PressureRelief Valve

20 Carr Road, Three Kings Auckland, New Zealand PO Box 27-555, Mt Roskill Auckland 1440 Ph: +64 9 624 1115sales@macdonaldindustries.co.nz

Water heater pressurerelief valvefailure symptoms

Where floor, sink or shower wastes or gully traps are infrequently used due to remote location or where high ambient temperatures or high airflow movements are likely to cause excessive trap dry-out, the MacDonald Model SV1/TP should be installed.

Because the SV1/TP does not rely on pressure drops, it is able to maintain trap seal even when the building is unoccupied.

The MacDonald SV1/TP electronic timer controlled trap primer is designed to maintain a permanent trap seal in floor wastes.

Mechanical trap primers work when other plumbing fixtures, such as a basin tap, are operated thus initiating a pressure drop in the supply line.  The inherent failure of these types of devices to provide the necessary seal, is because the area where trap dry-out is most likely is where taps and valves are not being used anyway.