First thing to try is to check the flue to see if it is blocked or even partially blocked. This type of flue assembly exhausts burnt gases from the heater and another section draws fresh air in to the heater to be mixed and burnt with the gas. the centre of the flue is the exhaust section and the outer section of the flue is the fresh air intake section. removing the flue cowl will allow a visual inspection of the flue for any blockages. If the flue is a long run then a plumber may need to be called to disassemble the flue for a closer inspection.
Answers & Comments
First thing to try is to check the flue to see if it is blocked or even partially blocked. This type of flue assembly exhausts burnt gases from the heater and another section draws fresh air in to the heater to be mixed and burnt with the gas.
the centre of the flue is the exhaust section and the outer section of the flue is the fresh air intake section.
removing the flue cowl will allow a visual inspection of the flue for any blockages.
If the flue is a long run then a plumber may need to be called to disassemble the flue for a closer inspection.