Common Ariston water heater problems

No hot water from your Ariston water heater

Ariston's Singapore support page gives separate checks for storage heaters and instant heaters. For a storage heater, it lists the electric switch not being on, no power supply (check the cables, plugs and terminals), an activated thermal cut-out, a thermostat not fitted properly on the element, and a heating element that is cut off or short-circuited and needs replacing along with its gaskets.

The thermal cut-out cuts the power if the thermostat fails, so if it has activated, ask a technician to check the thermostat too.

For an instant heater, Ariston lists a power supply failure or the selector knob not being on, water flow too low to trigger the flow switch, and defective components. If the heating, ELCB or safety indicator is blinking or not lit, Ariston says to call for service. Low flow can come from a stop-cock valve that is not fully open, low inlet pressure, a jammed mesh filter, debris in the hand shower or a twisted hose.

Anything behind the casing is Ariston water heater repair work, not a DIY job. You can compare companies listed for water heater repair.

Tripping the power

If a storage heater's circuit breaker cuts out when you switch it on, Ariston points to an incorrect electrical power setting or an earthed element. Its fix is to test the element and replace it if necessary, which is work for a technician.

If the RCCB in your distribution board ("DB box") trips, EMA explains that an RCCB cuts off electricity when it detects a current leakage that may lead to an electric shock. EMA lists ageing or exposed wires, faulty electrical appliances and damaged insulation as causes, and says to test the RCCB once a month using its "Test" button. Either way, stop using the heater and leave it switched off.

EMA requires electrical works at consumers' premises, including repairs, to be carried out by Licensed Electrical Workers (LEWs). EMA says electrical work in an HDB flat needs a Licensed Electrician, the class of LEW approved for loads of up to 45kVA. You can check whether a person is licensed on EMA's ELISE portal. For help tracing the fault, see power trip repair.

Leaks and the pressure relief valve

Ariston says a storage heater's pressure relief valve releases water through a small outlet when pressure is too high, and that outlet should drain to the drainage system. If the valve leaks often, Ariston points to a defective valve or too much pressure. The fix is to replace the valve or install a pressure reducer, so leave it to a plumber or Ariston's service centre.

Leaks or rust at the cover, bracket or flange mean boiler perforation from corrosion, and Ariston's answer is to replace the heater. The cost depends on the job; see the water heater replacement cost guide.

Noise, smells and short cycling

Ariston links noise while heating, or frequent short on/off cycles, to scale on the element. Its remedy is to clean or descale the element, which is internal work for a technician. If a hissing noise increases substantially, Ariston advises contacting a plumber or its service centre.

A bad-egg smell has two possible causes on Ariston's list: bacteria, which calls for draining, cleaning and rinsing the tank, or a water temperature that is too low.

Maintenance and service options

Ariston advises replacing the magnesium anode in some storage series regularly, for example every two years, as a chargeable service. Ask its service centre whether this applies to your heater. Ariston's Singapore customer service page lists a hotline and a WhatsApp channel, open Monday to Friday, 9am to 5pm. If your heater is still under warranty, contact the manufacturer first.

For work outside warranty, PUB advises discussing the scope and cost first, asking for itemised quotes and getting at least three quotes. Prices depend on the job; see plumbing costs for a general picture.

When to stop and call a professional

Stop using the heater and get help if it trips the power, leaks from the tank, shows rust or gives off a burning smell. The guide to water heater warning signs covers more of these.

Electrical faults need an LEW. For plumbing, PUB says regulated water service and sanitary plumbing works must be done by a PUB Licensed Plumber, apart from listed simple works a handyman may do. Replacing the pipe between a stop valve and an instantaneous water heater is on that list. Pipework for a storage water heater is not, so use a Licensed Plumber for it. Engaging a plumber who is not licensed for regulated works has been an offence since 2018. When you compare plumbers, ask each one whether they are a PUB Licensed Plumber.

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