Hot Water Systems Redland Bay
Hot water repairs and installs in Redland Bay, including the valves that protect the system from high mains pressure. Gas, electric and heat pump units, with the old one removed when we replace it.
Water pressure and your hot water system
Mains-pressure hot water systems are built to work within a set pressure range. Too little and the showers are weak. Too much and the system works against itself: valves discharge, fittings wear and pipes knock.
The Plumbing Code of Australia sets a maximum static pressure of 500 kPa at any outlet inside a building, for both cold and hot water. Practice guidance from Victoria’s building and plumbing regulator explains why: pressure above that can cause water hammer, cause excessive noise, and shorten the life of appliances, taps and fittings.
Pressure isn’t the same at every house, and it fluctuates. The only way to know is to test it with a calibrated gauge at the meter outlet or a nearby garden tap.
What a pressure limiting valve does
A pressure limiting valve sits on the incoming cold water line and caps the pressure entering the house or the hot water system. Where the measured pressure is over 500 kPa, the guidance is that one must be fitted. Manufacturers set their own limits as well. Rheem’s guide for one range of electric storage heaters requires a pressure limiting valve when mains pressure exceeds 680 kPa with an expansion control valve, or 800 kPa without.
There’s a lower limit too. The same guide says supply pressure should be above 350 kPa for true mains-pressure performance. Below that, a mains-pressure system won’t deliver what it was designed to, and the fix may be on the supply side rather than the heater.
A common sign of high pressure is a relief valve that runs steadily for long periods, often at night. Never swap it for a higher-rated relief valve, as Rheem warns against doing that. The answer is a pressure limiting valve on the cold supply.
We fit approved isolation and pressure-limiting valves along with gas, electric and heat pump systems, under QBCC licence 15504687 and gas licence L90908. On a tank-fed property, the pressure comes from your pump instead, and we check that as part of the job.
Frequently asked questions
Can’t see your question? Call us and we’ll talk it through.
Call 0418 871 269What is the maximum water pressure allowed in a house?
The Plumbing Code of Australia sets 500 kPa as the maximum static pressure at any outlet inside a building, except fire service outlets. Above that, a pressure limiting or reduction valve is needed.
Why do my pipes bang when a tap shuts off?
That’s water hammer, and high pressure makes it worse. We can test your pressure and fit a pressure limiting valve if it’s too high, which also protects the hot water system.
Do I need a pressure limiting valve for a new hot water system?
If your mains pressure is above the manufacturer’s limit or the 500 kPa code maximum, yes. We test the pressure before installing so the new unit is protected and its warranty conditions are met.
My hot water relief valve drips all night. Is that pressure?
It can be. Rheem notes that a relief valve running steadily for long periods, often at night, can mean mains pressure is rising above what the heater is designed for. If yours runs steadily for long periods, a pressure limiting valve on the cold supply is the usual fix.
Can you check the pressure on a tank-fed property?
Yes. On rainwater, the pump and pressure vessel set the pressure, so we check those along with the hot water system.
Hot water in nearby areas
Not listed? We probably still cover your area, so give us a call.
Pressure problems or hot water trouble in Redland Bay? Call 0418 871 269.
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