In the Beginning - The Central Heating

Our central heating / hot water is a standard system consisting of a boiler, hot water cylinder, thermostat (in the hall), programmer, 17 radiators (mostly fitted with TRVs), valves, pump and a tank in the loft. There is just one feed & return loop.

The programmer is used for both the heating and the hot water. It is set on a 24 hour basis.

Honeywell Thermostat	Honeywell ST699 Programmer	Potterton Profile 60E
Central Heating Pump	Typical TRV	Motorized Valves

In the Winter, the central heating is set to come on for a few hours in the morning and again in the evening with occasional boosts during really cold spells. When the central heating is activated, water is pumped around the whole house via a Grundfos pump.

Radiators are individually controlled by TRVs and are often left heating empty rooms - the biggest culprits are the living room, the utility room, my husband's office and the kids' rooms.

Hot Water Pump	Hot Water Timer

In addition, the hot water has a separate timer which is used to operate a pump responsible for delivering water to the whole house. When we moved in, I assumed that this was just to speed up the delivery of the hot water to more remote parts of the house. However, the reality is, that without this additional pump being activated no hot water ever gets delivered downstairs however long you wait for gravity to do its thing. Much of the pipework is concealed, so it is difficult to see what is going on. Plumbers have been puzzled by this too.

If the boiler is off and the pump is left running, a cylinder of hot water cools quite quickly despite no water being drawn off. This would suggest the circulation of the water is a huge waste of energy.

There are three main things I would like to achieve:

1. Create separately controlled heating zones (possibly down to individual rooms)
2. Operate the hot water pump from downstairs only when required
3. Control everything from a phone or tablet