Practika pump wiring

This article must be read in conjunction with the User and Installation manual for this product

The Practika is different to many of the MCZ/ Red pellet boilers and stoves insofar as it does not have an in built circulation pump and inlet control/relief system: These components must be included as part of the overall hydraulic installation.

The logic of the Practika electrical control system dictates when the pump will operate depending on the temperature of the boiler water jacket, therefore the pump should be wired such that the boiler controls its operation. This will also allow the pump to circulate water when there is no demand but there is residual heat in the device, or the boiler is operating in Eco Stop mode, thus preventing overheating (for which a bypass circuit or heatleak radiator will be required).

The attached pictures show a simple wiring diagram and physical location of the pump wiring terminals on the motherboard. It is important to note that the motherboard does NOT provide electrical power to the pump itself, only a closed contact when circulation is required, to allow power to be drawn through it. Mains voltage must therefore be supplied to the pump from an external source.

Please also refer to the wiring diagram on page 32 of the User and Installation manual

Supplementary notes concerning A-Rated (High Efficiency) pumps

It should be noted that as A-rated pumps are now commonly used on installations, that if one is to be installed with this appliance, that the contacts on the motherboard that pass current to the pump are rated at a maximum of 3 Amps. As the start up (inrush) current of HE pumps can briefly exceed this value by some margin, it is Imperative that any current limiting or suppression devices / cables that are supplied with or can be obtained for the pump from the manufacturer, that limits current to this value (3 Amps) are present and installed. If not, then an appropriate contactor relay or other suitable device Must be installed into the circuit to otherwise prevent current through the contacts from exceeding this value.

Attachments:
Electrical-diagrams.pdf
Photo-of-connections-from-PCB.pdf