Water Heater Failure
Mains pressure storage water heaters regularly last for eight to ten years before they require replacement. If your hot water heater is nearing the end of its life cycle then internal defects may cause water temperature to fluctuate. This may call for replacement of the entire water heater or possibly a single component. If you have a gas water heater check the pilot light and the thermostat control . If the pilot light is sputtering or the thermostat control is set to the wrong temperature, use the guide linked above or adjust the thermostat to the required temperature. This may be a simple adjustment to get the hot water heater back to normal. If your water heater is electrical the thermostat setting would also need to be checked and in most cases with mains pressure storage water heaters gas or electric as required regulation they should have a mechanical tempering valve fitted to the hot water outlet plumbing. These valves should also be serviced or replaced if faulty and could be worth a call to the professionals at Australian Hot Water.
Water Heater Size
In addition to maintaining good hot water supply for the house hold needs, it really pays to make sure that your hot water heater is the right size for your household. It may be that an inadequately-sized water heater is the cause of your hot water temperature fluctuating. Essentially, if your water heater is too small it will have trouble keeping up with demand. This is particularly true for mains pressure storage water heaters. Consult with your local Australian Hot Water plumber and upgrade to a bigger system if it is necessary.
Pressure Balancing Valve
If you have been able to rule out any faults or issues with either gas or electrical heating components then it could be your pressure reduction valve that is causing your water temperature to fluctuate.The pressure balancing or reduction valve controls the water pressure in your plumbing system and balances water flow into the water heater. The temperature of water when multiple outlets are switched on at the same time could effected hot water supply to anyone outlet due to no enough pressure to serve all tap outlets at the same time.
If you notice fluctuations in water temperature when more than one outlet is open, it’s time to have your pressure reduction valve serviced or replaced to avoid serious burns.