When combining Domestic Hot water and Radiators, a "MP" or manifold tank is used to store all the hot water in one unit

Tank Size / Facts

• Traditionally a 400Ltr Storage tank is used
• Tank dimensions are 900mm High x 900mm Round (Approx sizes used)
• When full of water - this tank will weigh up to 440Kg
• This system relies on Gravity and the tank MUST be installed higher than the stove / boiler 
• No pumps / valves / strainers can be installed between the flow and return lines from the tank to the stove
• One Tank can combine water for Hydronic Radiators / Domestic Hot Water and Solar Heated Water

These tanks are available all plumbed so you can combine:

Hydronic Water

• The Hydronic water is the same water heated by the Wood Boiler or Wood Stove that also is used in the radiators
• An Inhibitor is used in this water to prevent rust in your system and prolong the life expectancy
• A 22.5 or 45Ltr header tank is used to fill this system

Domestic Water

• This water is separated through Copper Manifold (or coil) available
• Domestic Hot water requires 4Kw of heat to heat (1Kw heats 100Ltrs) - this will need to be added to your hydronic Loading figures

• 18mtr and 36Mtr Manifolds coils available

Solar water

• Solar Heated water through Solar Panels
• This heated water can also be stored in this tank through an additional  Copper Manifold (or coil) coil in the base of the tank
• Flat solar panels or Tube Solar systems can be used
• Solar water has no impact on the Hydronic requirements and is a supplement to the Domestic Hot Water heating requirements

Electric Boost

• A 3.6 or 4.8 electric element 

• Electric  booster will only assist the domestic water

 Typical Plumbing

There are a number of ways to plumb these systems

The basic rules are:

• The Hot Water tank MUST be installed above the Wood Stove /Boiler
• The flow and return pipes MUST be on a fall (this is known as Gravity Plumbing)
• The Flow and return pipe MUST NOT have any valves of any kind installed
• The Thermostat is installed on the Flow line as close as possible to the Stove / Boiler
• The Pump is traditionally installed on the Return Line.

The system is designed to work in this way

Gravity systems is also known as Thermosyphon system : its based that Hot water is lighter than cold water - so as soon as there is a temperature increase: the hot water will naturally rise

As soon as the boiler or stove is alight, 100% of the water will naturally rise into the storage tank

- this natural circulation will happen because hot water is lighter than cold water

Once the water temperature reaches 70oC >75oC - the thermostat (which is on the hot flow line) will then turn the pump on (which is on the return line) and start to pump the water into the radiators

Depending on the set up (how many radiators you have) the pump does not use all the hot water... it Will only pump 40%

- 60% of the water to the radiators, the balance is continuing to go to the hot water storage for your domestic use

How the Domestic Coil Works

Water in storage tanks naturally laminates - the hot water is always hotter in the top 1/3rd or the tank

The "MP" coil is submerged in the hot water in the hottest part of this water and the heat from the storage (or hydronic water) is transferred through the copper pipe to the domestic water

Different length coils are used (18 or 36Mr) which will determine how much domestic water you have on demand

Adding Solar

By Adding Solar Hot Water to the system; you have created an "Off the grid System"

Different brands and your location will determine the solar impact on this system

The Solar WILL NOT assist the Hydronic part of the system : it will only assist with the domestic requirements