Worcester Highflow 400 RSF Installation And Servicing Instructions page 28

Fig. 27. Flue Option 6. Extension flue upwards and horizontal using a second 90° flue bend.
The two flue lengths, when added
together, must not exceed 2300mm
B 210mm minimum
Fig. 28. Flue Option 7. Extension flue horizontal using a second and third 90° flue bend.
The three lengths, when added
together, must not exceed 1000mm,
Appliance
Second 90¡ flue bend
Air duct = (B Ð 166) mm
Flue duct = (B Ð 152) mm
First 90¡
flue bend
Air duct = (B - 166) mm
Flue duct = (B - 152) mm
Outside
wall
Air duct = (C Ð 58) mm
Flue duct = (C Ð 14) mm
Appliance
Third 90¡
flue bend
Air duct = (B - 166) mm
Flue duct = (B - 152) mm
Second 90¡
flue bend
28
First 90¡ flue bend
C
Outside wall
Air duct = (C - 58) mm
Flue duct = (C - 14) mm