If there is a AAV on suction side of the pump close it after venting.
I had one sucking in air when pump was running.
!/4" solenoids are no problem to source should you need one.
Flue stat lives under the top casing cover.
I also have an igniter BNIB if you need...
It could be one of the solenoids coils going o/c.
If the Teddington flue stat sticks in the hot position the DAS does not recycle.
It stops the motor when it detects heat.
If you remove boiler unions and fit Bi plugs to two tappings and connect mains water to the other two you can soon test for a blockage
If the stem diameters are the same it may last.
I always have spare coils so i have never tried this as a permanent fix.
Have you checked the tappings on the boiler for blockage ..? I presumed you had.
The pumped return can suffer from "Back end rot" if return Temp...
I would be looking for a Dumball anti gravity circulation valve that is partially open.
Are you sure that your pump is doing what it should.
No there are no small waterways.
The boiler body is just a tank with 4 tappings welded on and maybe a baffle plate to diffuse the water flow.
What do you need to know.
What are you trying to change.
If just the diaphragm its a simple job needing A screwdriver and adjustable wrench.
If the whole flow manifold you...
With an adjustable spanner usually.
Which model is it ?
No problem, All the manufacturers fit them,
Is your system fully pumped.
If you really must Then link terminals 1 & 2.
Look on the Gassafe website for one
What happens if you reset it.
Does motor run or Buzz
It is time to find a decent fitter to replace "Boiler Guy" then !!
The magnetite (Dissolved steel ) can solidify and partially block the pipes usually the cold feed where it joins the flow.
When the pump first...
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