Re: Re: Control central heating via PC, ideas please?

[Kevin Hawkins <yahoogroupskh@xxxxxxxxxxxxxx>]

A 35% price incease certainly focusses your mind - home energy cost is
now a very worrying issue (aside from the green ethics).

I believe another good technique - if you have a modulating boiler is to
try and reduce the water flow temperature down such that the provision
better balances the demand.  ie your radiators run cooler but just keep
the room warm.  This avoids boiler cycling and also the cycles /
hysteresis that a switching room stat can introduce.  It's much harder
to manage over multiple rooms though and benefits from an analogue
rather than on/off demand signal (how much heat is required). It's
something I'm experimenting with too as well as proportional valves.

Some people have mentioned that running a modulating boiler at low
demand is not as efficient (they operate most efficiently when fully
loaded) but of course you would then have lots of on/off cycling, and
rads that change a lot in temp.   I believe some fancy systems have
mixing loops within zones allowing the return flow to mix back with the
heat provision effectively creating different flow temperatures in each
zone which seems ideal.

K

Gary wrote:
> Thanks Simon, I enjoyed reading your article, although as i say I'm
> not brilliant at software. But i did understand the concepts.
>
> I hope this subject will create a lot of discussion and perhaps a
> project for some of us on here?
>
>
> regards
>
> Gary
>
>
> --- In ukha_d@xxxxxxx, "Simon McCaughey"
<simonmcc@...> wrote:
>
>> Gary,
>>
>> I don't know how much help this will actually be to you, but I
>>
> changed our
>
>> 3-zone central heating control to computer controlled about 2
years
>>
> ago, and
>
>> have never looked back. I wrote my own software client so the
>>
> laptop, and
>
>> kitchen pc could both control the heat, and i also have a remote
web
>> interface, and a sms interface (its great to text the heating 20
minutes
>> before you arrive home on a cold winters evening)
>>
>> This is an article I wrote at the time
>> http://docs.google.com/Doc?id=dd8r2tb7_2gv37f6&hl=en_GB
>>
>> I used a serial controlled VIOM connected to some bigger relays
which
>> control the motorised valves. There are hard buttons in the
utility room
>> too.
>>
>> The basic premise of my system is that a little human intervention
>>
> is better
>
>> than a "smart" thermostat. I think it has saved us a
fortune in
>>
> heating oil.
>
>> Simon
>>
>> On 30/07/2008, Gary <questuk1@...> wrote:
>>
>>> Hi,
>>>
>>> With the just announced price rise in gas prices, I think it's
time to
>>> see if i can save money by controlling my boiler using a lower
Power
>>> PC such as a mini ITX. Then I can have lots of different time
zones
>>> and more accurate control of the temperature at giving points
in
>>>
> the day.
>
>>> For example, I have a RF wall mounted thermostat, but you can
only
>>> adjust this in 1° intervals, and sometimes that can make
it too hot in
>>> a room, wasting gas.
>>>
>>> I'm not sure how to interface and control the boiler yet may
be
>>> Ethernet if there is such a way?  or perhaps using RF control?
>>>
>>> As I work electronics that side isn't too hard its more the
software I
>>> will have trouble with?
>>>
>>> Has anyone attempted this on the group?
>>>
>>> I'm sure many of us now have a requirement for such control,
so any
>>> comments welcome and also any ideas.
>>>
>>> Regards Gary
>>>
>>>
>>>
>>>
>>> ------------------------------------
>>>
>>> **** Sponsored By http://www.Berble.com ****
>>> ****       Computers You Carry          ****
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>> --
>> Regards
>>
>> Simon
>>
>>
>> [Non-text portions of this message have been removed]
>>
>>
>
>
>
> ------------------------------------
>
> **** Sponsored By http://www.Berble.com ****
> ****       Computers You Carry          ****
>
>
>
>
>
>
>


------------------------------------