Would appreciate Info on Suprima 80 Problem. Boiler has been running is short cycles. Running for 90 seconds, stopping and immediately returning to to starting cycle, igniting and running for about 90 seconds and so on. The result is that it was taking a very long time to gain heat. Icould hear the Air Pressure Switch activating prior to the boiler returning to stand- by I changed the switch. This had the effect of making the boiler run for longer and gaining more heat but still in short bursts possibly because the new switch had a stronger diaphragm. I have changed the Heat stat and thermistor and switched the PCB with a good one. It made no difference. Can anybody help please. Also I am interested in the function of the red hose on the air pressure switch. Why is it positioned where it is ? What does it do. Any help much appreciated.