The heating of the house is to be done by using a wood stove. The woodstove is situated in the large room, which is the lounge, dining room and kitchen, but it will primarily heat water. The hot water is stored in a large tank (1,500 litres) upstairs and above the fire in a storage room. The water is to be used for underfloor heating as well as providing hot water for the usual uses of showers etc.
The large tank has three coils within it, one of which is stainless steel. Mains water is led through this coil, near the top of the tank, which supplies the domestic hot water in the bathroom and kitchen. It is heated, of course, by the water traveling through the coil which is surrounded by the hot water in the buffer tank, which has been heated by the fire in the wood-stove. By having the tank above the fire and using 28mm copper pipes between them, the tank water can be heated without electricity, to drive pumps etc., should it be necessary in say a power cut.
The water in one of the other tank coils is used for the underfloor heating and the third coil, near the bottom of the tank, will one day be used for solar panels when they can be afforded. (they were not in my budget).
Because of the size of the tank (1,500 litres) it had to be put into the building early on. You can see all the pipe inlets and outlets for the different coils etc.
This is the same tank with the grey insulation around it and the necessary pipework. The white box is not part of the plumbing but is a ventilation system with a heat exchanger.
There are four thermometers down one side of the tank. There is also a back-up electric immersion heater, which is not yet connected and which hopefully will never be needed!
This is the wood burning stove we are using. It has a water jacket on three sides as well as on the top so that 8 of the 11 kilowatt of heat gets transferred to the water and not the room. All the rooms have a underfloor heating system using the hot water produced.
Here you can see the copper pipes going up at an angle from the fire to the tank etc. On the right hand side you can see an aluminum flexible pipe connected to a valve. There is a large pipe from under the valve to the outside of the building through which air is drawn in for the fire. This is so the stove does not use or draw the warm air from in the house.
This is a picture of the insulated chimney pipe coming up into the attic space. It then passes up through the roof.
This is a picture from behind the stove. You can see the aluminum air supply pipe at the bottom. The very top pipe on the stove is where the heated water comes out and goes up to the tank above. The second pipe, the one you can see coming out of the wall (the top one coming through the wall) is the pipe bringing colder water from the bottom of the upstairs tank. The other pipes are safety features; the lower pipe coming through the wall is from the mains water and is connected to the valve with the wire attached. The wire is in turn attached to a thermostat, which will open the valve should the water in the jacket of the stove ever get too hot. Water will then flow through to cool the water in the stove. The other pipe coming out of the stove at the top with the red plastic cap is a pressure release valve which will open if the pressure in the stove hot water ever gets more than 2.5 bar.
This shows the pipes on the other side of the wall, in a cupboard. The top pipe is the hot water produced by the stove. If there is no electricity, say due to a power cut, the water will flow up by convection (i.e. by itself) and colder water will flow down the lower pipe to the stove. When there is electricity then the pump shown in the picture circulates the water, and cleverly, due to valves and a thermostat, it circulates it in a loop back to the stove until the water in the loop reaches 60 C, only letting water up to the tank when above that temperature. This means that the stove burns more efficiently and no condensation water is created in it due to very cold water entering the stove water jacket.
This little computer/control box does numerous things such as switches on the circulation pump when the water in the stove jacket gets hotter than 50C. It also tells you what pumps are on and what the temperature is at the stove and at the top and bottom of the tank etc. Should the stove get too hot or there is a power cut then it shuts the air intake pipe to the fire.
Tablehurst Straw House 