Honeywell ST699

Product Information

The only reason I wasn't going to bother with downstairs was because we don't really have trouble with the heat levels downstairs, if anything it's hard to keep it warm even when heaters are on constantly as it is a large open plan space and has a very large bay window at one end and French doors at the other. They are used only by Mr Central Heating or the trusted partners we work with, where they are used for marketing, statistics and personalised ads. Eas to fix, theres a small hole bottom right hand corner, press a fine electric type screwdriver in and the bottom will come away. It's what a wire is connected to at each end that determines its function, not the colour of its insulation.

Oh and the valve that doesn't go into the cylinder has it's wire going via a smaller round junction box screwed to the bottom of the airing cupboard - not sure if this is just to extend the wire though? If so, these will be from the motorised valves and would be connected to the internal switches I mentioned earlier. Yes as a default I will just replace the wires to the exact layout of the Honeywell , utilizing the L N 3 and 4 terminals on the Hive. so if theres a power cut the controller will retain the clock info and timings and switch heating on as soon as power is back on.

Also wondering if I should connect the yellow cable ( comes from the yellow/green cables in the power wires) into the earth connection in the Hive.

I had a closer look at it at lunch time and noticed that the previous owners built a new window sill that is sitting (loose) over the original sill - I lifted it up and the original sill is cold to touch (that window is North facing too which doesn't help matters - there is still snow remaining in front of it even though the rest thawed a week or so ago! Is it a DIY job or something a professional should do, baring in mind I don't want to replace the whole system, just the timer/thermostat of the existing system? Don't see why two rows of terminal blocks are required; the norm is one row with 10 pairs of terminals.As I say, I looked at the replacement wiring diagram and it all looked straight forward, so I removed the cables and put them into the terminals indicated. This has lead me to think that while I'm replacing valves anyway I may as well use the opportunity to fit Thermostatic valves to all the upstairs radiators. HONEYWELL ST699 B1002 ELEC 24 HOUR PROG The ST699 time control programmer can be used as a replacement programmer on gravity primary or fully pumped systems.