Replacement time clock help required.

[r1rider]

Hi all. I have a Worcester 24SBI boiler with an integral analogue time clock fitted to the casing. My question is I would like to fit a programmable digital time clock in the house to avoid trips to the garage where the boiler is sited in order to adjust settings. could someone please tell me which time clock i should purchase? The current unit allows HW or HW and CH options only. thanks guys.

 

[ELZ4742]

you have a gravity system then... most 2ch programers will have the option via a dip switch on the rear of them to chose between that and fully pumped.

 

[PrinceofDarkness]

Almost any twin-channel programmer - capable of being selected for 10-programme gravity HW, will do you. They're all much of a muchness these days.


Lucia.

 

[r1rider]

not really good with plumbing. i know the rads are a sealed system and that i have a big tank in the loft and an immersion in the airing cupboard if that means something to someone ?

 

[ELZ4742]

it means you have a gravity system
as already stated, most 2chanel programers will suffice.

 

[r1rider]

Thanks for the replies. looking at the back of the switch i have a grey cable that i believe brings on the HW and a white cable that brings on the CH ( a manual switch has to be switched on) and the HW needs to be on to achieve this. i think i have a mid position valve in the boiler. my concern is that do the 2 channel timers work in this way or do i have to set the HW time (CH1) to the same as the CH time (CH2) in order for the CH to operate.

 

[r1rider]

what i have is a timer to bring on the HW and a switch which when closed will allow the CH to come on at the same time as the HW if that makes sense? i guess i need a time clock that does the same thing but am not sure if 2 channel time clocks achieve this in the same way ?

 

[onlyfitidealboilers]

Drayton do a good twin channel digital twin channel programmer.

you would have to run a cable tho 5 wires

 

[ELZ4742]

buy a Honeywell ST9400A

 

[PrinceofDarkness]

Yes, a 2-channel external programmer is required for your primitive hybrid gravity system. But it won't allow indepenent timings for HW and CH.

I begin to think that you should seek advice from your local heating engineer.......



Lucia.

 

[r1rider]

if i have a mid position valve surely i should be able to call for CH only HW only or both together. if this is the case then why do the controls on the boiler show HW only or HW and CH??

 

[ELZ4742]

how do you know its a mid position valve and not a HW zone valve?

 

[r1rider]

The valve says mid position

 

[ELZ4742]

your system is a Y plan then. you can have HW and CH timed seperatly on any 2 chanel timer.

 

[ELZ4742]

And to just clarify, your valve has 3 pipe entries, A (ar5es/rads) B(baths/tank) and a third from underneath?