We have a Greenstar HE System that has been staying on even though its turned off at the slide off control,it shows fault code P1 P2,I've checked up and it says that the 24 V fuse has blown and needs replacing, my question is what, and where is the 24 V fuse? thanks for your time....

Dafydd Griffiths, December 2016

Fuses are rated by current - sure enough the manual says replace the 24V Fuse but it neglects to say the current rating.

There are 3 fuses on the circuit board - 2.5A / 1.6A / 0.5A and there'll be an external 3A fuse as well. The manual here...

https://letsfixit.co.uk/wp-content/uploads/ZB-7-27-HE-SYSTEM.pdf

Says...

Fuses
B Remove the connections covers. Refer to fig. 27,
28.
The fuses are located adjacent to the mains connector
block and connector ST18. Refer to fig. 4.
Fuse, item 312, is only replaceable by removing the
pcb.
Spare fuses are fixed to the connections cover.
A fuse pack is available: Part number 8 744 503 010 0.

Good Luck..., December 2016