Immersion Timer wiring question

Cmar-Ireland

Hi folks,

I'm fitting an immersion timer in the hotpress. So far I've run the supply into a 20A switch, and from there to the timer.

I want the timer to switch on the bath coil to heat the water so we can have a full tank.

My question is, what wire from the immersion should go to the timer?
The brown wire is connected to the thermostat. Black wire is connected to T.

Thanks.


20A switch




Greenbrook T23H




Dual coil immersion

meercat

important to check that the timer is rated above 15amp
you need to feed the timer first( from the fuseboard)
then a cable from timer to the switch( marked to appliance)
(you need one of these)
http://www.meteorelectrical.com/switches-and-sockets_white-range_1-gang-2-x-20amp-switch-dual-immersion-switch.html
then connect(as per your picture)
blue sink
black bath
brown neutral
green yellow earth
note this is an old configuration that suits your element only

the new regulations also forbid switches and timers inside the hotpress
turn power off when working on this

Cmar-Ireland

Hi Meercat,

It was wired up as per your post, but the other day I noticed the water wasn't heating up. So I checked the dual immersion switch and some of the contacts inside were scorched and partially melted.

Should the switch not be before the timer?


Also, I've just noticed that the timer says "13 (2) A 250v"
So it doesn't seem suitable for the job?

meercat

timer first for sure

your timer is rated 13amp so it will do your immersion
if you can post a pic of the top of immersion including thermostat

Bruthal

Yes timer first, otherwise you will be cutting the power supply to the timer when you switch off the immersion switch.

Bruthal

meercat wrote: »

if you can post a pic of the top of immersion including thermostat

Yes thats whats needed, a clear close up picture similar to what the OP has already, except showing the entire top of the immersion. Probably need a proper dual immersion switch again too.

Cmar-Ireland

The way it was set up was that the immersion switch was always switched on (to bath) and the timer controlled the supply to the switch. Could this be why the switch burnt out?

Bruthal

The immersion switch would burn out possibly because the switch is a cheap one, or the connections of wires into it were not tight enough, the timer being before it would have nothing to do with it burning out.

That immersion has the brown in the flex as neutral, black probably bath, blue sink and earth wire is earth.

A single switch like is on it now could be used to just switch the bath element on and off, but the blue flex at the switch end should be put into a connector, as this will go live as the single stat opens when the cylinder is up to temperature and the stat opens.

The proper immersion switch would be recommended though.

The timer should be before the switch as already said in the thread, fitted with immersion MCB off and confirmed as off with a test of the voltage at the switch before and after its switched off.

Cmar-Ireland

Cheers for the replies.


Here's a pic of the burnt switch. It's a Power Master, don't know if it's a cheapie one.




So are the correct colour wires in the right positions on my immersion?

If I get a new dual switch, it will have earth, neutral and two live outputs.
N=Blue
E=earth
Sink Live = ?
Bath Live = ?

And the immersion?

E=earth
T= ?
N1= ?
Stat= ?

I'd like to have the wire colours correct as per standard.

Cheers

meercat

Leave cables untouched in your immersion and connect into switch as per my post #2

Cmar-Ireland

Any particular brand of switch I should get?

Diggerdunne

MK and Crabtree are good brands....

Cmar-Ireland

Right, I got a new switch, but it has different connections than the old one.
I can see where the L, N, E, supply are connected. But where do I connect the output to the immersion?



Thanks

Bruthal

Flex connects as follows, according to how its connected to the immersion in your photo.


Brown to Nout
Black into L1
Blue L2

And Lout must be connected to COM with a short piece of wire.


When the immersion is connected, look at the ESB meter when its switched on to sink. The less stuff you have on the easier as the meter will be slow for this test.

While you watch the meter, have someone switch it to bath, and the meter should speed up. If it slows, turn off the immersion MCB again and swap black with blue in the switch and re check using ESB meter again.

Cmar-Ireland

Thanks for the help folks, will wire it up and let ye know how it goes.

Cmar-Ireland

Wired it up and all seems to be okay. I have to swap the bath and sink wires as I didn't get a full tank of hot water today. Timer was set for 1 hour, so should have been enough to heat the tank......I think?

Bruthal

Cmar-Ireland wrote: »

Wired it up and all seems to be okay. I have to swap the bath and sink wires as I didn't get a full tank of hot water today. Timer was set for 1 hour, so should have been enough to heat the tank......I think?

Yes just swap blue with black and see if that gives you the full tank. An hour should be enough alright. Or get someone to swith from bath to sink and back a few times while you watch the meter. As they switch from sink to bath the meter should speed up.