Which faults are common on Potterton boilers?
Potterton is a long-established name in British heating, and its boilers turn up in Birmingham homes of every age: current Assure combis and system boilers in newer installations, and older Promax, Performa, Suprima and Titanium models still running in plenty of houses. Because the brand has changed hands and ranges over the years, the most useful thing you can do before anything else is find the model name, then use the right manual.
Pressure. On the Assure range, low pressure shows as E118, meaning the system has fallen below 0.5 bar. Topping up through the filling loop usually restarts the boiler. If it keeps falling, find the leak rather than topping up week after week. See boiler losing pressure.
Ignition. E133 is a gas supply fault: the boiler could not light. Start with the gas supply and prepayment credit, and in a frost check the condensate pipe. The same code and checks apply on Baxi boilers, so our E133 guide covers Potterton Assure owners too. The frozen condensate pipe guide shows how to thaw a pipe safely.
Circulation. E110 and E125 both mean water is not moving through the boiler as it should. Air in the radiators, closed valves, sludge or a failing pump are the usual causes. See cold radiators.
Older models. Some older Potterton boilers report faults with flashing lights, and the oldest have a pilot light rather than electronic ignition. If yours has a pilot that will not stay lit, see pilot light keeps going out.
Servicing a Potterton boiler
An annual service is the best way to keep an older Potterton running safely and to keep a newer one’s guarantee valid. It covers combustion, the flue, seals, the condensate trap and the safety devices. See boiler servicing.
When should you get an engineer?
If the same code returns after one reset, if a fan or overheat code keeps appearing, or if you see water inside the casing, send an enquiry. Include the model name, the code or light pattern, and the boiler’s approximate age. A local Gas Safe registered engineer will diagnose the fault, check whether parts are available for older models, and give a price before any work starts. If a newer Potterton is still under guarantee, contact the manufacturer first.