Ideal Boilers (caradon ideal)
Classic Combi and Classic NF
| Problem | Solution |
| Boiler cycling on/off | Wax thermostatic capsule on flow pipe can stick, preventing heating from coming on |
| Pressure problems | Flexible pipe to vessel can block causing pressure swings up and down |
| Overheating in water mode | The internal bypass may be blocked, there is no pump over-run on this model, so after demand the residual heat goes through the bypass by gravity |
Isar Range (M30/100 and HE Models)
| Problem | Solution |
| HF. (there is a dot after the HF) | Detection probe error, or lead has shorted to earth |
| Display symbol meanings | 0= No demand at rest t=Preheat from cold d=hot water demand, or preheat on later models C=central heating demand |
| 3 dashes in display | Appliance has overheated, may have been an L9/H9 overheat prior to this. Check operation of pump, make system is filled and vented, may be a restriction in plate heat exchanger causing overheat |
PCB Fuse blowing, House RCD tripping |
Overheat thermostat/wires can short to earth,check wiring harnesses inside combustion chamber for heat damage. Check for water ingress on or around diverter valve |
| Water leaks | Washers on plate heat exchanger go brittle and can leak intermittently Check S trap is not blocked Auto air vents can leak, check for signs of green/staining on auto air vent Heat exchanger can leak condensate from seams after a short period in operation, also check for CO/CO2 readings inside the combustion box around the base of the heat exchanger when in operation |
| H5 fault | Check the internal jumpers on the PCB are fitted correctly and not misaligned |
| Blank user display | After checking power to main PCB, suspect main PCB has gone Check user controls housing and purple wire as smallest bit of moisture can cause poor connection |
| Droning/Kettling Noise | Check S Trap and sump are clear, check condensate pipework for blockages Gas valves can also make a loud 'jubbering' noise if faulty |
| H3 | Faulty hot water sensor |
| Pumps/Diverter Valves | There are three different pumps and diverter valves on these models, make sure if you need a replacement that you order the correct ones. Diverter valves include; red top, grey top, black top Pumps include; Myson CP61, Myson CP61W(also fits WILO), Grundfos 15/60 |
Mini Combi Range C24,28,32
| Problem | Solution |
| Flow Fault | Small differential hole in primary flow switch housing can block right at the back, carefully remove small brass'pip' with a screwdriver (this does screw out), and use a small ball ended allen key to clean out the hole |
| Boiler on no demand | Water flow switch can stick, make sure the boiler is not in frost potection mode |
Response
| Problem | Solution |
| Explosive Ignition | Weak Spark from generator, check electrode gap, |
| Overheating | Water flow switch can stick, oring from the flow regulator can make switch stick on by jamming in switch |
| Blowing fuses, tripping RCD | Low water pressure switch can leak internally and cause electrical issues/blowing fuses/tripping RCD |