No Hot Water? 6 Things to Check Before Calling an Engineer
Waking up to no hot water is miserable, especially in winter. Before you pick up the phone, there are a few quick checks that might save you a call out fee and get your hot water running again in minutes.
1. Is your boiler actually on?
It sounds obvious, but check the boiler display. Is there power? Is there an error code showing? If the display is blank, check the fuse board. Boilers trip fuses more often than you would think, especially after a power cut.
2. Check the pressure
Look at the pressure gauge on the front of your boiler. If it is below 1 bar, the boiler will not fire. Repressurise it using the filling loop underneath until the gauge reads 1.2 bar. This is the single most common fix for no hot water.
3. Check the thermostat and timer
Is your hot water actually scheduled to be on right now? Many boilers let you control heating and hot water separately. Check the timer or programmer and make sure hot water is set to "on" or "auto" at the current time. Also check the temperature dial. If someone has turned it down, the water might be lukewarm rather than hot.
4. Try a reset
If there is an error code on the display, press and hold the reset button for 3 to 5 seconds. The boiler will attempt to reignite. If it fires up and stays running, check your hot tap after a minute or two.
5. Check if your heating works
Turn the heating on. If your radiators get hot but you still have no hot water, the problem is almost certainly the diverter valve. This is a small valve inside combi boilers that switches between heating and hot water. When it gets stuck or wears out, it cannot redirect water to the hot water circuit. This is a common repair that any engineer can handle.
6. Check the condensate pipe
In cold weather, the condensate pipe (the white or grey plastic pipe that runs from your boiler to an outside drain) can freeze. When it freezes, the boiler locks out and will not fire at all. Pour warm water over the frozen section of pipe, wait a minute, then reset the boiler.
Still no hot water?
If none of these checks solve the problem, there is a component fault that needs professional diagnosis. Common culprits include a faulty thermistor (temperature sensor), a failed diverter valve, a blocked heat exchanger, or a pump issue. Note down any error code and give us a call.
Need help with your boiler? Our Gas Safe registered engineers cover the North East. Get in touch today or call 07579 760536.