Rocket Evo - possible issue / plumbed in
Have had my Rocket Evoluzione V2 for about 5 years, plumbed in via pressure reducer / filter.
Went to use it earlier - to drain some boiling water off - pump started up to fill the boiler as normal, but didn't shut off. Oops - I assumed it could have been a fault with the water level probe and to find a puddle under the machine , but the boiler wasn't filling. Turned off and back on, then actuated the lever, the pump kicked in as normal, but there was only a very low flow - dribble - out of the group head. Recheck with blind filter - and no pressure. Checked water line - and there's good/normal flow - no evidence of air. Filled the tank - and switched over to tank supply, turned it on, the pump kicked in as normal - was actually filling the boiler normally. Open lever with blind filter, and it cranked up to full pressure normally. Hmmm - switch it back to mains water supply - and it's working perfectly. It would be very nice to think that I fixed it without doing anything - but unlikely IMO - more likely a fault which may recur. Seems a bit odd to me - at first I thought it could have been a problem with the pump or water supply - but I don't think so. I assume there's a 2 or 3 way solenoid valve between pump and Hx/boiler fill. Is it likely that this is getting sticky or there's a control circuit issue? Any other possibilities?
Have you descaled recently? Could it be a piece of scale got stuck somewhere like the 3 way valve etc?
I did strip the machine down last year - replaced the seals etc in the group head and replaced the element which had blown. It was all very clean - no scale on the group I could see, a trace of scuddy stuff on the bottom of the boiler which I cleaned out, a few small spots of scale on the dead element. Relatively soft water here, about 40g/m3 as CaCo3, the water is filtered, filter isn't very old but hasn't been replaced lately either, so I doubt it was something blocking the line.
The machine seems to be working fine now. I'm wondering if it was a false alarm - there is some building work going on nearby, the toby valve to our place isn't clearly marked, perhaps a worker turned off our water supply by mistake for a minute or two - that's happened before. Trickle when I opened the lever may have just been what was left in the Hx circuit dropping out.
With the rockets I have there is a solenoid adjacent to the pump (it is not the opvalve). It's function is to control the direction of the water exiting the pump to either to fill the boiler or to feed the extraction. I had a fault so that on an extraction the water also filled the boiler - I mean filled it. My service folk were able to dismantle the solenoid, clean the water flow areas of it and reassemble. This has fixed it. Still good 2 years later.
Most rockets have similar internal plumbing so a parts diagram will show approximately where this solenoid is. Now your fiddling have have cleared it.
I think it is called the Boiler Fill Solenoid on the parts diagram.