Ferrolli Modena 80E

[DP]

Couple of questions for those that are sh**e hot with Ferrolli boilers.

For hot water demand, the fan run is delayed by anything from 2 seconds to 16. It could be more but this is the spread I got when I was testing the boiler. 240 (in fact 230) volts is applied to the fan as soon as the green demand light comes on. This voltage is seen at the neutral terminal as well (indicating lack of neutral condition). When the neutral condition appears, fan starts to spin. APS is testing OK. Safety stat also tests OK.

Second defect is to do with temperature swings during HW. At lower HW stat setting, mod voltage is 26 volts, and the water from the tap is warm (not hot). It would have to be hotter for the shower. At this low stat setting, temperature is stable.
At higher setting, water gets hotter but then the burner shuts down cooling water at the tap. The temperature swings between useable hot and cold.

Your views on above malfunction would be greatly appreciated.

 

[cross thread]

main fault with modena is thermistor related swap both as the pcb reads of both

 

[DP]

Them babies have been replaced.

 

[ollski]

Them babies have been replaced.

Recently Danny?, mind you if its struggling to sense the initial demand and dropping out on hot water what are you getting from the flow switch? (aqua-sensor)

 

[DP]

Thermistors were changed last week.

Low setting on HW stat produces stable hot (to be more precise warm) water. Temperature fluctuates at higher setting.

Have spoken to Ferrolli who say the boiler funtions correctly/ could be faulty pcb/ negative switching could be faulty. Nothing precise.