Is it possible to have the Boiler Relay to work only with a single zone calling for heat? I have the main unit set up in an area without any radiators. I want to use the main unit like a general home thermostat. But I don't want all the radiator valve also to call for their own heat demand. Is that possible or is it all or nothing.
Boiler Relay control but only on main zone
Collapse
X
-
As the controller can be used to control temperature in a single zone, this should be possible. That said, if you have no intention of using the ability of Evohome to control up to 12 zones, Evohome may not be your best/cheapest control option.
-
-
I am infact using the evohome to control 12 zones. However some zones are largely unused rooms. I dont want those radiator valve calling for heat simply because the temperature in those rooms dropped below the set point a little.
What i need is for the boiler to fire up only if the main zone has dropped below the set point.
Comment
-
-
Originally posted by HenGus View PostAs the controller can be used to control temperature in a single zone, this should be possible. That said, if you have no intention of using the ability of Evohome to control up to 12 zones, Evohome may not be your best/cheapest control option.
Comment
-
-
Originally posted by bruce_miranda View PostI am infact using the evohome to control 12 zones. However some zones are largely unused rooms. I dont want those radiator valve calling for heat simply because the temperature in those rooms dropped below the set point a little.
What i need is for the boiler to fire up only if the main zone has dropped below the set point.
Comment
-
-
Hi,
If I'm understanding correctly what you're trying to do, it sounds like you want the HR92s outside of the main zone to function more like conventional TRVs i.e. they just open and close to keep the room at the set point when the boiler is switched on by the main zone thermostat, with no control or feedback to the boiler. Is this what you'd like to achieve? If so, then the simplest solution would be to either unbind the HR92s or remove them altogether and revert to using the old TRV heads outside of the main zone. If you want to retain the ability of monitoring the temperature in each zone, but just remove the boiler control feature of the HR92, I'm not sure whether this is possible in the binding setup.
Dan
Comment
-
-
Originally posted by DanD View PostHi,
If you want to retain the ability of monitoring the temperature in each zone, but just remove the boiler control feature of the HR92, I'm not sure whether this is possible in the binding setup.
So no, it can't be done. This is an often asked question because it also makes it impossible to have a zone that is an electric heater - for example you could use a DTS92 as the temperature sensor and a wireless relay configured as a "zone valve" to control an electric heater, which would work except for the fact that as well as turning on the electric element it would call for heat from the boiler via the boiler relay (a zone can't be excluded from turning on the boiler) thus end up running the boiler when no radiators are open, simply circulating hot water through the automatic bypass loop wasting gas.
It would be such a simple feature for Honeywell to add, but they don't seem very inclined to make any major functional changes to the Evohome, only small refinements to existing features.
Comment
-
-
I know I could make something for this. But anything I make would be rely on an internet connection which doesn't appeal.
OK so currently my system uses HRxxs and the Evohome with no boiler relay. I still use my old wired time clock for the scheduling.
I am about to add a single zone underfloor heating and was planning to use the Y87RF2024 thermostat for the UFH so that I could integrate that with my Evohome. Will that mean that I will be moving to full system boiler interlock as a result. Or will the UFH boiler demand be separate from the rest of the system.
Comment
-
-
Originally posted by bruce_miranda View PostOK so currently my system uses HRxxs and the Evohome with no boiler relay. I still use my old wired time clock for the scheduling.
Originally posted by bruce_miranda View PostI am about to add a single zone underfloor heating and was planning to use the Y87RF2024 thermostat for the UFH so that I could integrate that with my Evohome. Will that mean that I will be moving to full system boiler interlock as a result. Or will the UFH boiler demand be separate from the rest of the system.
Comment
-
-
I have a normal S plan system. With a time clock that controls both the hot water and central heating. I then have an Evohome with the TRV controllers. There is no boiler relay connected. I simply use the Evohome to control the TRVs and get feedback on the temperatures in each zone. The boiler is still timed via the old time clock.
Now wet UFH is being added to the radiator system. The UFH is going to be controlled by a Honeywell Y87RF2024 Single-Zone Thermostat. The reason for that choice of thermostat was to register it to the evohome as one zone. But the Y87RF2024 comes with it's own Relay unit. In adding the Y87RF2024 to the Evohome, will all the TRV controllers also demand heat via the Y87RF2024's relay box?
Comment
-
-
I might be going off on a tangent here but why not pair you main zone to a secondary Evohome Controller? Pick up an older one after someone has upgraded and use it, while keeping the other one setup for your other 12 zones. 12 is the limit per controller anyway.
Comment
-
-
That wasnt what I wanted to do. I didn't want all zones calling for heating except the main zone. I knew that if I registered the BDR91 as a System Device boiler interlock then all zones would make the boiler fire if they fell below the set point. What i hadnt appreciated was that I could use the evohome's internal sensor in the main zone and have the bdr91 setup as the accutator for that zone. That way only the main zone would call the boiler if it needed heat.
Just a little too late. I didnt need to buy a Y87RF for my underfloor. I could have just used the evohome controller for that zone paired with its own bdr91.
Anyway hope this helps someone else.
Comment
-
Comment