Full steam ahead.......
Welcome to the year 2000. Hopefully all finds you
well and that you had a prosperous holiday season.
All those repairs and maintenance items that you meant
to get to before the holidays are now haunting you
and you know you need to fix them. So this month we
will look at a few of the more common repair and maintenance
items required to keep your espresso machine in good
working order.
One of the most common repairs to espresso machines
seems to be steam valve repair and steam wand replacement.
After months of turning the steam knob or pulling
the steam lever in order to steam volumes of milk,
you start to notice that no matter how hard you try,
the steam wonąt stop leaking. Chances are that the
seal within the steam valve is crushed, and will not
seat properly anymore. Now at this point you have
a couple of choices. First you need to decide if you
want to rebuild your valve or have a technician do
the work and also, do you rebuild the valve or just
replace it? Steam valve replacement on most espresso
equipment is relatively easy and can be accomplished
in less than an hour depending on your mechanical
abilities. Replacing the valve, rather than repairing
it will ensure a leak free installation in a short
time frame. Now depending on your ability you may
wish to rebuild the valve, this involves a bit more
time and in some cases specialized tools to complete
the job correctly. One of the most important aspects
to rebuilding a steam valve is to make sure that the
valve seat is in good condition and free from imperfections.
The seat is where the rubber seal sets to stop the
flow of steam. If the seat has any imperfections the
seal will not seat and will cause steam to leak past.
The best way to remedy this problem is to either replace
the seat or use a seat cutter to put a new surface
on the seat. Once this part of the rebuilding process
is complete you can now start to reassemble the valve.
While you have the valve apart it is suggested that
you also replace any stem packing as well as body
gaskets that seal the valve and associated fittings.
It is also a good time to look at the steam pipe wand.
The steam wand is an area of your machine that requires
constant maintenance as well as replacement. The first
thing I want to say here is that most health departments
require the steam wand on your espresso machine to
be clean at all times. The reason for this is to reduce
bacterial contamination of the milk that you will
be using in your finished product. Milk allowed to
build on the outside of steam wands will create not
only an unsightly mess but could also cause contamination.
Chances are if I walk into a shop that has milk caked
on the steam wands I also pass on the thought of purchasing
a drink there. One of the most common service calls
to our shop is with regard to plugged steam tips.
The scenario goes like this: The barista says the
machine has hot water and it makes coffee well, but
there is no steam. They have tried every thing and
they canąt figure out what is wrong. Well, after many
years of going out on this call I now try to resolve
the problem on the telephone. Thus saving my customer
a few bucks and also the embarrassment of completing
a task that should be part of their daily routine.
I often say to the Barista, O.K. go to the supply
drawer and get your espresso machine steam wand fix
it tool i.e.: a paper clip and then use the paper
clip to poke the holes in the steam tip. Ninety nine
percent of the time this resolves the problem and
steam is now free to travel through the steam tips
once more. This problem can be alleviated rather simply
be purging the steam wand of excess milk at the end
of each use. To reduce the amount of milk build up
on the outside of the wand, simply wipe the wand with
a soft cloth after each use. Combine both efforts
in one sweeping motion at the end of each use and
you should have a very sanitary steam wand in good
repair. If for some strange reason milk is allowed
to build up on the wands, it is not suggested that
you use any sharp item, that will remove the chrome
finish from the steam wand, a simple way to remove
this milk scale is to wrap a towel around the wand
and then crack open the steam valve allowing the steam
to soften the milk. Once the milk build up is soft
it should simply wipe off. A lot of baristas soak
the steam wands in hot water overnight. This is not
a recommended way of maintaining your wands, but many
shops do this. My contention is that if properly maintained
throughout the day, there should be no need to soak
them in hot water.
If you find it necessary to replace the wand on your
machine the process is fairly straight forward. Espresso
machines use two types of steam wand mountings. The
first and most prevalent is the ball and steam nut
mount. If your steam wands rotate 360 degrees you
have ball and steamnut style wands. The second style
is the bayonet mount. If your steam wands move only
forward and backward then you have bayonet mounts.
to replace a bayonet mount wand you must remove a
retaining nut and in somecases a circlip to remove
the wand. Replacement is as simple as removing the
old wand and replacing the bayonet gaskets then replacing
the wand and retaining nut and circlip. The replacement
procedure for the ball type wand is to simply loosen
the steam nut from the steam valve and then remove
the wand. Remember to replace the wand retention seat
and spring as well as any associated o rings when
doing this style of steam wand.
With a little bit of patience and care, you can keep
your espresso machine in tip top shape and save a
few bucks by doing it your self. It is really a good
idea to have a understanding of how an espresso machine
works, this hopefully will help with your overall
understanding of the beverages it can create.
