Glow Worm F75 Error: Causes and Solutions

What Does the Glow Worm F75 Error Mean?

The Glow Worm F75 error means the boiler’s pressure sensor is not working correctly. This sensor measures the water pressure in the system and sends this information to the boiler’s main control board (PCB). The Boiler f75 Issue is a common cause of the error, as the PCB ensures the boiler runs safely. If it detects a problem, it shuts down the boiler and displays the F75 error to prevent damage.

Water pressure is the force at which water moves through the system. The normal range is between 1 and 2 bar. When the pressure sensor fails, the PCB cannot confirm the pressure, so the boiler locks itself to prevent further risks.

Common Causes of the Glow Worm F75 Error

1. Faulty Pressure Sensor
   • The most common reason for the F75 error is a faulty pressure sensor.
   • If the sensor has an electrical issue, it may stop working, leading to an error.
   • A sign of a faulty sensor is that the pressure gauge does not change when the heating starts.
2. Blocked Pressure Sensor
   • Tiny debris, such as rust and sludge, can block the small opening of the sensor.
   • Over time, this buildup may prevent the sensor from reading pressure correctly, triggering the F75 fault.
3. Low Water Pressure
   • While less common, low water pressure can cause the F75 error.
   • Pressure drops naturally over time, but a leak or faulty component can also be responsible.

4. Faulty Heat Pump
   • Since the F75 error relates to water circulation, a broken heat pump could be the cause.
   • Signs of a faulty heat pump include vibrating or clanging noises when the boiler starts.
   • Possible reasons for pump failure include blockages, worn-out bearings, or incorrect speed settings.

Can You Fix the F75 Error Yourself?

In most cases, fixing an F75 error requires a professional. However, you can try two things before calling an engineer:

1. Reset the Boiler
   • Hold down the power button for five seconds.
   • The screen will flash a symbol, and the boiler will restart.
   • Check if the fault code disappears and if the boiler works normally.
2. Check the Water Pressure
   • If the pressure is too low, you might have to increase it.
   • Follow your boiler’s manual for instructions on increasing the pressure.
   • If the issue continues, call a professional.

Cost of Fixing the F75 Error

The cost of hiring a heating engineer varies depending on the issue:

• Topping up water pressure: £30 – £60
• Replacing a pressure sensor: £55 – £175
• Fixing a blocked sensor: £30 – £120
• Replacing a heat pump: £230 – £420
• Fixing a boiler leak: £60 – £240
• Replacing a boiler: £800 – £1,800

Labour costs differ across the UK, with higher prices in areas like London. If the boiler is beyond repair, a replacement may be necessary.

Getting a New Boiler

If you need a new boiler, look for options with:

• Gas-safe installation within 24 hours
• Competitive pricing and price match guarantees
• Flexible payment plans, including interest-free finance
• Up to 12-year warranty on selected boilers