Gas geyser not igniting when hot water is opened
If a tap runs cold while your gas water heater stays silent, clicks without lighting or displays a lockout, we can discuss a suitable gas geyser fault assessment.
Based in Laser Park, Roodepoort · Enquiries across Gauteng
What the water-heater symptoms mean
Instantaneous gas water heaters typically respond to a water demand and then start a defined ignition sequence. A fault in demand detection, ignition, controls or the wider supply can interrupt that sequence. The pattern at different taps and the appliance’s exact model help us distinguish a genuine heater defect from a water-flow issue.
No response when the hot tap opens
If the heater does not attempt ignition, ask whether any other hot outlet triggers it. A low flow or a sensing problem may prevent some units from initiating combustion. Record whether the display wakes up and what happened before the fault. Do not open sealed chambers or adjust the water inlet assembly yourself.
A click or fan starts but no flame appears
Some models run a fan or ignition system before lighting. A start-up sound does not prove the burner has received safe fuel supply or confirmed ignition. Tell us if the appliance displays a code, retries once or locks out completely. This helps a competent technician select the appropriate checks.
Only the shower fails to start the heater
A shower mixer and a basin tap may pass different amounts of hot water. A recent shower-head replacement or mixer fault can change the demand seen by an instantaneous heater. We consider the water-side behaviour alongside the appliance rather than assuming that a cold shower always means a broken gas burner.
Battery-powered versus mains-powered models
Some units incorporate replaceable user-accessible batteries while others use fixed electrical supplies. The manufacturer’s instructions determine which checks are suitable for an owner. If the heater requires access to electrical terminals, combustion components or the gas supply, stop and use an appropriately qualified person.
Failure after a cylinder change
If the heater stopped starting at the same time as other gas appliances, report that timing. There may be a common supply-side issue, but it is not safe to assume pressure is too low or to swap regulators arbitrarily. Regulator suitability and installation conditions must be assessed within the required registered scope.
Lockout can protect against unsafe operation
Automatic shutdown may occur because the appliance cannot verify correct operation. Repeated resets or attempts to hold controls open can mask an underlying hazard. Soot, exhaust odour or unexplained repeated lockout requires stopping use and seeking qualified assistance, especially with indoor or enclosed installations.
Book the right type of gas geyser inspection
Provide the brand, displayed error, indoor or outdoor location, water outlets affected and whether any ignition noise occurs. We can discuss possible assessment steps and confirm service availability. A telephone enquiry cannot establish compliance, component condition or the final repair cost.
Answers before you book
Why does the basin trigger heating but the shower does not?
The two outlets may deliver different hot-water flow; the mixer and heater need assessment.
Does clicking prove the heater has enough gas?
No. Ignition activity does not confirm safe supply or stable combustion.
Should I repeatedly reset a locked-out heater?
No. Persistent lockouts require model-specific qualified assessment.
Find the right appliance service
Choose the fault or appliance that matches your situation, or contact our team to discuss the symptoms.
Discuss your gas water-heater issue
Share the appliance model, symptoms and your suburb. We will discuss the appropriate next step and available service arrangements.