I have a used Del-1 and it works decently but the pressure drops whenever I pull a shot and the machine begins to make a lot of noise. It has been getting worse. The reservoir is full and it has good water pressure to the machine. When not in use the pressure rests at 3 bar and I have read that while brewing it should register 9 bar. However mine only reaches 6 bar and decreases from there. Can anyone identify the problem

Ben

I think I have figured it out. There was hardly any water pressure to the machine. It used the water in the line and when that was done it only had a trickle to feed the machine. I have been reading other posts and there is some debate about running the machine from a bucket of water. Is it okay to do this temporarily or should I just shut it down for a few days? This machine has a rotary pump, I am not sure it that affects things or not.

Ben

The noise you heard was probably the pump cavitating due to lack of supply-side water debit. As you can read in threads like Can a rotary pump suck up from a bucket?, not everyone agrees it's wise to run without positive pressure. For what it's worth, I noted that the La Marzoccos at past SCAA barista competitions were run from water jug / check valve setups.

Most rotary pumps in good condition are rated for at least 5 foot of lift on the inlet side without pressure, but you have to make sure that the pump stays primed, a one way valve with a flow rate that matches your inlet is called for. The condition of your vanes in the pump may limit the lift you can get if they are old and hardened. You have to remember most rotary pumps are WAY short of their ratings when used in a espresso machine.

For reference I used mine on a bucket feed for several months, with no problems. I got tired of filling the bucket and went to a flojet + accumulator setup off a standard 5 gallon bottle. Call it a cart style install.

Having the drain plumed in or to a large dump is one of the best changes in your work flow.

Good luck!

-Cecil