In article 1096283776.ogrx0+KFEC5L+l2ub2Nj5A@teranews,
"Paul King" writes:
Andrew Gabriel wrote:
In article ,
(Chris) writes:

I have mine under the control of a Comfort alarm system, which
allows me to phone it to switch it on and off, and it will phone
me if it locks-out (not happened yet, except when deliberately
engineered). There are also some timed programs, e.g. for doing
the hot water cylinder for half an hour per day, but as it's
part of the alarm, it has the intelligence not to bother if I'm
away. Also, when the alarm is switched to night mode, the
downstairs zone automatically falls back to a setback temperature
setting.

Some further information on this would be appreciated. Link?

The alarm/home automation system is Comfort, http://www.comfort.org.uk
They have a number of schemes for interfacing to heating systems,
but I'm simply using Comforts outputs to drive relays in place of the
heating controller. The Comfort system is extremely progammable to
do whatever you want, but this flexibility does mean you are going
to need some experience in programming, although it probably doesn't
matter in what (e.g. excel spreadsheet, mail merge, or similar is
probably enough -- you don't need to be a low level assembly language
programmer).

I also have a PC interfacing to the alarm, and this enables me
to switch heating and hot water on and off from work across the
internet.

This too please. Name of manufacturer/software. Link?

The software is written by me, but it's not a product and is somewhat
specific to the house setup it runs in, the Comfort alarm system,
and the type of temperature sensors I use (more so than would be
appropriate for a product). I run it on an old PC under Solaris x86,
but it would easily port to any other unix system.

I've done two installations now. The first one, the PC can switch
the heating and hot water on and off, but system uses the existing
thermostats for controlling call for heat from the boiler. However,
all the timed on/off and most of the manual on/off is handled by the
alarm system. The PC only normally handles remote access across the
internet, and the system continues working fine if the PC should
happen to be switched off.

With the second installation I took this further and the PC actually
handles the temperature monitoring and decides when to call for heat
from the boiler, based on the actual and desired temperature settings.
The desired temperature settings are read from conventional looking
room stats (which aren't really roomstats at all, but potentiometers
from which the PC can read the position). The PC can decide if it is
going to use these pseudo roomstats, or if it is going to use some
other target temperature setting such as frost protection or setback.
This decision can be based on the house occupancy and/or instructions
given to it remotely (across the internet or over the phone). I'm in
the process of enhancing it so the PC can set the boiler temperature,
to make more optimum use of the condensing boiler.

In this second setup, the PC is vital to the operation of the system
(if it died, house could get frozen/burst pipes for example). The
alarm system operates a heartbeat check on the software running in
the PC every hour, and generates an alarm if it stops working (which
will phone out, not the full sirens and lights;-). Similarly, it will
generate an alarm if the boiler reports lockout. Fortunately, this
has never happened to date, but the alarm system can reboot the PC
by power cycling it if it ever needed to, and again that can be
commanded remotely over the phone, or if the PC is still working well
enough, across the internet.

I don't know of an off-the-shelf solution which would do all this,
and if there was one, I probably couldn't afford it. However, this
is a DIY newsgroup;-)

--
Andrew Gabriel