Isolate Mains Power to appliance as per TOPs P4
Disconnect condensate trap

Observation:

Inspect condensate trap and drain for blockage.
Note:
1. There will be condensate in the trap bottle in normal use. The trap should be primed when refitted i.e. trap part filled with water.
2. Before reassembly check the integrity of all disturbed gaskets and seals and replace as necessary.