External time clock wiring in General

[SortedPlumbing]

Had an argument with a spark today as i was questioning his wiring - just a quick q -

When wiring an external timeclock from the spur....is it best to run a seperate Live and Neutral to each the boiler and a seperate one to the timeclock??

The way the spark had done it he had ran one cable Live and Neutral through the timeclock then onto the boiler.......

what way is best practice? or does it not make a diff?

 

[JohnD]

....is it best to run a seperate Live and Neutral to each the boiler and a seperate one to the timeclock??

No this would not work since the boiler would be permanently on regardless of the timeclock

The way the spark had done it he had ran one cable Live and Neutral through the timeclock then onto the boiler.......

this way works

 

[SortedPlumbing]

To rephrase that even-

seperate live neutral to each timeclock an boiler with just the switch wire coming from timeclock

 

[JohnD]

if the boiler has the facility for a switched live from timeswitch that would be even better.

 

[SortedPlumbing]

Its voltage free switch connections on the pcb,

 

[WDIK]

reference to the installation wiring diagram will give the answer.

usually if its a volt free contact then a permanent live and neutral to the boiler is required, can be a case that pump run on is a function required by the boiler.

the time switch will require a live and neutral, but the volt free is just that not a switched live from the the clock.

 

[SortedPlumbing]

WDIK - i understand that part but what i dont understand is when you wire it like that should the boiler have a seperate L N from the spur.?

The way he has it the now L N comes from the spur Through the timeclock- with the switch wires.

Does that make a difference to having seperate L N ??

 

[gas4you]

Not wanting to sound awkward, but I do it different to both (I think)

I run the L N E from the switched fuse to a Honeywell wiring block then wire each component from that. Unless it is a combi, then I fit the manufacturers controller usually, built in.

 

[SortedPlumbing]

Think im back to that job next week at some point! just goin to rewire it the way i know how lol -

just had a look at my boilers wiring in my house(been that long since i had case off haha) and when i have wired that i have wired it L N E to the boiler then i have taken my L and N from the boiler to the timeclock obvis with the switch wire.

 

[WDIK]

WDIK - i understand that part but what i dont understand is when you wire it like that should the boiler have a seperate L N from the spur.?

The way he has it the now L N comes from the spur Through the timeclock- with the switch wires.

Does that make a difference to having seperate L N ??

I see what you mean, he may well have used a 5 core to carry the power and a volt free pair.

dave it purely depends on the application mate, if you did have loads of external controls valves stats ect then yes you would need a wiring centre.

generally i dont do domestic dwellings as you know.

I wire a lot of buderus and they them selves have so many choices as to how to control that most of it will go back to the boiler

 

[namsag]

i take it your own about a combi installation or boiler requiring a permenant live .Absolutely nothing up with the way the spark has wired it , no need for both to have a seperate LNE all he is doing is using the LNE of clock back plate as a terminal strip. Think of how potterton ep 2000/1/2 are wired up

 

[twgas]

dont really matter, as long as you have a L N E to timer and boiler (if reqd) and correct switched wire(s).