Oil boiler not firing? What to check before you ring

An oil boiler that will not fire on a cold morning is no fun, especially out in the country where the nearest help can feel a long way off. Before you pick up the phone, there are a few safe checks worth doing. They will not fix a faulty boiler, but they do rule out the simple things.

1. Is there oil in the tank?

It sounds obvious, but it is the most common cause. Tank gauges are not always accurate, so if you can, check the level with a dipstick. If the tank has been run very low, the boiler may also have drawn up sludge from the bottom, which can block the filter even after a delivery.

2. Is the boiler being asked to come on?

Check the programmer or timer is calling for heat or hot water, the room thermostat is turned up, and any batteries in wireless controls are not flat. Make sure the power to the boiler is on at the switch.

3. Has it locked out?

Most oil boilers have a lockout light and a reset button. If the light is on, you can press reset once. If the boiler lights and stays lit, keep an eye on it and let us know, because something made it lock out in the first place.

Do not keep pressing reset. If the boiler locks out again, leave it. Repeated resets can flood the combustion chamber with unburnt oil, which turns a simple repair into a bigger one.

4. Has the oil supply been shut off?

There is usually a valve on the supply line near the tank and another near the boiler. If anyone has been working near them, check they are open.

When to stop and call us

• It locks out again after one reset
• You can smell oil or fumes
• There is oil on the floor or around the tank
• It lights but makes a rumbling or banging noise

Turn the boiler off and ring 07712 646488. Our team is now registered to work on oil boilers, and we will arrange a visit to find the cause. Tell us the make of the boiler and what it is doing when you call, as it helps us come prepared.