wrote in message
...
Hello and Happy New Year!

Just before the Festive Season we had a power cut and our Honeywell
ST699 central heating timer reset itself. I imagine there is an old
NiCad battery in there which has popped its clogs. I am thinking that
this would be a good time to replace this 24 hour timer with a 7 day
timer.

I would love to hear about peoples' experiences changing their timers.
What timers are good? Did you fit it yourself? Was it a nightmare or
was it quite easy? Is there someone you would recommend we get to come
and do this for us? (We live in Soham - that is between Ely and
Newmarket, East Cambs).

Many thanks,

Ben.

The Honeywell ST699 is just a simple 24 hour timer with one or two on/off
periods a day. I believe it's still available for around £50 if the problem
is not the battery.

Will your system allow you to have the heating on without hot water?

There are better timeclocks around that allow more on/off cycles a day or
different times for different days of the week (eg 5/2 or 7 day). Possible
examples:

Honeywell ST9400C... £51

http://content.honeywell.com/uk/home...ls.htm#ST9400A
"The ST9400C is a 7 day two channel programmer designed for individual
control of both hot water and heating and feature the LoTT display, it also
offers up to three "on" periods per day. Additionally each day may be
programmed differently. This programmer may also be configured as a Mini
Programmer for older gravity - circulation stored hot water systems."

Danfoss FP715Si..... £40

http://danfoss-randall.co.uk/xxTypex...79_SIT313.html

The FP715 Si two-channel full programmer has separate Heating and Hot Water
outputs operating on completely independent time bases for maximum
flexibility. The FP715 Si can be configured by the installer at time of
installation to provide 7 day, 24 hour, or 5 day/2 day operation and to
provide either 2 ON/OFF's or 3 ON/OFF's per day, allowing the time control
to be tailored to match the specific requirement of the consumer.