Cost Advisor

Priority plumbing, Did your plumber get it right?

September 27, 2014

Freezing when someone flushes the toilet? Low Pressure when running a bath? These things can only happen if your plumber does not install your plumbing correctly! Giving the fixtures the right priority will save a lot of yelling out of the shower later.

Correct plumbing, All plumbing installations must comply with New Zealand Building Code requirements. Remember that the plumbing for a hot water cylinder is determined by water pressure and not by the fuel used for heating. For a domestic mains-pressure hot water system, use the same pipe sizes as for a low-pressure system. For a commercial installation, pipe sizes are determined by the number of cylinders used and by the rate of draw-off.

A 20 mm cold water supply is recommended from street to cylinder. Note that the cold water piping is taken directly to the water heater before going on to any internal draw-off point in the house. Both hot and cold pipes should run parallel from the water heater and directly to the shower. The manufacturers recommend a 20 mm hot pipe and 20 mm cold pipe directly to the shower. All other draw-offs should run from a single 15 mm line teed into the 20 mm line feeding the shower, as shown in above In this way, the shower always gets priority, and all outlets achieve equal pressure and equal resistance to flow in both hot and cold lines at each outlet. This is particularly important in providing good temperature control to showers.

Beware of existing plumbing systems that give priority to the bath taps. You may need to alter some of the pipework to overcome this problem.You may install plastics pipes only when they are approved for use by the Building Code.Failures have occurred through poor installation and can also occur through over-pressuring or overheating.

For any advise on plumbing for your new home contact Euro plumbing


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