Water Too Hot
Water heater producing scalding water? An overheating water heater is a safety risk. Find out why it happens, what to do immediately, and how to fix it — with same-day service available in Singapore.
What to Do Right Now
- 1 Turn off the water heater immediately — switch off at the power point
- 2 Do NOT use hot water outlets until the heater has been inspected
- 3 Check if your heater has a temperature adjustment knob — if it does, turn it down
- 4 Allow the unit to cool fully before attempting any manual adjustment
- 5 Call a licensed technician — do not open the heater casing yourself
Common Causes
Thermostat set too high or malfunctioning
Faulty thermostat stuck in the 'always on' position
Failed temperature sensor
Faulty mixing valve (if fitted)
Scale build-up causing localised overheating in storage tanks
Control board malfunction (digital heaters)
Why Your Water Is Too Hot — And Why It Matters
Water heater producing scalding output is more than an inconvenience — it is a genuine safety hazard. Water at 60°C can cause third-degree burns in 5 seconds. At 70°C, it takes less than 1 second. If your water is uncomfortable to touch within moments of opening the hot tap, switch off the heater and call for a repair.
In Singapore, scalding incidents from faulty water heaters are preventable. The two most common causes are easy to fix with the right tools:
Main Causes in Singapore Homes
1. Faulty Thermostat (Most Common)
The thermostat controls when the heater stops heating. If it fails in the “on” position, the heating element or gas burner keeps running beyond the target temperature. This is the single most common cause of overheating in both instant and storage heaters.
Fix: Thermostat replacement, $80–$120. Usually resolved in one visit.
2. Temperature Sensor Failure
The sensor reads the current water temperature and tells the thermostat when to switch off. If it gives incorrect readings, the heater may continue to heat thinking the water is cooler than it is.
Fix: Sensor replacement, typically $60–$100. Can be combined with thermostat replacement if needed.
3. Scale Build-Up in Storage Heaters
Heavy mineral deposits around the heating element create localised overheating — the element itself can reach very high temperatures while the thermostat reading (measured in the tank body) appears normal. The result is superheated water exiting the tank unexpectedly.
Fix: Descaling service + element inspection.
4. Thermostat Set Too High
Some storage heaters have a user-accessible temperature dial. If this has been turned up — by a previous tenant, during installation, or accidentally — the output temperature will be higher than expected. Check if your unit has a dial before calling for service.
What to Do Right Now
- Switch off the water heater at the power point (not just the heater switch)
- Do not use the hot water outlets
- Do not open the heater casing
- Call +65 8888 1111 or WhatsApp us for same-day service
Our licensed technicians diagnose and fix temperature control faults the same day in most Singapore areas.
Frequently Asked Questions
Why is my water heater producing scalding hot water?
Is scalding water from a heater dangerous?
How much does thermostat replacement cost in Singapore?
Can I fix an overheating water heater myself?
What temperature should a water heater be set to?
Need Professional Help?
Our licensed technicians can diagnose and fix your water heater issue quickly. Same-day service available across Singapore.