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ARW ARW is offline
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Default Filling up gravity central heating

On 06/10/2019 17:09, Andrew wrote:
On 06/10/2019 16:19, ARW wrote:
On 06/10/2019 16:12, Andrew wrote:
On 06/10/2019 15:06, newshound wrote:
On 06/10/2019 13:00, ARW wrote:
The water to the header tank was turned off and the system drained
down.

Swapped the mid position vale and it will now not fill back up.

The odd thing is the header tank did not drain off - it was still
full when I went to turn the water on.


Suggestions?

--

Adam

Airlock.

No CH when I was a kid, but a routine at home every time a hot water
tap washer had to be changed was to connect a hose between hot and
cold water taps in the bathroom, and turn both on.

+1,

except that both those taps would be fed from the same tank so
should have equal pressure.

Connecting the kitchen cold tap fed from incoming mains to
a hot tap would be more like it.


The HW tank is not relevant is it?

I never touched it.






In that case try connecting a hosepipe to the C/H drain cock,
and see if that pushes water up into the C/H header tank ?.

You might have to manually move the 3W valve to the heating
position.


I did. We filled the CH circuit up that way and eventually it started
adding more water to the already full CH header tank via the expansion pipe.

I now realise the logical conclusion at this point would have been to
block the expansion pipe and try to fill the header tank via it's feed
pipe (ie the 15mm gravity feed pipe that the tank uses to feed the CH
pipework from) or in other words (Star Trek and Scotty anyone, just
reverse the gravity laddie) to prove that this pipe was blocked.

Cheers for the help. Much appreciated.


--
Adam