Thank you for your help .. I am pretty set on outboarding the delay relay .. but I am also outboarding the motor pump and I am running into some discrepancies between what I see in my machine and the hydraulic diagram in the manual , so I am trying to make sure that A, I dont make any mistakes , B , ensure that my machine is not missing any parts modified by the previous owner .

- In addition tot he pre infusion feature made available by the delay on make relay , another feature told by others who added that relay is that the refill solenoid would work without the pump/motor being switched , and since refilling doesnt need the 8-9 bar pressure , the water mains pressure 1-1.5 bars is sufficient ... that will mean quiter refills .. which is an added plus . Is that true ? Common ?
- OK would that mean that the line feeding the refill valve .. carries only water mains pressure ( Before the pump raises the pressure ) ? BUt if so , then I am not clear as to how that happens ... most machines have the pump on board , feeding pretty much everything ...does that mean water is carried throughout all lines at water mains pressure , and ONLY when the pump is engaged doest it push the pressure to the 8 bars, other wise water stays at the lower pressure ? " My machine now ( not the project ) engages the pump automatically every time the auto refills calls for a refill " ..
- I guess I am not sure how then , the delay relay would affect the auto refill solenoid .. I get the brew pressure being held for whatever delayed time .. but it is the auto refill I dont get .

SORRY IN ADVANCE IF THE ANSWER IS SO SIMPLE AND I DIDNT SEE IT !!!

maxwerks wrote:Thank you for your help .. I am pretty set on outboarding the delay relay .. but I am also outboarding the motor pump and I am running into some discrepancies between what I see in my machine and the hydraulic diagram in the manual , so I am trying to make sure that A, I dont make any mistakes , B , ensure that my machine is not missing any parts modified by the previous owner .

Normally, as far as the pump is concerned anyway, it is very easy to see the pump intake pipe and the outlet pipe, and you'll have to disconnect these anyway. Provided you connect your outboarded pump to the same points it should work like the internal pump you are replacing. The new fittings you will need to connect inside the machine will be female screw fittings to replicate those on the pump. They will be either taper thread or gas type threads, depending on the particular pump, and you'll need the corresponding male connectors at the other end of the new pipe to connect to your pump. That would be by far the easiest way to do it without having to worry about exactly how the rest of the hydraulic system is designed. As for mods made by a previous owner, that's anyone's guess, but if the machine currently works, things should be OK anyway.

maxwerks wrote: - In addition tot he pre infusion feature made available by the delay on make relay , another feature told by others who added that relay is that the refill solenoid would work without the pump/motor being switched , and since refilling doesnt need the 8-9 bar pressure , the water mains pressure 1-1.5 bars is sufficient ... that will mean quiter refills .. which is an added plus . Is that true ? Common ?

Certainly in my case it will refill without any pump pressure - but only for the few seconds the delay relay adds, as the circuit powering the pump still goes through the new relay, so the pump starts up after that time has elapsed. You do need enough pressure to overcome whatever pressure is in the boiler at the point the machine refills. If you only have 1 bar line pressure, it probably won't work as a steam boiler is likely to be over ~1.2. Mine currently has a static line pressure of 4 bar, but I may play around with that a bit to see what works best for the pre-infusion.

maxwerks wrote:- OK would that mean that the line feeding the refill valve .. carries only water mains pressure ( Before the pump raises the pressure ) ? BUt if so , then I am not clear as to how that happens ... most machines have the pump on board , feeding pretty much everything ...does that mean water is carried throughout all lines at water mains pressure , and ONLY when the pump is engaged doest it push the pressure to the 8 bars, other wise water stays at the lower pressure ? " My machine now ( not the project ) engages the pump automatically every time the auto refills calls for a refill " ..

Yes. My machine is a double boiler machine, so the brew boiler is always full. It is the steam boiler which calls for refill when needed. In the case of this machine, the water for the steam boiler comes from the brew boiler, so the process is that a solenoid valve opens between the two boilers, and the pump engages at the same time. The fresh incoming water is pumped into the coffee boiler and the pressure then pushes water out through the opened connecting valve into the steam boiler. Provided the incoming pressure is higher than that in the steam boiler, this will happen without the pump running. As there is a backflow preventer valve it is pretty safe even against mains water pressure failure. It would not work without line pressure, e.g. for those folk who run machines from a tank, but then you wouldn't be making this sort of modification in the first place.

maxwerks wrote:I guess I am not sure how then , the delay relay would affect the auto refill solenoid .. I get the brew pressure being held for whatever delayed time .. but it is the auto refill I dont get .

SORRY IN ADVANCE IF THE ANSWER IS SO SIMPLE AND I DIDNT SEE IT !!!

See comments earlier. Your delay relay is effectively an inline switch before your pump. So, every time your pump is activated by the machine, it will go through that same delay process including when the boiler fills. This is unless you have a machine with a separate power feed to the pump just for refill purposes, which sounds unlikely. If the fill solenoid and the pump are normally activated by your control box at the same time, then the solenoid will still open straight away, but the pump will have its delay.

If you do go ahead and outboard the pump. I'll be interested to know how you get on - it might inspire me to get on with it

I have a LM 3gr EE and Just out of curiosity... what if you add a manual switch to power a relay in a new circuit that activates the solenoid only... which could be a toggle or a timer then manually active normal brew group.. there could possibly be a 3 way switch... of course one is off.. the other 2 are on activate solenoid, then pump and solenoid ... it seems to make sense but I haven't drawn up any wiring.. ut this way each group would have its own way to slightly pressure profile ... I'm kinda of brainstorming and haven't really looked at the circuits but did work on them a few years ago.. it seems possible...