Category: Boiler Fault Codes

The cost of a new boiler depends heavily on the type of heating system you choose. As a broad guide from the supplied 2026 pricing data, a fully installed boiler can range from around £1,800 to £5,000, with oil boilers starting slightly higher. The final amount can vary depending on the boiler model, output, existing…

A Baxi combi boiler contains a number of components working together to provide central heating and hot water. Parts such as the heat exchanger, pump, diverter valve, expansion vessel, sensors, gas valve and PCB all have different roles, and a problem with one component can produce very different symptoms. This guide explains the main parts…

If you can see water dripping through the tundish on an unvented hot water cylinder, it usually means one of the system’s safety or pressure-control devices is discharging water. The tundish itself is normally showing you that there is a problem elsewhere, rather than being the cause of the leak. Common causes can include an…

If your combi boiler’s hot water keeps changing from hot to cold, the problem may be caused by a restricted plate heat exchanger, an unsuitable water-flow rate, a faulty flow sensor, an inaccurate thermistor or a diverter-valve problem. A blocked plate heat exchanger is a common possibility, particularly when the central heating works normally but…

A boiler pump not working can prevent heated water from circulating through the boiler, radiators and heating system. Possible signs include cold radiators, slow heating, unusual humming or grinding noises, repeated boiler lockouts and circulation or overheating fault codes. However, these symptoms do not automatically prove that the pump has failed. Low pressure, trapped air,…

A boiler gurgling noise followed by a lockout often means condensate water is not draining correctly. During freezing weather, the most likely cause is an external condensate pipe blocked with ice. If the weather is mild, or thawing the pipe does not solve the problem, the internal condensate trap or hose may be blocked. Homeowners…

The right combi boiler size depends on two separate demands: how much heat your property needs and how much hot water your household uses. As a starting point, homes with up to 10 radiators and one bathroom often consider a 24–27kW combi. Properties with 10–15 radiators or greater hot-water demand commonly look at approximately 28–34kW,…

The Baxi 600 vs Baxi 800 and Main Eco Compact are closely related combi boilers from the same manufacturer group. They share important characteristics, including compact designs, stainless-steel heat exchangers and brass hydraulic components. However, they are not sold as identical products. The main differences are the available outputs, warranty length, included accessories and homeowner…

A radiator may remain cold because of trapped air, a closed or stuck valve, sludge, poor system balancing or a wider circulation problem. Where the radiator feels cold provides an important clue: a cold top commonly points to trapped air, while a cold bottom is more often associated with sludge or restricted water flow.Start by…