Filling Device for a Pressurized Heating Circuit

Abstract

A filling loop device is provided to facilitate filling of an installed pressurised heating circuit ( 2 ) including a boiler (furnace) ( 1 ) from a mains supply pipe ( 3 ). The device includes a dead-man valve ( 14 ) configured to normally close off a water channel provided by a hose ( 16 ). This ensures that the channel can only be opened when attended during charging. Conventionally the hose ordinarily used to charge the heating circuit should be removed after isolation valves are closed at the inlet ( 4 ) and outlet ( 6 ). However careless operatives have been found to have frequently left the hose in place with the isolation valves open causing serious damage to the boiler. A second embodiment of the invention includes a pressure regulation valve ( 25 ) in the filling loop device to prevent careless operatives charging the system to excessive pressure. A third embodiment provides a pressure regulation valve in the circuit, normally biased to a closed condition with a dead-man actuator to open the channel.

1 . A filling loop device for a pressurized heating system comprising:
 means defining a fluid passage having, an inlet port connectable to a fluid supply and an outlet port connectable to a heating system fluid circuit; and   a dead man valve interposed in the passage between the inlet port and the outlet port, said dead man valve biased to a normally closed condition to shut off fluid flow through the channel in either direction when unattended, and manually operable to an open condition to permit fluid to flow from the inlet port to the outlet port;   a casing ( 14   a ) having; a fluid passage ( 14   b ) with an inlet port and an outlet port and, a spool chamber ( 14   e );   a spool ( 14   f ) slidably housed in the spool chamber ( 14   e ), said spool including a through passage ( 14   g ) capable of communicating the inlet port and outlet port for fluid flow therebetween, and   bias means to urge the spool so that a lower part of the spool obstructs the passage, and   a drain passage ( 14   k ) formed in the lower part of the spool ( 14   f ) and communicable between the outlet port and a drain port ( 14   j ) formed in the lower part of the spool chamber ( 14   e ).   
     
     
         2 . A device according to  claim 1  comprising a pressure regulator valve ( 25 ) pre-set to prevent excess pressurisation of a heating system. 
     
     
         3 . A device according to  claim 1  or  claim 2  wherein the bias means comprises a spring ( 14   e ) to spring bias the spool to close a fluid passage through the valve and a manual actuator operable to displace the spool in opposition to the spring force while manually attended. 
     
     
         4 . A device according to  claim 3  wherein the actuator comprises a press button ( 15 ). 
     
     
         5 . A device according to any of  claims 1 - 4  wherein the drain port ( 14   k ) is formed in a base of the spool chamber  14   e.    
     
     
         6 . A device according to any one of  claims 1 - 5  wherein the drain port ( 14   k ) is provided with a hose coupling. 
     
     
         7 . A device according to  claim 6  wherein the hose coupling is a nipple ( 14   o ). 
     
     
         8 . A device according to any preceding claim wherein the drain passage ( 14   k ) is isolated from the through passage ( 14   g ). 
     
     
         9 . A filling loop device for a pressurized heating system comprising:
 means defining a fluid passage having, an inlet port ( 31 ) connectable to a fluid supply and an outlet port ( 32 ) connectable to a heating system fluid circuit; and   a dead man valve interposed in the passage between the inlet port and the outlet port, said dead man valve biased to a normally closed condition to shut off fluid flow through the channel in either direction when unattended, and manually operable to an open condition to permit fluid to flow from the inlet port ( 31 ) to the outlet port ( 32 );   wherein said deadman valve is provided by a pressure regulator valve ( 30 ) pre-set to prevent excess pressurisation of a heating system;   said pressure regulator valve having means biased to normally close a fluid passage ( 38 ) through the regulator valve and an actuator ( 34 ) manually operable against the bias to open the fluid passage.   
     
     
         10 . A device according to  claim 9  wherein the regulator valve comprises a displaceably mounted piston valve seat spring biased to close a fluid passage formed between the piston valve seat and a poppet valve ( 39 ). 
     
     
         11 . A device according to  claim 9  or  claim 10  comprising a cam ( 43 ) rotatable from a closed condition to an open condition, where in the open condition the cam acts against the piston valve seat ( 38 ) to open the fluid passage between the poppet valve and the piston valve seat ( 38 ). 
     
     
         12 . A device according to  claim 11  wherein the rotary axis of the cam ( 43 ) is offset such that the spring force always displaces the cam towards the closed condition. 
     
     
         13 . A device according to  claim 9  or  10  comprising a shaft ( 44 ) sealingly journaled through a casing of the dead-man regulator valve to couple with a manual actuator provided by a knob ( 34 ). 
     
     
         14 . A boiler in combination with a filling loop device according to any one of the preceding claims. 
     
     
         15 . A method of charging a pressurized boiler and heating circuit comprising the steps of:
 providing a fluid channel between a mains water supply and the pressurized heating circuit, said fluid channel including a dead-man shut off valve having a manually operable actuator configured to close the channel when not manually actuated;   manually actuating the dead-man valve to allow water to flow from the mains supply to the heating circuit until the heating circuit reaches a specified operating pressure;   releasing the dead-man valve actuator to shut off the channel.   
     
     
         16 . A method according to  claim 15  comprising leaving the fluid channel in place after charging the pressurized boiler and heating circuit. 
     
     
         17 . A method according to one of  claim 15  or  16  comprising providing a one way check valve in the channel to prevent backflow from the heating circuit to the mains supply. 
     
     
         18 . A method according to any one of  claims 15  to  17  comprising providing a pressure regulation valve in the channel pre-set to regulate the maximum pressure of water deliverable to the heating circuit in order to prevent charging the heating circuit to a damaging excessive pressure.