air block?

the easiest and quickiest way is to attach a hose from the cold water pipe on to a hot water tap and the high water presssure will push the air lock out it may be dirt from the tank but this method will clear both. just beware that putint the water in will fill the plastic header tank and if u hold the cold water pipe on to long it will send water out the overflow pipe. another way is if u have a mixer tap is to put your hand over the spout then open the hot water fully keeping your hand over the spout then slowly open the cold until u can hold the pressure and this inturn will force the cold water into the hot water pipe pushing out the airlock hold it there for 10secs or so gl

kash
November 2012