Central heating override
18 April, 2013 - 06:07
Has anyone added a method of triggering their central heating to turn on and off via their HAH?
22 April, 2013 - 20:43
#2
Hi There, Can i ask which
Hi There,
Can i ask which Boiler / Room Thermostat you are using?
CH control is the next thing on my HAH list, as i have a valiant ecotech boiler and weather compensating thermostat i wouldnt want to interupt it doing its thing
What i would like is to either interface the boiler or thermostat on the EBUS (Energy Bus Valiant protocol) and be able to increase / decrease / boost etc
This however means i will need to build an EBUS interface and decode the protocol.
I think the best solution on the forums currently is the Drayton RF Thermostat and Bretts URF examples as linked above
Threre was talk about the possibility of controlling RF Radiator stats similar to these - http://thermalogic.co.uk/
this creates a nice room independant solution
Andrew
20 April, 2013 - 10:47
#3
Terrier iTemp control via RF
>There was talk about the possibility of controlling RF Radiator stats similar to these -http://thermalogic.co.uk/
I did make a start on this, using a Terrier iTemp valve. The people at Terrier don't seem to be interested in providing any details at all. Emails to their 'support' address go unanswered.
From my digging, it seems that it should be possible to gain control over individual valves using a RFM12B at 868MHz. This is confirmed by folks who have used a LightwaveRF WiFi Link unit to control the iTemp valves.
There is a 'training' mode, which allows the pairing of a valve with a given address which is transmitted by the controller.
Not sure if it's possible to set the valve to a specific '%age open' position. However, it does seem to be capable of being told to 'increase/decrease' the set valve temperature.
I'll try to get back onto this before too long.
Derek.
27 April, 2013 - 06:54
#6
its very possible
You could strip apart an RF socket and re-jig the relay to give volt free contacts to override thermostat.
you would need to determine if thermostat has normally open or closed contacts when requesting heating (think they are closed when requesting heating) and a mains supply as well.
will have a look if this is feasible ref the rf sockets monday for you if you want as i have one that is already stripped apart that i was playing with for a different reason.
Dean
27 April, 2013 - 09:16
#7
Absolutely possible ...
... but do take care when working with mains voltages.
Derek.
27 April, 2013 - 09:50
#8
Do not worry Derek
I have made some right "gafs" in my time and wrecked many a cutter by going through mains cables.
Nowdays i use an isolation transformer connected to a variac and rcdX2 on my test bench to minimize injury.
Dean
28 April, 2013 - 08:19
#9
figured out how to get voltage free contacts on HE302
remove the 2 diodes from the point nearest the relay and re-attatch the positive feed.
see rubbish photo here (now taken password protection off this album):-
http://www.packetradio.co.uk/gallery/index.php/HAH
http://www.packetradio.co.uk/gallery/index.php/HAH/DSC_0037
Dean
30 April, 2013 - 20:11
#10
override
That's exactly what I have done. The existing 'call heat' contact is now wired in parallel with an RF controlled relay (stripped down HE303)
It helped to have both HAH and original stat as both of them 'fell over' a couple of times during the cold snap
http://www.homeautomationhub.com/content/boiler-control-using-urf
http://www.homeautomationhub.com/content/outputnode-info
Amoung other threads.
Dean