How a multi fuel thermal store links heat sources
The Advance Appliances SFUTS universal multi fuel thermal store is built to take several heat sources at once. Boilers and wood burners feed the stored water directly, a bottom coil takes solar thermal, and two 3kW immersion heaters can run from solar PV or the mains. Each input has its own thermostat, so whichever source is available keeps the store hot.
Central heating is drawn from the store, which acts as a buffer for fast radiator or underfloor heat-up. Hot water comes through a large internal coil at mains pressure.
Wood burners
- Wood burners of up to 30kW output can be connected, according to the SFUTS installation guide.
- The store must sit level with or above the wood burner so water can circulate by gravity, and the connection must be in copper pipe, not plastic.
- The wood burner pump and control kit is fitted to every SFUTS. It recirculates water from the wood burner until it is hot, which prevents condensation and corrosion.
- Because a wood burner is only lit at certain times, Advance recommends a gas or oil boiler alongside it.
Solar thermal and solar PV
In the solar season, roughly April to September, Advance says solar thermal input should cover most hot water needs, with the solar controller set at up to 80°C in the tank. Solar PV can be wired to the immersion heaters, and the SFUTS PV versions come with a solar diverter that sends surplus PV power to the immersion.
Boilers and heat pumps
Any boiler used must be able to deliver 75°C and have a thermostat and energy cut-out so the primary flow can never exceed 100°C. Two pre-wired timers let you stop the boiler firing overnight and run the solid fuel pump later to keep heat in the store. A heat pump can be connected, but only with a boiler that tops the store up to 75°C.
Sealed or vented
The SFUTS is HETAS listed and works up to 3 bar, so it suits all heating circuits, including underfloor. As a sealed system it comes with a pressure relief valve, a thermal safety valve and a tundish, meets Part G of the Building Regulations and offers two levels of overheat safety. A vented version is available on request. The store is stainless steel, made in the UK and guaranteed for ten years. Details of HETAS listing are on the HETAS website.
- The Advance SFUTS links boilers, wood burners, solar thermal, solar PV and immersion heaters in one store.
- Each heat source has its own thermostat, and hot water comes at mains pressure.
- Wood burners up to 30kW can be connected, with a pump and control kit fitted as standard.
- Advance recommends a gas or oil boiler alongside an intermittent source such as a wood burner.
- It is HETAS listed, works sealed up to 3 bar, and is guaranteed for ten years.
Managing Director, Advance Appliances. 20+ Years experience