Ideal Classic Boiler problem

[onekevinrobinson]

I have an Ideal Classic boiler and whilst being set to be active for the whole of the 24 hour period, it stops working (generally through the night but sometimes through the day as well). What ever happens, causes a small button to pop out at the side of the boiler which has to be re-set to allow the boiler to ignite once again.

The pressure keeps falling as well which I guess is a leak in the system somewhere but as yet I haven't found it. The fault can and does occur even when the pressure is correct.

I do not have a clue why the pilot light goes out and requires the boiler to be re-set. Does anyone have any idea what the fault may be? Any help would be gratefully recieved. Thanks in advance.

[Set Square]

I don't know this particular boiler, but it sounds like the overheat thermostat tripping.

This can happen when a timer or room stat or cylinder stat turns the boiler and pump off simultaneously - and the boiler's internal temperature goes on rising due to the residual heat in the metal parts - to the extent that it overheats. It can also happen if the pump continues to run, but the hot watr cannot be carried away from the boiler because all routes are blocked.

The first thing to check is that the pump is correctly wired - such that it runs whenever the boiler needs it to run, regardless of any timer or stat settings. The second thing to check is that when the boiler stops firing but the pump is still running, the water has actually got somewhere to go to. If the CH and HW have separate zone valves which can both be closed and/or if most or all of the radiators are fitted with TRVs which can all be closed, there *must* be a by-pass circuit - preferably controlled by an automatic by-pass valve which only opens when required.

If this doesn't fit your circumstances, or if it needs further explanation, please come back with further details of your system - viz conventional or combi boiler (I'm sure some will know from the model) config of system in terms of pump, zone valve(s), hot water arrangement, TRVs etc.

[John]

The pilot light goes out because the overheat thermostat operates as evidenced by the little button popping out. When you press it back in you reset the trip mechanism. Your losing pressure is the most likely cause of the problem as loss of pressure allows ingress of air into the system and more than likely this creates an airlock which stops circulation of the water in the system. There is a secondary possibility that the actual boiler control thermostat is failing but this is far less likely than scenario 1 above. Find and fix the leak causing the loss of pressure and the problem will probably go away The Classic is a very reliable and well engineered boiler which with a little running maintenance, will probably outlast by about two lifetimes some of the units being launched on the market at present

[Ed Sirett]

The button is due to over-heating. (Lack of flow, lack of over-run pumping, thermostat out of calibration, over-heat sensor likewise).

See the SealedCH FAQ below for the complete run down on pressure loss etc.