NO CENTRAL HEATING ?

IF YOUR HOT WATER IS WORKING OK BUT YOUR HEATING IS NOT THEN THE FOLLOWING MAY PROVIDE A CLUE AS TO THE PROBLEM.

IF YOU HAVE A CONVENTIONAL SYSTEM WITH A HOT WATER CYLINDER, THEN THE MOST OBVIOUS REASON WOULD BE THE DIVERTER OR ZONE VALVE. YOU WILL EITHER HAVE A 3 PORT MOTORISED VALVE OR 2 X 2 PORT VALVES, THESE VALVES OPEN ON DEMAND FROM THE PROGRAMMER VIA THE ROOM THERMOSTAT AND DO GO WRONG QUITE OFTEN. SOME ENGINEERS WILL JUST CHANGE THE MOTOR ON TOP, BUT THIS IS FALSE ECONOMY, AS THE PART THAT MOVES INSIDE THE VALVE, GETS STIFFER OVER TIME AND CAUSES THE MOTOR TO BECOME OVERLOADED, SO IT IS BEST TO REPLACE THE ENTIRE THING.

THE ROOM THERMOSTAT CAN ALSO CAUSE PROBLEMS AND SHOULD BE CHECKED FOR CORRECT OPERATION, SO TOO THE PROGRAMMER. A FAULT  ON EITHER OF THESE WILL PREVENT THE MOTORISED VALVE FROM OPENING AND SENDING A SIGNAL TO THE BOILER AND PUMP, AND THEREFORE THE HEATING WILL NOT COME ON.

OTHER PROBLEMS ARE AIR LOCKS, RADIATORS WITH FAULTY THERMOSTATIC VALVES (THESE ALWAYS GO WRONG), THE PINS IN THESE GET JAMMED IF YOU LEAVE THEM OFF FOR ANY LENGTH OF TIME, SOMETIMES YOU CAN HIT THEM WITH A HAMMER AND THEY WILL POP BACK UP, BUT SOMETIMES THEY WILL NEED CHANGING.

THE IRONIC THING IS THAT THESE VALVES ARE NOW REQUIRED BY LAW TO BE FITTED TO NEW PROPERTIES TO REDUCE ENERGY CONSUMPTION, BUT THE PROBLEM IS THAT ONCE THEY ARE FITTED THE RADIATORS TEND NOT TO HEAT UP AS MUCH AND PEOPLE END UP TAKING THE TOPS OF THEM, THEREBY DEFEATING THE OBJECT!  TAKE MY ADVICE AND JUST GET MANUAL RADIATOR VALVES.

SLUDGE IN THE SYSTEM CAN ALSO CAUSE THE RADIATORS NOT TO HEAT UP OR ONLY HEATUP AT THE TOP, IF YOU HAVE THIS PROBLEM THEN THE SYSTEM WILL NEED POWERFLUSHING.

IF YOU HAVE A COMBINATION BOILER, THEN PROBLEMS TO LOOK OUT FOR ARE:-

CIRCULATION PUMPS NOT WORKING, C/H THERMOSTATS OR THERMISTORS NOT OPERATING CORRECTLY, THE FLOW SWITCH MAY NOT BE WORKING OR THE MICROSWITCH COULD BE FAULTY.

DIVERTER VALVE NOT OPENING, FAULT ON THE PRINTED CIRCUIT BOARD OR LOW PRESSURE IN THE CENTRAL HEATING CIRCUIT (SEE LOW PRESSURE SECTION FOR MORE ADVICE).

OTHER PROBLEMS LIKE SLUDGE OR AIRLOCKS HAVE ALREADY BEEN COVERED IN THE PREVIOUS SECTION.