La Marzocco Strada User Manual

La Marzocco Espresso Machines Guideline
The La Marzocco espresso coffee machines work by forcing hot water under high pressure
through finely ground coffee held in a portafilter. The brewing process uses several key
components to accomplish this process.
Nearly every other espresso machine manufacturer uses a single boiler and heat exchanger
located inside the steam boiler. Water for brewing espresso is solely dependent on the
temperature of the single steam boiler and this creates inconsistent brewing and steaming
conditions, thus producing inconsistent drinks.
The La Marzocco espresso machine uses a unique two-boiler systems to isolate and perform
operations in the best possible conditions.
The rear boiler is dedicated to the steam and hot or tea water functions.
The front boiler has the sole purpose of providing brewing water at the correct temperature
and pressure for the coffee the barista is going to brew.
These temperature and pressure parameters are adjustable independently of any other
function of the espresso machine. They are also consistent though most any level of operation.
HOW DOES IT WORK?
Cold, filtered water enters the brewing boiler through a pump which raises the water pressure
to 9 bars to allow the water to flow through the finely ground coffee.
Then the water in the boiler is heated by a heating element, which is controlled by a
Temperature probe connected to a CPU which control and sends power to the element when
the water temperature is low and shuts off power to the element when the water is at
operating temperature.
This means the temperature of the coffee brewing water can be set precisely depending on the
operator's taste, the roast or blend of the coffee used.
When the barista puts the portafilter into the brewing group, it forms a watertight seal
between the portafilter and the group gasket.
When the user presses the brew switch, a solenoid valve opens and the pump generates
pressure to force the hot water from the boiler through the group and the diffusion screen and
screw, then into and through the ground coffee, producing the desired volume of espresso,
which is brewed into heated cups or shot glasses.
On automatic (AV) models, the water is measured by a flowmeter.

La Marzocco Strada Specifications

General

Type	Espresso Machine
Group Heads	1, 2, or 3
Pressure Profiling	Yes
PID Temperature Control	Yes
Body Material	Stainless Steel
Pump Type	Rotary
Pre-heating system	Yes
Steam Wand	Yes
Water Source	Plumbed
Power Requirements	220-240V, 50/60Hz
Dimensions	Varies by model
Weight	Varies by model

Summary

La Marzocco Espresso Machines Guideline

How Does It Work?

Explains the process of brewing espresso using hot water under high pressure.

Boilers

Groups

Group Valves

Flowmeter

Safety Relief Valve

Motor Pump

Thermostat

Heating Element

Control Box

Pressure Switch

Espresso Machine Troubleshooting

Inconsistent Shot Volumes

Addresses issues with inconsistent shot volumes and their solutions.

Inconsistent Shot Times

Addresses issues with inconsistent shot times and their solutions.

Water Leaks Around Portafilter

Addresses water leaks around the portafilter during brewing.

Leaking Steam Wand

Cold or Under-Extracted Espresso

Addresses problems with cold or under-extracted espresso.

Incorrect Dispensing Pressure

Addresses problems with incorrect dispensing pressure.

Espresso Machine Won't Steam

Addresses issues where the espresso machine does not steam.

Buttonpad Issues

High-Pitched Squeal

Steam Boiler Overfill

Daily Group Head Cleaning

Remove Basket and Clean

Gently remove the basket from the portafilter and clean.

Soak Portafilters and Baskets

Backflush with Blind Insert

Cycle the group on and off with a blind insert and cleaning solution.

Rinse Blind Filter

Clean Portafilter Engagement Area

Final Rinse and Backflush

Flush the group with an empty blind insert to remove residual detergent.

Remove and Rinse Inserts

Daily Diffuser Screen and Grouphead Cleaning

Remove Diffuser Assembly

Remove the portafilter, loosen the diffuser screw, and remove the assembly.

Clean Diffuser Screen and Screw

Scrub Diffuser and Gasket Area

Wipe Grouphead Area

Rinse and Re-assemble

Remove diffuser screen and screw from solution, rinse, and re-assemble.

Replace Portafilter Gaskets

Remove Diffuser and Old Gasket

Remove the diffuser assembly and pry the old gasket from the group head.

Prepare and Install New Gasket

Seat Portafilter Gasket

Relieve Airlock in Group

Loosen Bleeder Screw

Inspect Brewing System for Leaks

Check Group Valve Leaks

Check Expansion Valve Leaks

Inspect Pump and Expansion Valve Pressures

Adjust Pump Pressure

Adjust pump pressure to 9 bars while extracting espressos.

Adjust Expansion Valve Pressure

Turn expansion valve until dispensing pressure reads 12 bars.

Brewing Pressure Guidelines

Coffee is best brewed at 9 bars of pressure; higher pressure causes noise.

Expansion Valve Setting

Set the expansion valve to 12 bars to prevent system damage.

Steam Tip Clogged

Clear Steam Tip Holes

Run Steam Through Tip

Soak Steam Tip

Re-install Steam Tip