Re: Real HA - central heating control by the radiator

[ian.bird@xxxxxxxxxxxxxx]

>I have my doubts, for a domestic install anyway, whether full
>proportional on a single rad is worth the
>=A340-50 quid a go extra. For DHW mixing, definitely.
Works for me. I am sure the saved money will be appreciated.

>I'd go with a central control and drop 4 core to the rads. Only one
good
>PSU needed then.
Yep, good plan

>I don't think the rad temperature is worth the effort
My main thought here is not cooling cycles etc. but one simply of detecting
when a valve actuator fails. If the radiator is hot when it shouldn't be or
vica versa then wave the alarm flag. Hopefully this would happen before the
wife starts beating me ;-)

>With a new build I've had the luxury of bringing all the upstairs
>rads(9) back to two manifolds
>and the actuators are on those (Danfoss). JG UFH with 24V actuators
>downstairs.
>They are controlled by an 2 xAP Netiom and DIN relays- not sure I'd go
>to the effort of a PCB.
Nice luxury. I don't have this one to be sure.

I do however have an 8 way relay board already built and tested so part way
there. I even have a serial 8 way xAP enabled switch for said relay board.
All I am short of is the temperature sensing stuff, wiring and associated
mechanical bits and my magic central controller and touch screen slaves.

Hmmm, closer than I thought

Ian




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Lehane Kellett                                       =
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<lehane@xxxxxxx        To:       ukha_d@yahoogroups=
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emon.co.uk>              cc:       (bcc: Ian Bird/CV/=
Novartis)                                                 =
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Sent by:                 Subject:  Re: [ukha_d] Real =
HA - central heating control by the radiator              =
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ukha_d@yahoogroup                                    =
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s.com                                                =
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28/03/2006 17:06                                     =
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Please respond to                                    =
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ukha_d                                               =
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ian.bird@xxxxxxx wrote:
> Hi David
>
> I was thinking about this and I liked Kevin's suggestion of just
switching
> the 10v feed on or off giving me effectively the same as the on off
unit.
> As you say though this opens up potential for future expansion.
>
The 10V units are significantly more expensive than on/off and much more
difficult to get hold of, even
the 24V in the UK seem to be disappearing. Oventrop are one company to try.

I have my doubts, for a domestic install anyway, whether full
proportional on a single rad is worth the
=A340-50 quid a go extra. For DHW mixing, definitely.
> >From my point of view I have to build something that will work by
next
> winter which is not a whole lot of time away taking into account
having
to
> go to work too.
>
> My initial thoughts are:
> 1) Local power supply to power the unit and the valve (no idea how
much
24
> volt supplies are?). May go with POE and a 24volt network so 2 times
Cat5
> to each zone.
>
Excellent 24V 10A supplies are around - check ebay. Siemens, Lambda,
Invensys, etc. All DIN rail
mount for industrial logic controller use.

I'd go with a central control and drop 4 core to the rads. Only one good
PSU needed then.
> 2) Ethernet connected local units to switch the valve. Will also take
a
> minimum of two temperature readings. One would be for the room
temperature
> in the chosen location and the other would be the radiator
temperature.
In
> reality there would probably be the ability to have more room temp
units.
>
I don't think the rad temperature is worth the effort - if you know how
long ago you switched
it off and the current room and outside temperatures that's going to be
enough - unless you
start tracking doors opening and people movement too! Each room will
have a different
cooling/heating slope.
> 3) Mark 1 units would only switch on and off
> 4) Communication protocol is open but I would think xAP would be a
good
> choice. This would also fit in with some graphic displays I am
designing.
> 5) Initially I would probably use HomeVision to control the radiators
(it
> does the heating now) but I would aim to add additional brains in a
home
> made control unit. Ultimately I would not only want radiator by
radiator
> control but also control from every room in the house with
customisable
> abilities. For example the kids rooms would only be able to control
that
> room whereas the main bedroom would not have any limits. I plan
password
> protection on these too so no kids sneaking into mum and dads room for
> dastardly deeds ;-).There would also need to be a master control so
the
> kids don't just set it on all the time. Lots of permutations to
confuse
me
> horribly. Of course it would be nice to record what was on when and
where
> it was activated from which I would include in my home made control
unit.
> This could then be queried from a PC and printed or whatever.
>
> Boiler cycling would be controlled in software somehow. Long way away
from
> that though.
>
> The beauty of this approach is I can phase the system in as time
allows
and
> debug on route. I would also try and make the Ethernet part of the
unit
> separate from the switching part as this will keep costs down when I
change
> the spec. Just have a plug and socket type of connector. Also, since
size
> is not a big issue I can design for 'PCB comfort' rather than for the
> smallest size as I have been doing of late. Roll on that PCB
autorouter
;-)
>
> I would guess 8 units would be my ideal. This would give me one spare
and
> leave one Radiator without a valve so heat can always be dissipated in
the
> case of something going wrong.
>
>
With a new build I've had the luxury of bringing all the upstairs
rads(9) back to two manifolds
and the actuators are on those (Danfoss). JG UFH with 24V actuators
downstairs.
They are controlled by an 2 xAP Netiom and DIN relays- not sure I'd go
to the effort of a PCB.

Lehane

> Ian
>
>
>
>
>
>
>

>                       "David Gumbrell"

>                       <david.gumbrell@g        To:
ukha_d@xxxxxxx

>                       mail.com>                cc:       (bcc: Ian
Bird/CV/Novartis)
>                       Sent by:                 Subject:  Re: [ukha_d]
Real HA - central heating control by the radiator
>                       ukha_d@yahoogroup

>                       s.com

>

>

>                       28/03/2006 01:47

>                       Please respond to

>                       ukha_d

>

>

>
>
>
>
> Hi Kevin,
>
> If you go for a bulk buy, I'd be interested in 6-7 of the proportional
> ones.
>
> Ian: I think proportional will give you much greater scope for decent
> control schemes, although at a cost, obviously. I suspect On/Off is
> going to create more boiler cycling.
>
> Cheers,
>
> Dave
>
> On 3/27/06, Kevin Hawkins <lists@xxxxxxx> wrote:
>
>> ian.bird@xxxxxxx wrote:
>>
>>> Hi Kevin
>>>
>>> Where did you get the price from? Also any idea how much the
other
>>>
> parts
>
>>> needed are? I will need 7 at the end of the day plus maybe a
spare
>>>
> head.
>
>> That was just a Google using the part number - it pulled up a PDF
>>
> pricelist
>
>> Danfoss Gesmbh Presiliste April 2005 Warmetechnik  www.danfoss.at
>>
>>> A 0 to 10 volt control voltage doesn't sound too hard although
for home
>>>
> use
>
>>> I suspect the on/off ones would be just fine.
>>>
>>>
>> I'd prefer the proportional ones I think - at worst case I can
just
>> drive them with ONOFF 10V I guess if that all goes pear shaped.
>>
>> Kevin
>>
>
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>
> Yahoo! Groups Links
>
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>



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