Boiler Repairs BirminghamGet a quote

Boiler fault guide

Why Won't My Boiler Fire Up?

A boiler that will not fire up usually has one of four problems: no gas reaching it, often a prepayment meter out of credit; the controls not asking for heat; a frozen or blocked condensate pipe; or an ignition fault such as a worn electrode or failing gas valve. The first three you can check yourself. Ignition faults need an engineer.

Last updated:

Get a quote

All gas work is carried out by Gas Safe registered engineers.

Get a quote for your boiler

Sending an enquiry is free and there is no obligation. Tell us the fault and your postcode, and we will be in touch.

Please enter your name.

Please enter a valid email address.

Please enter a Birmingham-area postcode, for example B13 9AA.

That number does not look right. Leave it blank if you prefer email.

Please tell us briefly what is wrong (a sentence is enough).

By submitting this form you agree that we may pass your details to a local Gas Safe registered engineer so they can contact you about your enquiry. See our Privacy Policy.

Is it not getting power, not being asked, or failing to light?

It helps to work out which of three things is happening:

  • Nothing on the display. The boiler has no power. Check the fused spur switch next to it and your fuse box.
  • Display on, but no attempt to fire. The boiler is not being asked for heat, or it is blocked by low pressure. Check the timer, thermostat and pressure gauge.
  • Clicking or a fan running, then a fault code. The boiler is trying to light and failing. That points to gas supply, condensate or ignition.

What are the common causes?

  • Gas supply. A prepayment meter out of credit, a closed gas valve after work in the house, or a supply problem in the street. If the hob will not light either, it is the supply rather than the boiler.
  • Controls. A timer reset by a power cut, a thermostat with flat batteries, or a smart thermostat that has lost its connection.
  • Low pressure. Many boilers will not attempt to fire below about 1 bar.
  • Frozen or blocked condensate pipe. Common in Birmingham cold snaps. The boiler may gurgle and then lock out.
  • Ignition and flame detection. A worn spark electrode, a flame sensing electrode that cannot detect the flame, a faulty ignition lead or a sticking gas valve. Worcester Bosch shows this as EA, Vaillant as F28 and Ideal as L2.
  • Fan or flue problems. The boiler checks the fan and flue before lighting. A fan fault or a blocked flue stops ignition for safety.

What can you safely check yourself?

  1. Check the power at the fused spur and fuse box.
  2. Check the controls: timer, thermostat and any app.
  3. Check the pressure gauge.
  4. Check the gas: does the hob light, and is a prepayment meter in credit?
  5. In freezing weather, check the condensate pipe outside and thaw it with warm water if frozen.
  6. Reset once. If the same code returns, stop and send an enquiry.

What happens next?

If all of the above checks out, the fault is with ignition, flame detection, the fan or the gas valve. An engineer will test the gas pressure at the boiler, the electrodes and leads, the fan and the condensate trap. Electrodes and leads are often inexpensive parts. You will get a price before any work starts.

What will the repair cost?

It depends on the part. Most boiler repairs cost £100 to £500 at typical UK market prices. The boiler repair cost guide breaks it down by fault, and the engineer gives you a price before any work starts. Send an enquiry to get one.

Boiler won't fire up: common questions

Why is my boiler clicking but not igniting?

The clicking is the igniter making a spark. If the boiler clicks but never lights, either gas is not reaching the burner, the flame is lighting but not being detected, or the condensate route is blocked. After a few attempts it will lock out and show a code.

What should I check if my boiler won't turn on at all?

Check the power at the fused spur and the display, then the timer and thermostat settings. If the display is blank, check your fuse box for a tripped switch. If it is on but not firing, check the gas supply and pressure gauge.

Can a prepayment meter stop my boiler working?

Yes. If the meter runs out of credit, or the emergency credit has been used, no gas reaches the boiler. Top up and reset the meter as your supplier instructs, then reset the boiler once.

Related guides