Potterton fault code E317, which may also appear as 162, is defined by Baxi as “Wrong power supply electrical frequency (Hz)” for the applicable Potterton Assure boilers. The controls have detected an electrical-frequency reading that they cannot accept, so the boiler may lock out.
The message does not mean that you should inspect wiring or buy a new control board. It identifies the type of signal the boiler has seen, but professional checks are needed to establish whether the cause lies with the supply reaching the appliance, the installation or the boiler itself.
What does Potterton E317 or 162 mean?
Electrical frequency describes how many cycles the alternating electricity supply completes each second. It is measured in hertz, or Hz. UK mains electricity has a nominal frequency of 50 Hz, and domestic appliances are designed around the expected supply.
When a Potterton Assure boiler shows E317 / 162, the boiler believes the frequency is wrong. Stopping is a protective response: the controls do not continue as though everything is normal when an important electrical reading appears implausible.
The display cannot tell a homeowner which component, connection or external event is responsible. It is possible for a supply disturbance and an appliance-side issue to produce similar symptoms, so the cause should not be guessed from the code alone.
Which Potterton boilers use E317?
Baxi’s current error-code reference places E317 / 162 in the group that includes:
- Potterton Assure Combi
- Potterton Assure System
Potterton has produced many other boiler ranges. Similar-looking displays do not guarantee identical codes, so check the complete model name before using this guidance.
Is this a gas fault?
E317 specifically concerns the electrical frequency the boiler is receiving or interpreting. It is not the manufacturer’s code for a failed gas supply. Nevertheless, the boiler is a gas appliance with electrical controls, and its casing should remain closed.
Do not confuse E317 with E385 / 165, which Baxi lists as undervoltage, or with ignition and flame-loss codes. Each has a separate meaning and requires its own evidence.
Safe observations you can make
You can collect useful details without carrying out electrical work:
- Take a clear photograph of the full display.
- Note whether the boiler shows E317, 162 or both.
- Confirm whether the appliance is an Assure Combi or Assure System.
- Write down whether the code followed a power cut, electrical work or a tripped circuit.
- Notice whether lights, clocks or other appliances behaved unusually.
- Record whether heating, hot water or both stopped.
If your exact user guide allows a reset, one reset may be used after an isolated interruption. If the fault returns, do not keep resetting or switching the supply on and off. A recurring E317 needs proper checks.
What not to attempt
Do not open the boiler, consumer unit or electrical accessories. Do not use a multimeter on live wiring, alter the fused connection, fit a different fuse or connect the boiler through an extension lead, adaptor or improvised power device.
Do not replace the printed circuit board on the strength of the code. The incoming supply, connections and boiler controls must be considered together before the right repair can be identified.
Could the wider power supply be involved?
The timing can offer a clue. If E317 appeared immediately after a power interruption, during generator use or while several appliances behaved strangely, tell the person attending. That does not prove the network caused the code, but it helps direct the checks.
Where lights repeatedly flicker, household clocks reset or multiple appliances are affected, advice may be needed from the local electricity network operator or a qualified electrician. If only the boiler is affected, the electrical supply at the appliance and the boiler still need to be assessed safely.
What happens during a repair?
The engineer will verify the exact model and code, review any stored faults and ask when the problem began. Appropriate tests can then establish whether the supply reaching the boiler is suitable, whether the relevant connections are sound and whether the controls are reading the supply correctly.
The result may point to the appliance, the local installation or an external supply issue. Checking before replacing parts is important because E317 describes a detected condition rather than naming a failed component.
Can E317 be intermittent?
Yes. A code associated with an electrical disturbance may disappear and later return. If the boiler starts after a permitted reset, make a note of the time and what else was happening in the property.
A temporary return to normal operation does not prove the fault is fixed. Repeated lockouts make heating and hot water unreliable and should not be managed by continual resets.
What if heating and hot water have stopped?
Do not bypass the boiler’s lockout. If temporary electric heating is needed, use equipment in accordance with its instructions, keep it clear of soft furnishings and avoid overloading sockets or extension leads.
For vulnerable occupants, young children or anyone with a medical need, make suitable arrangements for warmth while the boiler is out of service.
When should emergency action be taken?
E317 is not itself the manufacturer’s gas-leak code. However, if you smell gas, suspect carbon monoxide, see burning or scorching, or anyone develops headache, dizziness, nausea or breathlessness, move to fresh air and call the National Gas Emergency Service on 0800 111 999. Seek medical help if required.
What should I provide when booking?
Send a front-on photo of the boiler and display, the complete model name and a brief description of when E317 appeared. Mention power cuts, recent electrical work, generator use and any unusual behaviour elsewhere in the home. Leave the boiler and electrical equipment closed.
Ready to get the Potterton fault put right?
Choose a fixed-price boiler repair for a straightforward booking and professional attention to the E317 lockout.
Potterton E317 FAQs
Is 162 the same as E317?
For the applicable Potterton Assure models in Baxi’s current table, E317 / 162 are listed together as wrong power-supply electrical frequency.
Is E317 an undervoltage code?
No. Baxi lists E385 / 165 separately as undervoltage. Frequency and voltage are different characteristics.
Should I call an electrician or a boiler engineer?
Start by explaining the exact code and any wider power symptoms when booking. The evidence will show whether the next action belongs with the boiler, the local electrical installation or the electricity supply.
Can I keep resetting the boiler?
No. Follow the exact user guide once if appropriate, but do not repeatedly reset a recurring E317 fault.