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I couldn't get anything pushed through the coil - the combination of the right angle at the start and the friction of the side of the coil means I couldn't get anything in more than about 50cm.
So I connectedted a bypass between the feed and return pipes cutting out the coil and ran the system. Hot water then went right though so the rest of the path is clear and the pump is OK (low speed). So the coil IS blocked - probably sludge.
Any ideas on what I can do or is it a new tank?
**************************** I have an oil fired boiler system with two circuits, both pumped. One drives the rads - which works fine, the other goes to the hot tank. Since September I've had no hot water from the tank. I fitted a new pump but no joy. What happens is this:When the boiler has been running for a while the feed to the coil gets hot as expected but no matter how long the boiler runs, all day even, the return is always cold. If I switch off the pump I can hear the water "falling" back down almost like the pump has been pushing against a blockage.
So I drained the system and disconnected both ends of the coil and there is standing water at both ends. I would have assumed that the coil would have drained out via the bottom pipe when I emptied the system, is this correct?
Does this all seem like the coil is blocked inside the tank. If so can it be unblocked or is it time for a new tank.
House was built in 1995
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