INSTALLATION INSTRUCTIONS
6.Pump
6.1Where a pump is fitted into the circuit it should be adjustable so that the flow can match the system requirements. Fit isolation valves to enable removal for servicing. The pump must have at least 1.5 meters of static head.
7.Electrical Supply
7.1Electrical connections must meet the requirements of national Building Regulations* and standards**, along with any European, local regulations and working practices that may apply. Should conflict occur between these instructions and these regulations then the regulations must be followed.
The connection to the mains supply should allow complete electrical isolation and only serve the heating circuit pump.
All water connections should be completed by a competent person to meet the requirements of local water authority
CONVENTIONAL Pipe work systems
All pipe work must be able to operate at above 100 degrees Celsius. Any pipe work installed in an exposed position e.g. loft space must have provision to prevent freezing.
Ensure the pipe work system has sufficient drain points to enable the complete removal of water for the purposes of servicing.
8.Gravity Pipe Circuit
8.1To prevent the risk of boiling it is essential to arrange the pipe work and position the hot water cylinder and heat leak radiator so that gravity circulation can take place when the pump is not running. Position the cylinder and the radiator vertically above the boiler with sufficient height to encourage gravity flow.
8.2Horizontal pipe work in a gravity system must have an incline of at least 5mm in every 1000mm and a minimum diameter of 28mm. Vertical pipe must have a minimum diameter of 22mm.
8.3Any motorised valves fitted in this circuit must return to the fully open position when the power is interrupted.
9.Pump Assisted Central Heating
9.1The most common arrangement is to have a pumped central heating circuit combined with a gravity hot water circuit. This arrangement requires careful balancing of the two in order to avoid the gravity circuit being starved when the pump is running.
To overcome this problem it is common practice to fit an injector tee where the pumped central heating return
Only use proprietary injector tees, homemade ones are difficult to get right.
9.2When installing a system that has pumped central heating and gravity hot water it is recommended to use all 4 boiler tappings. Each flow and return should be diagonally opposite each other.
10.Fully Pumped System
10.1In many installations (especially new build) a fully pumped system is the best choice to give increased control.
WARNING - To prevent the risk of boiling it is essential to arrange the pipe work and position the hot water cylinder and heat leak radiator so that gravity circulation can take place when the pump is not running. Any motorised valves fitted in this circuit must return to the fully open position when the power is interrupted.
11.Sealed (Pressurised) System
11.1Do not fit this appliance to sealed or pressurised systems or an unvented hot water cylinder.
12.Pipe work Diagrams
12.1See over for a typical layout of a pumped central heating and gravity hot water circuit.
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