HIGH residue levels in gas supplies, which caused 150 boilers to shut down late last year, have recurred and have affected 20 homes so far.

Guernsey Gas has advised customers who find their boiler has shut down without reason to contact its 24-hour emergency helpline on 749000.

Customer and network services director Robert Gardner said steps were being taken to source alternate supplies and reduce the risk of further problems resulting from high residue build-up, or ‘heavy ends’, in the future.

‘It is important to stress that there are absolutely no safety concerns and it is simply a case of replacing a boiler part, which is being done at no cost to the customer,’ he said.