On 5 Feb, 22:45, John Rumm wrote:
Chade wrote:
On 5 Feb, 02:43, John Rumm wrote:
Chade wrote:
On 3 Feb, 19:09, "John" wrote:
"Chade" wrote in message
I've checked that the tap on the filling loop is closed.
What might it be?
Where is the needle when the boiler is cold?
Although we've not been using it, obviously, the needle has now
dropped back to nearly zero.
Top it up to 1 bar again, and see what happens when you leave it for a
couple of hours (unused).

After a couple of hours it seems to be staying at 1 Bar.

If you fire it up and watch the pressure gauge, what does it do?

Rapidly increases by just under a third of a Bar then stops, falling
back to the starting pressure when the pump cuts out.

The pressure seems to have stabilised now, no-longer dropping over
time.

A rapid
rise to higher than normal (i.e. 3 bar) would indicate your expansion
chamber has lost its air charge. If you can find the charge valve for it
(it will look like a car type inflation valve (for that is indeed what
it is)), a quick press on the centre pin should yield a puff of air. No
air would indicate a discharged vessel in need of pumping up. Water
would indicate a ruptured diaphragm inside it, meaning it needs
replacing or, more likely, another one adding to the system elsewhere.
(allowing some air into a rad may function as expansion space for a
stopgap to get the heat back on)


Should I still do this test even though it seems to be working
normally?