timer in the first post for the top heater.
You will never forget to turn off that expensive elec then!

However those new tanks do hold heat well, so you may not need to use it. So as a minimum get a 20A switch with neon light, so at least its obvious the top one is on.


Did you old tank have two heaters?
Picture of old tank switches would be interesting
 
Joined
21 Sep 2016
Messages
46
Reaction score
1
Country
United Kingdom
The lower immersion heater is connected to an mcb on the main consumer unit, not to any coming from the Econ 7 unit.
The old copper tank had two immersion heaters with only the lower one still in use. I don't have anything old to photo now.

I've been up in the loft today and have tracked the cable from one of legrand 16B MCB's to an unused storage rad outlet in a wall behind a cupboard. There have been a few changes n the house itself, and a few different makes of storage rads used by somebody, which explains why I didn't know the outlet was there.
When I've stopped itching I'll track down the other 16B to its conclusion. Looks like my problem is is nearing a solution.
 
Joined
28 Apr 2004
Messages
6,152
Reaction score
412
Country
United Kingdom
A lagger once told me showering in tepid water is the best way to decontaminate
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Top