Multi zone central heating

m3y

All, some advice needed, just moved into a house which has a combo boiler (recently installed) which is running 9 radiators. Now my wife doesn't work and we have 2 young kids so someone is home most of the time, in the day mostly only a couple of rooms are used so I want to look in to having a zonal system installed to save on heating costs .
Can someone recommend any not too expensive options. I want ideally something like hive but not sure how their multi zone system works? Would I need to reinstall the heating system into 'zones'? Apologies might sound like a daft question but no idea where to start

degsod

I am looking at zwave radiator valves like these Z-Wave Danfoss LC-13 Living Connect Radiator Thermostat | Vesternet I already have a Fibaro home automation system so am goingto link it with these motion/light heat sensors Z-Wave Fibaro Motion Sensor Gen5 | Vesternet which i have in each room. There are cheaper options available

adam-burnley

I was interested in doing something similar, but wondered about the ROI timescales.  For instance, how much would running an efficient rad on a schedule save compared to running the same rad on a regular TRV?  Plus the system will have to work harder if rads are left cold most of the day.

I've not done any research and there may well be real world stats that show there are savings to be made within a reasonable time frame, but I'm a little sceptical.  Particuarly as there is always better technology just around the corner, so forking out on new and improved smart TRVs could get expensive!

neilball

I'd suggest looking at Honeywell Evo. This is designed as a multi-zone heating control system rather than a range of independent devices operating a common comms protocol. This means you get the best levels of heating control with the option of wider integration if you want it. For example the TRVs have a self-learning control strategy, learning the thermal characteristics of each room, to maximise comfort levels and minimise energy use. Honeywell have a long and varied background in HVAC control (they own some of the most well known and best respected controls brands in the industry) so you can rest assured they have implemented well designed and tested controls algorithms. This does mean that they do not have the industrial design of Nest nor based on open protocols such as z-wave, but it does offer some of the best levels of control with a wide range of specific control devices to cover all aspects of heating and hot water control.

The wireless controls from Honeywell go back nearly 20 years, and many of the devices from 15 years ago will still work with Evo now, so you've got a well developed, mature, reliable system too.

I'm not sure about the need for swapping out for new features - the controls either work effectively or they don't - HVAC control is a mature application, so there is not going to be some new clever method of heating control that makes your TRVs obsolete. There will be new user interfaces and integration options but I'd rather have the best levels of comfort and efficiency over a fancy looking stat or app that performs less well.

For example, the older Honeywell HR80s work as well as the more recent HR92s. The new models look much better, and have an easier to use UI, but they do not work any better at controlling room temperature than the 15 year old HR80s. And in turn the HR80 was a development of the HR50 which was available for several years before the HR80 replaced it. In this case the main change was to the wireless frequencies used plus the addition of "window mode" due to legislation that made this feature mandatory in some countries.

m3y

With the Honeywell evohome, do you need to have a radiator controller for each radiator in the house? I.e I would need 9 controllers plus the user interface and boiler modules?

m3y

Also does anyone know how the multi zone set up with hive is done? What is needed for this?

neilball

If you want full multi-zone you either fit a "smart"/wireless actuator on TRV body at each radiator or you have to plumb each room to a separate zone valve (only practical for new-build or major refurbs where you are fitting new pipework). Does not matter which control system you choose, you have to control the flow of heated water to each radiator/room independently to be able to control it as a separate zone.

If you have several radiators in a room there is usually a way to configure the setup to treat them as part of the same zone.

Also think about hot water control too if you don't have a combi boiler.

m3y

All sounds confusing to me lol, think the evohome would be my best bet albeit quite expensive

saintie1

How about something more basic than everything all controlled?  Why not split the house into two zones, one for the main living areas, the other for the bedrooms?  At the very least you will need to be able to control the flow going to the two zones and put in actuators on each line.  Two thermostats (one in each zone) and a controller.  All of these are relatively cheap but the biggest problem (and cost) could be intercepting the pipe work to separate the two zones.

neilball

That's why the wirelessly controllers/battery operated TRV actuators from Honeywell are so useful - fully room-zone your heating with no re-plumbing, minimal wiring, and no need to lift carpets/open walls & ceilings, expose pipework for plumbing works, redecoration afterwards etc. And if you want it is easy to take with you when you move house. In the meantime you get much better temperature regulation and energy savings of 25% or more. What's. it to like?