Problem 2: pump trying to refill boiler, boiler then running out of water/steam and heater+pump shutting down.
(sorry if this rather long winded)
Now that ive sorted out any visible leaks, the unit doesnt want to keep the boiler full for steam and hot water.
I power it up and the heater and pump start - with the pump staying on for a considerable period of time. I open the steam and hot water valves to vent any air in that system, and pull on the safety valve to allow any air to escape from the boiler.
I can hear water flowing thru a valve somewhere at this point.
After a few minutes, ill start to get some pressure showing on the gauge but the pump is still noisily chugging away with what sounds like little success. Eventually, ill get just over 1bar on the gauge and the heater will start to turn on/off - this is the pressurestat working as designed.
If i turn on the group to pull a blank shot, the pump turns on and when i turn the switch off, a small amount of water comes out the back-wash tube (name?) - this makes sense.
If i try to pull a shot with the blind filter, nothing comes out the tube and eventually, i get a small leak of steam/water at the group seal and a bit more water out the tube when i turn off the pump.
I can do these two things for as long as I like without loosing water supply to the head.
But, after pulling water thru the steam and/or hot water valves, the pressure starts to drop on the gauge, and even tho the pump is now going again it seems to run out of fluid and both the pump and heater eventually turn off suggesting the tank is now low in water but high in temperature?
Im now working my way thru the various bits of plumbing from water supply to boiler looking/inspecting for blockages.
Ive found some small bits of plumbers tape inside but of most concern is the pump.
I can easily rotate it (a good thing) but there seems to be very little suction on the inlet side and if i block off the outlet with my thumb, very little pressure builds up behind it.
The anti-vacuum valve inside the pump works as designed - tho i havnt yet worked out if its sealing between the inlet/outlet.
My experience with vane pumps is only with big vacuum pumps as found in diary/milking equipment but i figured that these are positive displacement pumps so you should get pressure building up in the outlet with some hand rotation of the pump?
... or maybe im not priming the boiler correctly?
anyway, any advice on pump behaviour when hand cranks would be most welcome.