gas water-heater tank [2]
				 
					
					
					
						gas cock 
						Mechanism cutting off the gas supply when the water reaches the desired temperature.
				  	
 
					
						pressure-relief valve 
						Device for lowering the pressure inside the tank by releasing excess hot water.
				  	
 
					
						overflow pipe 
						Pipe through which water escapes when maximum pressure is exceeded.
				  	
 
					
					
						control box 
						Box containing the set of controls that measure temperature and operate the burner.
				  	
 
					
						drain valve 
						Device for emptying the water from the tank.
						
				  	 
					
						outer jacket 
						Metal casing protecting the tank.
				  	
 
					
						hot-water outlet 
						Outlet pipe for hot water flowing into the hot-water circuit.
						
				  	 
					
						flue hat 
						Device reducing the amount of air withdrawn by convection.
				  	
 
					
						temperature control 
						Device for setting the temperature.
				  	
 
					
						flue 
						Channel through which combustion gases are evacuated.
				  	
 
					
						thermostat 
						Mechanism controlled by fluctuations in temperature; it can be set to automatically switch the burner on or off.
				  	
 
					
						cold-water supply line 
						Inlet pipe for cold water to the tank.
						
				  	 
					
						gas burner 
						Combustion device for an air-gas mixture.
				  	
 
					
						glass-lined tank 
						Insulated reservoir protected against corrosion by an enamel or glaze coating.
				  	
 
					
						insulation 
						Material placed between the tank and the outer walls of the hot-water tank in order to reduce heat loss.