Why Is My Geyser Not Heating Water?

Short answer: if a geyser has stopped heating entirely, the cause is almost always one of three things — a burnt-out heating element, a tripped thermal cut-out, or a failed thermostat. All three are repairable, and none of them require replacing the geyser.

First, check the obvious

Before assuming a fault, rule out the simple explanations. Is the switch on and the indicator lit? Has the MCB for that circuit tripped? Has anyone turned the thermostat right down? In older buildings a loose connection at the isolator switch is common, and no amount of work on the geyser itself will fix it.

If the indicator light is on but the water stays cold, the supply is fine and the fault is inside the unit.

The heating element has burnt out

This is the single most common cause. The element is a metal rod inside the tank that heats the water. In parts of Kolkata with hard water it gradually accumulates scale, which acts as insulation. The element then runs hotter than designed to reach the same water temperature, and eventually fails.

The symptom is exactly what you would expect: power reaches the unit, the light works, nothing heats. Replacing an element is routine and is usually completed in a single visit.

The thermal cut-out has tripped

Every storage geyser has a thermal cut-out — a safety device that cuts power if the water gets dangerously hot. Some units have a small red reset button behind a cover.

Pressing it may restore hot water immediately, and that is where many people stop. It is worth understanding what actually happened: the cut-out tripped for a reason. Usually a thermostat has failed and allowed the water to overheat. Resetting the cut-out repeatedly without finding the cause removes your safety margin on an appliance that combines mains electricity with pressurised hot water.

The thermostat has failed

A thermostat tells the element when to switch on and off. When it fails it can stick open — so the element never runs and you get no hot water at all — or stick closed, which is what trips the cut-out. It is an inexpensive part and a quick replacement.

Heavy scale in the tank

Sometimes nothing has failed outright. Sediment collects at the bottom of the tank and around the element, reducing the usable capacity and slowing heating. A 25-litre unit starts behaving like a 15-litre one, and the water is lukewarm rather than hot. A descaling service restores performance without replacing any part.

Stop and call someone if you see these

Some symptoms are not a matter of inconvenience. Switch the geyser off at the mains and do not use it if:

• You feel any tingle or shock from the tap or shower fitting
• The MCB trips whenever the geyser is switched on
• There is a burning smell, or scorch marks near the connections
• Water is seeping from the body of the tank rather than a pipe joint

The first two usually mean the element has failed to earth. In a wet room that is a genuine electrical hazard, and it is not a repair to attempt yourself.

What you can safely check yourself

Confirm the power supply, check the MCB, and look at the thermostat setting. That is genuinely the extent of it. Opening the unit means working with mains electricity next to water, and on most models it also breaks the seal on the tank connections.

Repair or replace?

Repair is the sensible choice when the tank is sound and a single component has failed. Replacement makes more sense when the tank itself has corroded and is leaking from the body — that cannot be patched safely — or when an old unit is failing repeatedly. A technician should tell you which applies after inspecting it, not before.

Preventing it next winter

Most of the emergency call-outs we attend in December were avoidable in October. A geyser that has sat unused since March is asked to work hard for the first time in months, and everything gets tested at once: a scaled element, a thermostat that has not cycled, and dried-out seals. An annual service before the season — descaling, testing the thermostat and cut-out, checking the pressure relief valve and the anode rod — is the single most effective way to reach the full life of the tank.

Get it looked at

Call +91 82740 66348 for doorstep geyser repair across Kolkata. Tell us the brand and what the unit is doing and the technician will arrive with the parts most likely to be needed.

Frequently asked questions