wiring up a central heating timer help

[chriz1]

Hi i have a new Central Heating timer that i need a little help with on how to wire it up,
This is what it says on how to wire it

N L 1 2 3 4

Mains Fused HW OFF CH OFF HW ON CH ON

Any ideas?
Thanks

 

[Taylortwocities]

Yes, but first - are you replacing an existing controller?

If so, what make and model is it? What wires are connected where on the old one.

 

[chriz1]

its a Sunvic select XL
and yes it is replacing an old one thats broken
the wires going to the old one were

Plug mains electric L N E

Power to the pump L N E

Another goes down to the boiler L N E

 

[londonboy]

Need more info really.

Sounds like it could be a gravity system.

Off the top of my head:

Neutral = all 3 blues
Live = brown from plug only

1=
2=
3= boiler brown
4= boiler brown + pump brown.

Theres a switch on the back of the timer that needs changing from pumped to gravity.

 

[chriz1]

the heating system is very old say about 40 yrs old
i see that switch,
how do i know if it is a gravity system?
the pump is downstairs near the boiler if that makes a difference
also there is a black wire coming up with the brown and earth wire from the boiler.

 

[londonboy]

Probably 4 big pipes entering/leaving the boiler.

Two will go upstairs (?) to hw cylinder
Two will go towards radiators, and should have pump on one of them.

 

[chriz1]

yes that sounds right,
Any idea where this Black wire connects to then it comes up with the Brown and Earth wire from the Boiler

 

[londonboy]

havent got a clue. what boiler is it?

 

[chriz1]

FUK knows mate?

 

[londonboy]

That flex from the boiler, what colours does it contain?

Brown, black, green/yellow??

 

[chriz1]

it contains Earth Brown and Black

 

[londonboy]

Stick the black in with the neutrals in the timer.

 

[chriz1]

ok will give it a go now and see,at the mo the Pump is ****ed so waiting for a new one to come tomorrow but will see if it all lights up etc now,

 

[londonboy]

Stick the hw on and it should (slowly) heat the tank. Your heating wont work cos of the faulty pump. Are you in the UK?

 

[chriz1]

little confused when you say

1=
2=
3= boiler brown
4= boiler brown + pump brown

theres only 1 boiler brown?