Hello, I'm finally getting near to replacing the dreadful Keston C25 that I've had for a number of years now and am getting a couple of quotes from two local installers both of whom are proposing Worcester Bosch - most likely Greenstar 30 or 40 CDi Regular or the FS models.
The existing system is 2 zones (upstairs and downstairs) plus water heating - the system is open vented. The existing controller is Horstmann ChannelPlus Xl controlling the three zone valves. The zone valves are old and will be replaced and an automatic bypass installed but otherwise the radiator/pipework will remain much the same.
All the radiators have Drayton TRVs except for 3 upstairs (bathrooms and landing) and one downstairs (hall) and I'm told that I will need to have two room thermostats - one for each zone. These TRVs will probably be replaced except for a couple which are very recent because they are/have shown signs of sticking over the recent years.
I would like to improve the temp. control throughout the house, at least by having all radiators controlled by TRVs but feel that I can probably save energy consumption by having some more specific controls - e.g three of bedrooms are only used a few times a year for guests and the bathrooms get too hot when the heating generally is running all day in cold weather.
So I'm looking for suggestions for a control approach that it would make sense installing at the same time as the new boiler and that would work sensibly with the existing system. I'm wondering about controlling some of the radiators with wireless/programmable TRVs and linking groups of radiators (living room, hall, kitchen for example) to a single thermostat and similarly upstairs.
I would appreciate ideas and/or pointers to helpful discussions elsewhere that I can consider whilst we wait till April/May time (assuming the Keston doesn't fail completely before then). I have tried to review threads on this newsgroup and via google but feel that I need some practical and current inputs if poss. Sorry for verbosity but have tried to cover questions that might be asked of me in advance.
Regards, Colin