Final answer:
If an appliance cannot be installed according to regulations, it must be reported to the gas distributor or the relevant authority. Attempting to install it otherwise could lead to safety issues and is not compliant with legal standards.
Step-by-step explanation:
When an appliance cannot be installed in accordance with the regulations, it is required to report the issue to the appropriate authority, which could be the gas distributor or other relevant oversight body. Installing the appliance 'as best as possible' or leaving it 'as is' if it doesn't meet regulatory standards could result in safety hazards or legal consequences. Regulations should be strictly followed; they cannot be changed by individuals to suit a particular installation scenario, but should be adhered to for the safety and legality of the installation. Therefore, if an appliance cannot be installed as per the prescribed regulations, it is mandatory to seek a professional resolution rather than attempting an improper installation.