Connecting new timer to CH/HW

[thedigger]

Hi, we've recently had a new boiler/unvented cylinder installed to replace the old open vented system in our house. We are having a rewire at the same time, so the boiler and cylinder are currently disconnected from mains and programmer.

My plumber asked me to get hold of a wireless stat, so I got a Celect 908WHB-3-RF/B. He had a look this weekend and said this just controls the central heating (ie, no hot water).

what's the best way to connect the hot water up? As far as I can see, my options are:

• Leave the hot water on permanently. The boiler should only fire when the temperature in the cylinder drops below a certain temperature, but I'm still loathe to leave it on 24/7 while we're on holiday etc
• Get rid of the Celect control and find one which also controls hot water - but my local plumbers merchants seems to think this doesn't exist, plus it would also involve ditching the new controls I bought
• Get a one-channel/one-day timer just for hot water, leave this hard wired in the loft (as this will presumably rarely need to be adjusted)... this is the method the plumbers merchants recommended - can anyone recommend a decent but cheap timer for this?

Cheers!

 

[D_Hailsham]

Can't you take the Celect back and get it exchanged for something else, e.g a Honeywell Sundial RF2 Pack 2?

Get a one-channel/one-day timer just for hot water, leave this hard wired in the loft (as this will presumably rarely need to be adjusted)... this is the method the plumbers merchants recommended

If an exchange is not possible, this is your best option. But get a timer with a one hour Boost button (useful if you run out of hot water), e.g. the Honeywell ST9100A or Drayton LP111 (latest version with Advance/Boost Button).

 

[ChrisOxford]

If return not possible, I'd go for 3rd option too.

I find the cheap Horstmann digital ones from Screwfix very reliable and well made, e.g. http://www.screwfix.com/p/horstmann-c17-timeswitch/27967

 

[thedigger]

Thanks for the replies.

I bought the control ages ago and only tried to get it installed this weekend, so I'm well past the 14 day return period.

Can the Horstmann timer be used to only do HW (ie, can I still run the CH timing through my RF Celect), or do I need to find a 1 channel timer like the Honeywell ST9100S?

Oh, and question I'm fairly sure I know the answer to, but to put the HW boost on, I will need to go into the loft (because there's no chance in hell I'm ripping down my newly plastered walls to run 5-core )

 

[ChrisOxford]

Horstmann C17 is one channel, C27 two channel (and slightly more costly).

For the C17, you would only need 3-core technically: Live, neutral and switched live out. No earth required as it's all plastic (Class II / double insulated). Get the right stuff though, using green/yellow for switched live is asking for trouble.

Could you not run a wire covertly into, say, the airing cupboard or a built-in wardrobe?

 

[thedigger]

Cool, Cheers Chris. I assume my plumber won't have any pitfalls installing different brands of timer on the same boiler?

My house has a very minimalistic look and has literally nothing in it at the moment (the airing cupboard has been removed, and we don't plan on having any built-in wardrobes).

 

[ChrisOxford]

I assume my plumber won't have any pitfalls installing different brands of timer on the same boiler?

Shouldn't be a problem as far as I can tell, assuming he's halfway knowledgable about basic electrical wiring.