I decided to put the recommended temperature surfing standard times [source: Web log of Mythos, Rini, Simon and Debbie (MRSD), here] for the Rancilio Silvia coffee machine up as diagram (rather than text print out).

For anyone that also wants this graphically, here you go.

With some text in the diagram, this is an option:

PDF: http://www.swisswuff.ch/files/ranciliosilvia/tempsurfing-diagram-ranciliosilvia.pdf

Table of Contents

How to temperature surf a Rancilio Silvia step by step

The line by line instructions cited from the source [Web log of Mythos, Rini, Simon and Debbie (MRSD), here] :

Warm up the machine for at least 30-60 min (or brew at least 2 x double shot espresso and throw them down the drain.. not recommended though)
Current State: Indicator light of heating boiler = OFF
Turn ON brew button to run cold water into boiler until indicator light is ON
Reason: Cold water makes the boiler temperature drop and triggers the boiler to start again when temperature is below 86 C/186 F
The 0 seconds moment: Wait till the indicator light of heating boiler = OFF and immediately start a stopwatch (clock, mobile phone, watch, whatever). Now, the boiler temperature is 102 C/215 F
Precisely wait for 30 seconds for the machine to cool down, as the boiler heating as shown by the indicator light is now off. Reason: The internal temperature keeps climbing because of pressure inside the boiler even the boiler is turned off. It reaches at 116 C/240 F (which is 30 seconds) and boiler starts to cool down by itself
Now, at 30 seconds, turn ON brew button to run cold water into boiler for 5 seconds and capture it in your cup (it is OK to maybe heat it a bit, then pour that water away). Reason: This procedure is called “cold flush” to bring down the temperature to 110 C/ 230 F, you should see a lot of steam in first 3 seconds *
Turn OFF brew button at 35 seconds (read stopwatch)
Now, put the portafilter + cup under the brew head (You have around 15 seconds time to do so)
Turn ON brew button at 50 seconds (read stopwatch) to brew your coffee. Note: At this point, cold water comes in continuously for the next 25 seconds + temperature offset between the brewhead and boiler, so the final average temperature would be ideal when it touches the coffee which around 198 F to 204 F (92 C to 95 C) for the next 25 seconds.
Reset stopwatch and start it from 0 (Stopwatch at 0 seconds)
Your espresso should starts brewing, if tamped and grind properly, your espresso should finish at 25-30 seconds.
Note: the boiler indicator light = OFF all the time until the end, the indicator light will turn ON automatically at around 20 seconds **
Turn OFF brew button at 25-30 seconds, depends on coffee, tamp and grind

* If you don’t see steam, your machine has not been warmed up enough in (1)

** If you don’t warm up in (1), the boiler isn’t hot enough and the boiler starts to kick in too early, giving you the wrong temperature.

Supplement: temperature surfing a Solis Crema SL 70 coffee machine

I am currently trying to use up (as in: until it falls apart) an old Solis Crema SL 70 coffee machine I still had sitting around. Playing across the options of different temperature surfing results, I find that emptying a whole 2 DL cup of hot water into a cup (discarding that) and pulling the shot immediately after that – with the thermostat clearly indicating that the heating is on – gives a lot better results as to crema and taste than warmer temperatures. So I drain around 2 DL of water before making coffee. Without any particular wait in between. This is at around 400 meters above sea level.