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  • Keston Boiler Error Codes / fault codes

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    • Keston Boiler Error Codes / fault codes

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  • Keston Boiler Error Codes / fault codes

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    • Keston Boiler Error Codes / fault codes

    Updated: October 9, 2022

    Keston Boiler Error Codes

    Who are Keston?

    Keston was originally founded in 1928. Their aim has always been to provide domestic and commercial heating. In 2006, the company was purchased by Ideal. Production then moved to Ideal’s factory, which is based in Hull.

    Keston boilers are ideal to be used in compact spaces such as flats or any properties which are small in size. It is perfect for properties in London. This is due to the fact that Keston boilers have a twin flue system that can make every job easier and simpler.

    You will have the ability to run the flue either vertically or horizontally from an elevation of 1.5 degrees. What is more, the flue can be extended up to 27 meters from the location of the boiler. This is done to achieve maximum flue flexibility. In addition, this process would allow for hassle-free and easy installation. It can also mean that your new boiler can be fitted in the most practical and suitable place in your property.

    What do Keston offer?

    With a Keston boiler you will get 7 years of warranty as well as a large range of compatible controls like the Keston 22mm/28mm system filter, the RF Electrical Programmable Room Thermostat and lastly the Mechanical Timer which guarantees a maximum performance from your boiler.

    However, in some cases, getting a new boiler might be more cost-effective than getting your old boiler fixed. Some issues might be costly to fix. What is more, a new boiler will probably be more efficient and can help you save both money and energy. That is why getting a new boiler is a good investment in the long run.

    Get a quote from Let’s Heat. We have a large range of products and our staff of Gas Safe engineers provide an excellent service that is both professional and reliable. In addition, we can help you get the boiler that best fits your house and heat requirements.

    What to do if I have a problem with my Keston Boiler?

    If you think that there is a problem with your Keston boiler, make sure to check the information below. We have prepared a list of the error and fault codes that you may see displayed by your boiler. These codes can help you identify the exact problem with your boiler. This will make it easier for you tell the Gas Safe Engineer what the exact issue is.

    C36 Combi Gas Boiler Error Codes

    Fault CodeThe Problem
    E01Ignition failure – the boiler has attempted to light 5 times and not succeeded – check the gas supply is on
    E02False flame – possibly a problem with the power supply
    E03Boiler overheat – check that any valves to the heating circuit have not been shut down, no air in the system and that the water pressure is correct
    E05Fan failure – boiler cannot detect fan rotation – check fan operation and both connectors onto fan
    E07Flue overheat – check combustion and flue temperature vs. return temperature – the flue temperature should be no more than 10C above return temperature. Possible heat exchanger fault.
    E08Flame circuit error – possible control box fault
    E09Valve drive error – possible gas valve or control box fault
    E10Control box errors – possible faulty control box
    E11The automatic test for calibration of flow and return sensors has failed – check both flow and return sensors are located on the correct pipes and are producing the correct readings
    E12 to E22Control box errors – possible faulty control box
    E23Water filling error – check water pressure sensor
    E24Water pressure lost 4 times in 24 hours – possible leak, check system and boiler
    E25Control box errors – possible faulty control box
    E26Flame drop out – check for obstruction of the flue and/or air terminals, blockage/freezing of the drain pipe or a low gas supply (LPG).
    E30Flow sensor short circuit – check connections to flow sensor
    E31Flow sensor open circuit – check connections to flow sensor are in place
    E32DHW sensor short circuit – check connections to domestic hot water (DHW) sensor
    E33Domestic hot water (DHW) sensor short circuit – check connections to DHW sensor are in place
    E34Mains supply voltage < 180V – may be a problem with your power supply
    E35Mains supply frequency incorrect – may be a problem with the power supply
    E37Water pressure error – increase the system water pressure
    E38Reset key fault – replace fascia PCB
    E40Water pressure too high
    E41Communication error between fascia and control box – check cables
    E43Return sensor short circuit – check connections to return sensor
    E44Return sensor open circuit – check connections to return sensor are in place
    E45Flue sensor short circuit – check connections to flue sensor
    E46Communication error between fascia and control box – check cables
    E99Flue sensor short circuit – check connections to flue sensor are in place

    S30 System Gas Boiler Error Codes

    Fault CodeThe Problem
    0The boiler is in standby mode awaiting either a central heating call or hot water demand
    CThe boiler has a call for central heating / hot water but the appliance has reached the desired temperature set on the boiler
    C and Burner LightThe boiler is operating for central heating / hot water
    F and Burner LightThe boiler is operating in frost mode
    F0Boiler Chip Card (BCC) not fitted
    F6Outside sensor failure
    F7Low mains voltage
    F9Printed circuit board (PCB) Fault
    L55 boiler resets in 15 minutes
    L6False flame lockout
    C0Boiler Chip Card (BCC) activation fault
    C2Boiler Chip Card (BCC) fault
    F1Low water pressure
    L1Flow temperature overheat
    F2Flame loss
    L2Flame loss
    F3Fan fault
    F4Control / No flow thermistor
    F5Return thermistor

    C40 C55 Combi Gas Boiler

    Fault CodeThe Problem
    EnnFault causing a boiler shutdown
    E00Flame detected when not expected – check boiler earth and probe condition
    E02No ignition after restart – check gas supply, gas valve operation and ignitor electrode spark generation
    E03Gas valve faulty or not connected
    E04Power has been reset whilst boiler was in lockout
    E11Internal electronics error – rest or replace control box
    E18Flow overheat – check water circulation
    E19Maximum return temperature exceeded – check circulation
    E25Flow temperature increased too quickly – check water circulation
    E30Difference between flow and return temperatures too high – check circulation.
    E31Flow thermistor short circuit – check/replace connections/thermistor
    E32Return thermistor short circuit – check/replace connections/thermistor
    E36Flow thermistor open circuit – check/replace connections/thermistor
    E37Return thermistor open circuit – check/replace connections/thermistor
    E44Low water pressure

    FAQs

    How long do Keston Boilers last?

    With the right amount of care and maintenance, a Keston boiler can heat your home for 10-15 years.

    Who makes Keston boilers?

    Keston’s was originally established in 1928 to provide domestic and commercial heating installations and servicing. In 2006, Keston was purchased by Ideal Heating before moving production to Ideal’s Hull manufacturing site in 2013.

    What type of boiler is a Keston C40?

    The Keston C40 and C55 use a variable speed combustion blower to deliver a premix of gas and air to a downward firing burner in a high efficiency, single pass heat exchanger. The flue system is room sealed and fan powered.

    How do I increase the pressure on my Keston boiler?

    The most common Keston boiler fault is low water pressure. The amount of water in your boiler and the water pressure are directly connected. So, if you add water, you be able to also increase the pressure.

    Where are Keston Boilers made?

    An early pioneer of condensing boilers, Keston was purchased by Ideal Boilers in 2006. Boiler production was moved to Ideal’s Hull manufacturing site in 2013 and all Keston boilers since have been designed, developed and manufactured in the UK.