Biasi 24S Problem

[newcomers]

ill go back tomorrow and check voltage again at the gas valve and then report back

 

[newcomers]

also forgot to mention that it did modulate when getting hot (getting lower) but then would only rise to 6mb

 

[Agile]

hi guys,

went to a job just now, complaint was hot water not hot enough.

Got there, opened hot tap, and it was running warm, and only got hot when I slowed the flow rate.

I checked the burner pressure and it was only 6, and it sholudve been 10.

I removed 1 of the wires from the modulating coil from the gas valve, switched power back on and min pressure was ok.

Put the wire back on, and then the pressure wouodnt go above minimum, and now wont do so. I removed both wires from coil and measured the resistance across the wires and got OL, and when I measured the resistance across the coil the resitance was very high.

Basically, I dont know whether its the ignition board or the gas valve thats faulty. What do you guys think?

Thanks

Mod coil is about 280 ohms but that never fails!

First check in inlet gas pressure in case thats too low.

If its stuck on 6 mB ignition setting burner thats because ignition PCB has failed to signal the main PCB that a flame is established. If you suspect that then vary it on the ignition pressure setting to confirm.

I dont know why you go there and find 6 mB only to leave it without checking the inlet pressure and readjusting the gas valve?

Tony

 

[newcomers]

inlet pressure was fine

 

[newcomers]

doesnt it work like the linea then, that if the ignition board doesnt tell the main board that it has sensed the flame, it goes to lockout?

What controls modulation on this boiler, ignition board or main board?

 

[Agile]

When the flame is established contacts are made in the ignition unit which cause the main PCB to switch between the ignition burner pressure and the modulating pressure as required.

The lock out occurs within the ignition PCB when a flame detection is not achieved within a few seconds.

The Linea works along similar lines.

Tony