Apollo Fanfare Thermostats

[DavidJW]

Can any one tell me what the operating temperatures are for the HI and LO settings on my Apollo Fanfare Boiler? I don't have the user instructions and the Installation Instructions on Partsarena don't have any info.

Also, How long should the pump run for after the boiler cuts out and what should the flow temperature drop to?

TIA

 

[weareleeds]

Low stat is 140 deg high stat is 180 deg nout sure about other 2 questions

 

[cross thread]

pump over run works on air temp inside case so no set time

 

[DavidJW]

Thanks for the information

pump over run works on air temp inside case so no set time

That's interesting. I wouldn't have thought of that.

I can understand the reason for having the pump running on after the boiler cuts out, but it seems an inefficient way of cooling the boiler down.

In a boiler without overrun the boiler cools naturally as the heat in the water is extracted by the radiators. As soon as the water temperature drops to the boiler's "turn on" point (say 10 deg C drop) the boiler reignites (assuming heat is called for).

In an overrun situation the water is forcibly called by being pumped round the circuit. But if the pump runs until the air temp has dropped this would imply that the water temp has dropped even further (say 20-30 deg C). So the boiler thermostat would have cut in before the air temp reached its pump turn-off point. In which case whats the point of overrun?

Also pump overrun does not just cool down the boiler, it cools down the whole system rads and all, so the boiler has to do more work to heat up the water. Efficient??

There is probably a logical explanation for all this; but I can't see one!!