Potterton Boiler E128 Fault Code
The Potterton fault code E128 flame and/or ignition failure Q & A or require an engineer for an emergency boiler repair.
The Potterton Boiler Fault Code E128 Error Common Q & A
Just below, we have a list of common questions relating to the E128 fault code on the Potterton boiler.
- What does the E128 fault code mean on my Potterton boiler
- Is it likely that my boiler will need to be replaced if the E128 fault code is being displayed?
- Is it dangerous to reset my boiler if the E128 fault code is being displayed?
- What would cause the flame or ignition to fail so many times?
- If an airway isn’t clear, how will this affect the boiler’s operation?
- What does the fan have to do with an ignition or flame failure?
- How does the gas valve work, and how could it lead to the E128 fault code being displayed?
- Is there a fix for a gas valve that’s sticking?
- What does the heat exchanger have to do with a flame failure?
- How will my boiler engineer check to see if gas pressure is correct on my boiler?
What does the E128 fault code mean on my Potterton boiler
The E128 fault code on Potterton boilers relates to a flame and/or ignition failure. After noticing the fault, the boiler will attempt to re-fire or re-establish the flame up to a maximum of 12 times. Once there have been 12 flame failures, the boiler will lock out and display the E128 fault code on the display panel.
Is it likely that my boiler will need to be replaced if the E128 fault code is being displayed
There’s a good reason why only Gas Safe registered engineers are legally allowed to work on gas appliances like boilers; they’re dangerous.
And, whilst many faults relate to problems that aren’t potentially dangerous, this isn’t one of them. Any fault that involves ignition or gas related problems is a potentially dangerous one, and that’s the case with the E128 fault code on your Potterton boiler.
Is it dangerous to reset my boiler if the E128 fault code is being displayed
There are few boiler component faults that could be the root cause of the problem, as well as the gas supply. Typically, we don’t find that the E128 fault code is one that leads to a new boiler being needed.
What would cause the flame or ignition to fail so many times
Some boiler fault codes are incredibly specific. For instance, they might show exactly what the problem is, and the part that needs to be replaced. However, that’s not the case with the E128 fault code, as there could be one of a dozen or more things that are contributing to the problem.
For ignition failures (establishing a flame), it’s likely the cause is with the ignition lead or probe. If it’s not, there are plenty of other explanations, many of which could also be the cause of a flame failure during operation.
You’ll need to call a qualified Gas Safe engineer, and they’ll be able to check:
- Airways are clear, including the flue and condensate pipe
- The fan is operational
- The gas valve isn’t faulty or partially opened/closed, and is adjusted incorrectly
- The heat exchanger is free from debris
- Gas pressure to the appliance is sufficient
If an airway isn’t clear, how will this affect the boiler’s operation
There are two main airways to consider; the flue and the condensate pipe.
The job of the flue is to allow a low-resistance path for flue gases to escape. If this becomes blocked, flue gases can’t vent from the boiler, and the appliance becomes dangerous.
After the blockage, the air pressure switch will notice the difference in air pressure. It feeds back this information to the printed circuit board (PCB). If the PCB recognises the reading as not in working tolerance, it locks out the boiler as a safety mechanism.
And the same goes for the condensate pipe (usually the small white pipe on the exterior of your property). Instead of fumes, this helps condensed gases escape from the boiler. Typically, this airway becomes blocked in the summer months, as the pipe is prone to freezing.
For the boiler to work, these airways need to be free from obstruction.
What does the fan have to do with an ignition or flame failure
A boiler’s fan isn’t a device to stop the boiler overheating. Instead, the fan creates a draught so that gases can escape via the flue. If the PCB recognises the fan isn’t working, like an airway blockage, it’s going to cause the boiler to be dangerous, so it locks out.
How does the gas valve work, and how could it lead to the E128 fault code being displayed
Working inline with the PCB, the gas valve’s job is to supply sufficient gas to the boiler’s burner. That means an increased supply when you turn up your heating thermostat or turn on a tap, and decreased (or zero) supply when you turn down/off your heating and taps.
The problem with gas valves is they have moving components. And, these moving components are prone to sticking. That could mean that the gas valve remains partially open (when it should be closed) or remains partially closed (when it should be fully open). That’s not going to be providing the burner with sufficient gas and will lead to your boiler locking out.
Is there a fix for a gas valve that’s sticking
By removing the gas valve from the boiler, an engineer can usually free the valve. But, they’ll want to be certain that it’s completely operational. If they’re not happy with the valve, it’s likely they’ll suggest having it replaced.
There’s a significant difference between a gas valve that is sticking and one that’s been incorrectly adjusted. If the adjustment is incorrect for your boiler, your engineer will be able to rectify the problem without having to go through the process of a costly replacement.
Unfortunately, replacement parts on boilers are not particularly cheap. In the case of the gas valve, you should expect to pay somewhere in the region of £300 including labour.
What does the heat exchanger have to do with a flame failure
The heat exchanger is what water passes through to be heated, before the pump circulates it around the heating system. And, it’s a place where debris from heating sludge can build-up in quantity.
When there’s a build-up of debris in the heat exchanger, that’s going to lead to restricted circulation. Water stays in the exchanger longer than it should, and it overheats. When the thermistors (that monitor temperature) notice a water temperature that’s too high, they communicate with the PCB and it locks out.
Typically, we find alongside heating sludge, limescale is a problem that affects heat exchangers. Your boiler engineer will be able to take apart your boiler and clean the heat exchanger. Cleaning is all that’s necessary, if the heat exchanger hasn’t been caught too late and has suddenly cracked. A cracked heat exchanger will need to be replaced.
How will my boiler engineer check to see if gas pressure is correct on my boiler
There are two places your boiler engineer needs to check for gas pressure. The first is from the meter, and the second is to the boiler. By testing these two sections of the gas run, it can help them to isolate the issue.
In colder months, we find that the regulators on gas meters can freeze. But, there’s always the possibility that the gas pressure being supplied by the utility provider is to blame, and that’s something that they need to fix.
Other Potterton boiler issues
For more boiler issues regarding the Potterton Boiler then please visit the Potterton Boiler Problems And Cures page.