Just a simple curiosity question about my espresso machine, a Pavoni. Why do some machines (older ones) have two power switches? I know one is just for power and the other is for the heater, but why two? Just different wattages? Do they serve any other purpose? I've thought about this before, but what brings me to ask today is that I thought I hit both switches this morning but found out a long hour later that I had only turned on one... what a long, long wait for my morning espresso

Assuming you don't have a dual boiler machine with a separately controlled steam boiler, a lot of commercial machines have the pump/autofill/etc. separately switched from the heating element. Some machines may even have the heating element controlled in two separate wattage stages.

Some of the Pavoni's had two switches or a two position switch for low and high heat. High heat being for milk steaming and low intended for espresso use.

Check out the http://www.pavoniexpress.com site for more details.

p.s. mea culpa, too early in the morning to be posting advice on a machine I don't have.

I have the Pub V1 and Pub V2 models. It's the V2 that has two switches. It's not high/low, it's on or off, and this morning, even though the main power was on, the heaters were off. Rough way to start the morning

I've worked on a few commercial espresso machines that have two-position power switches. The first position powers the pump, the second powers everything, including the heating element. The first position is handy when you flush/refill the boiler since the pump has power but the heating element doesn't.

The manual specifically identifies them as the main power switch and heating switch. The first one probably supplies power to everything other than the heating element(s), and the second one enables the heating element(s).

Thanks guys. I know what the two switches do, I just want to know WHY? HB is probably on track, but I just haven't found myself in the position to just flush/pump. In a commercial setup (which, of course, is how these machines were designed), is it common to only flush/pump (without pulling a shot)? I don't know, it just seems redundant...especially when you want that morning shot. Again, this is just simple curiosity, nothing earth shaking.

Why? To elaborate on my prior post, it's common to flush the boiler several times when descaling. Turning off the heating element while allowing the pump to run means you can refill the boiler without worry that the heating element will melt. A two-position switch is common for commercial equipment, but not unheard of on semi-commercial espresso machines. For example, the Vibiemme Domobar Super has one.

Is actually like
so
normally
position ONE will be everything BUT the Heating element
position TWO the line to the (pressurestat) heating element
on pavoni commercial machines (and other for this matter)
there are 2 different switches that do like above

I installed a switch to cut the power to the PID in the back of its project box housing so I could do a better job descaling. This prevents the heating signal from being sent to the SSR but keeps power to the pump so you can flush cool water through.



Rather than diluting the descale solution to imperceptible levels with dozens of cycles, I can do a complete drain and then refill. In practice it still takes several cycles, but quite a bit fewer than if you could only flush enough to keep coils submerged. This might not be an issue for the heat exchanger because it may flow right through in a First-in-First-out fashion that rinses clean quickly (and the coils will never be exposed).