my Baxi 105HE combi boiler works ok for hot water but in heating it runs for 5 seconds and off for 15 seconds constantly. temperature indicator only gets up to 50 C. Pump is working. Return water is only warm.Is it a circulation problem or is the stat faulty. How do you check

jon mosley, April 2008

it is likely your central heating temp sensor (thermistor) needs replacing. costs about 10 quid and takes 5 minutes to change

brian, October 2008