Abstract: A fluid fuel consuming apparatus (such as a gas fire) is disposed in a room of a building and a supply of fluid fuel is connected to the apparatus via a valve unit (10) disposed in the same room. The valve unit comprises a valve member (18) movable between a closed position blocking a fuel pathway between its inlet and outlet ports (48I,48O) and an open position opening the fuel pathway A gas detector (42C,42H) is mounted in the valve unit for detecting the presence of a particular gas (such as carbon monoxide) and/or group of gases (such as hydrocarbons) in the atmosphere around the valve unit. The valve member, if in the open position, is automatically moved from its open to its closed position in response to the detection of the presence of such gas.

Abstract: A frost protection system is described for a condensate drain pipe for a boiler, air-conditioning unit etc to protect an outdoors run of the pipe. The system comprises an outdoors temperature sensor, a heater, and a controller for activating the heater in dependence upon the temperature sensed by the sensor. The heater is in the form of a flexible line (for example an electrical cable with a resistive filament). The heater (or a connection for it) passes through a fitting in the pipe indoors, and the heater extends along the inside of the outdoors run of the pipe. In cold weather, the controller activates the heater to produce heat inside the drain pipe and thus reduce the risk of the condensate freezing.