It accepts the extra volume created when system water heats up, helping control pressure in a sealed circuit.
Pumps, Filters and Pressure Parts for Heating Systems
A heating system can lose performance when water circulation slows or debris reaches the boiler. MacBlair lists circulating pumps, magnetic filters and expansion vessels in its central heating range. These parts handle different jobs: the pump moves water through the circuit, the filter collects debris and the vessel accommodates water expanding as it heats.
The listed pumps include 5, 6 and 8 metre head options, while filter and inhibitor packs come in 22mm and 28mm versions. Expansion vessels cover several capacities, including separate potable-water models. Match each part to the system specification rather than choosing by appearance. A filter on the return pipe works alongside the right system inhibitor and cleaner to protect the circuit.
A replacement pump or vessel should be specified against the existing boiler and pipework, with pressure and flow checked by a competent installer. The wider pipe and fittings range covers the connections used when renewing sections of the circuit. If a system repeatedly loses pressure, diagnose the cause before fitting a new component.
Central Heating FAQ's
Match the required flow, delivery head, connections and control mode to the existing system. An installer can check the system design.
It traps magnetic debris such as magnetite carried around the heating circuit. Some filter designs also collect non-magnetic particles.
No. A filter removes circulating debris; inhibitor treats the water to reduce corrosion and scale. Follow the boiler manufacturer’s guidance.
No. A leak, failed valve or lost vessel pre-charge can produce similar symptoms. Have the fault diagnosed first.