Fresh Water Tanks
The FS1 and FS2 Fresh Water Tanks from TiSUN are high quality, highly efficient un-vented pressurised systems.
The fresh water tank features an internal corrugated stainless steel coil at its base which delivers legionella-free domestic hot water fed by mains pressure. They operate on the heat exchange principle which means that cold mains water is heated as it passes through the tank and comes out hot at the tap as opposed to conventional systems where direct stored water is fed out. This ensures fresh, bacteria-free hot water from the tap rather than stored water.
All tanks feature extremely high insulation (100mm polyester fibre fleece) ensures minimal heat loss.
The FS tanks are additionally designed to supply space heating (underfloor and radiators) directly from the tank. Pressurised systems such as heat pumps and boilers can be directly fed into the cylinder. Depending on tank option used, a further one or two indirect heat sources can then be incorporated. A single tank can accommodate multiple heat sources simultaneously (eg heat pump, solar and boiler).
Six sensor sleeve pockets offer advanced data logging potential – allowing you to read the temperature at different levels in the tank.
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| FS/1R Tank | FS/2R Tank |
Options
The two tank options in this range are the FS1 Tank which allows for one indirect heat input (eg solar) in addition to two direct heat inputs (eg heat pump, boiler). The FS2 Tank has a second input coil located in the top section of the tank which allows for the accommodation of a second indirect heat input (eg additional solar, wood burner, Aga, Rayburn – whatever you wish).
Sizes
FS1 tanks are available in 500 litre, 800 litre and 1000 litre size
FS2 tanks are available in 800 litre and 1000 litre size
Heat Loss Data
| The figures below are based on 60˚C storage temperature | |
| FS 500 | 1.74 kWh/day |
| FS 800 | 2.21 kWh/day |
| FS 1000 | 2.56 kWh/day |






