External power and all fuel pumps needed have been switched on, and the fuel tanks are all full, but the APU just doesn't work when the APU switch is on the start position. I wonder whether it is a bug or just because of my mistake.

I also had this problem, I found out that a long press on start will start the APU, the moment the needle start to move i released the start, wonder if it a bug or a real life operation.

How to start the APU

I have been having this issue where you need to hold it for far longer than 2 seconds for it to start

I also had this problem for quite some time, but holding the APU switch in the START position for 2-3 seconds works for me now.

https://www.youtube.com/watch?v=5QmMNmgyhus&t=30s

I notoced a bug eith APU. It does not use fuel during. I stood at the gate during 10 minutes with APU on and 5 tons of fuel and it did not reduce. The same digits all the time.

Alexiyi wrote on Jul 11^th, 2021 at 5:21pm:

I notoced a bug eith APU. It does not use fuel during. I stood at the gate during 10 minutes with APU on and 5 tons of fuel and it did not reduce. The same digits all the time.

While in 1007 APU now uses fuel, it doesn't take fuel from "left fuel manifold" when AC pumps are on, according to FCOM v2,12.20- APU fuel feed.

In FCOMv1 NP.21, there is a Note: If fuel is loaded in the center tank, position the left center tank fuel pump switch ON to prevent a fuel imbalance before takeoff. However in 1007, even if I only turned the left center tank pump on, APU still only use fuel from left main tank.

In some case, we also use right main tank pump via crossfeed to feed APU, this also could not be done in CS's 733.

v.1008