Is it worth draining boilers if the machine wont be used for 2 weeks?

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#1: Post by Wattbe » Oct 08, 2019, 5:45 am

Hi everyone,

I appreciate that this has been asked before but the answers seem contradictory and most of the posts are quite old now so hoping for some more up to date wisdom!

I won't be using my GS/3 (non plumbed) for 2 weeks and have thought about draining the boilers before leaving it.
I'd rather not as it'll save me bleeding the brew boiler when I get back (for some reason, I seem to get a small leak from the copper crush washer beneath the bleed screw which requires me to install a new one. Doesn't always happen but I've gone through a few over the last couple of years)

I'm trying to work out why it'd be beneficial to drain the boilers.
I've read that mould can form if not being used but the brew boiler is saturated so no chance of mould there. If I drained it however, there would still be a smallish amount of water left in the boiler and a lot of air which could invite mould to take up residence, so it doesn't make sense on that front.

Leaks? I can't see why there's more chance of a leak with the machine off for a couple of weeks. I turn it off at night and for the days when I know it'll not be used with no leaks. Am I missing something?

My preferred option would be to leave as is but flush fresh water through the boilers once I'm back.

I'd be interested to know your thoughts.

All the best,


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Randy G.

#2: Post by Randy G. » Oct 08, 2019, 12:39 pm

To quell any paranoia, disconnect the heating element leads and pump a bottle of cheap Vodka into both boilers. That will take care of any worries of biological growths as well as protect from freezing. You will also have a nice drink ready while getting it back into service. :lol:
Espresso! My Espresso!

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#3: Post by GC7 » Oct 08, 2019, 1:21 pm

I just returned from 2 weeks in France. Here is what I did with my QM67.

Unplugged the machine and removed and cleaned the reservoir.

On my return after the first warmup I replaced about a brew boiler's worth of water in a few stages. Same with the steam boiler.

Espresso was a good as ever. No hint of off-taste from water.

If you think about it, the brew boiler is at about 200* F. No mold or bacteria will survive that and as long as there is no access from outside there is little chance of contamination. The steam boiler is sterile.


#4: Post by jgood » replying to GC7 » Oct 09, 2019, 3:38 pm

I have been away for periods of about a month each and followed a similar protocol with my Quickmill -- drain the reservoir and then on return run a few reservoirs of water through the machine to replace the water in the brew boiler. This was based on advice from Chris Coffee.


#5: Post by Wattbe » Oct 09, 2019, 5:13 pm

Cheers for the replies - that's what I wanted to hear! I'll avoid draining the boilers and just flush fresh water through once I get back.