E61 cooling down

hedonist222

Hi everyone

I noticed that my week old Cinquantotto cools down after pulling a shot.

It’ll turn on and get hot. The usual scorching hot.

Then a few hours later I’ll find that it’s on but the group head is warm.

Raising the lever seems to warm it again. But it’s not eco mode.

I ran some water out and it’s 65 Celsius.

I double checked that eco is off.

I even tested eco by turning it on.

It sends the machine into standby after about 90 minutes and the green light goes off.

What’s going on?

Very strange for a brand new machine.

MediumRoastSteam

hedonist222 - The only thing I can think of is a thermosyphon stall, but I was only familiar with those when the machine is cold, not when idling.

Are you 100% sure there’s no other “eco function”? Is this pattern observable consistently or sometimes it doesn’t happen?

DavecUK

hedonist222 I have not seen the inside of one, but lets make the reasonable assumption that it’s an R58 (plumbing wise) with a new coat. In a dial boiler, if any part of the thermosyphon loop is coming out of the top of vertical boiler and the water level drops…the thermosyphon will stall, and the machines group will go cold. The water in the boiler will still be the correct temp, but a warm and not hot group will chill it down again….hence the water at 65C. I guess if you run enough out it will gradually get hotter.

How Rocket tried to fix this was by putting a forward tilt on the brew boiler, this crudely allows some loss of water without the stall, just hold a drink bottle at a 20 degree angle from vertical, and you will see what I mean.

The reasons this happens:

It’s in eco mode (but you checked that)
There is a leak back from the 1 way valve on the sealed brew circuit…usually this is the first component after the rotary pump. You can often tell if you hold the pump inlet tube up from the tank, you might see the water level gradually rising in the tube if the leak is fast enough.
It’s leaking from the group (you may not always notice, but if you have a permanently damp portafilter, it’s a red flag

Double check everything then contact your retailer.

hedonist222

I think it’s #3!

Because there was always one strange symptom when it cooled down.
The portafilter was always wet. And the shower screen was damp.

My PF is always bone dry when I come to make an espresso.

Can it be coffee sensor’s flow control device?

Either the gauge or the mushroom itself?

hedonist222

@medium roast

Always happens between first shot of the day and the second.
Always after warming up, me pulling a shot. But not every time. 3 and out of 5 times.
But it never happens first thing in the morning. It’s always after pulling a shot.

Machine will turn on at 6 am and I’ll make my first espresso at 8.
At 10, it’ll have cooled down.

DavecUK

hedonist222 But it never happens first thing in the morning. It’s always after pulling a shot.

Probably because when it’s cold, the thermosyphon is full as you probably pull a shot then shut it down…so in the morning it heats up…you do the first shot and then it gradually leaks down enough to stall the thermosyphon.

hedonist222

I just checked.
Instructions say to wrap a bit of teflon on the gauge male and then thread it in.
When I pulled mine out, the teflon I wrapped around the male thread had moved or shifted or snaked upwards - so as I was threading it into the machine, the teflon was swirling upwards.
Essentially it was like I screwed the gauge in without teflon and no plastic stock O ring.

DavecUK

hedonist222 Essentially it was like I screwed the gauge in without teflon and no plastic stock O ring.

Could well be the issue, especially if it was working nomally before you fitted it. When you wrap the teflon, it must be the right way….essentially to avoid the action of screwing it in to unravel the thread.

So if you are holding the gauge, with the thread towards you, wrap the PTFE anti clockwise (hope I got that right).

hedonist222

Oh
Thanks, Dave and medium roast for always being there.

hedonist222

I get you and I did that
I mocked it by threading between my fingers
No unraveling

But it snaked upwards
I just did it again and it looks ok

Will find out tomorrow

Assuming it was the loosely threaded gauge, why would the PF be damp?