alexander alexandrowitz

Fish in the Sea

Sun, 15 Feb 2026 00:00:00 +0000

A small browser game created by my son with the help of AI: Navigate your fish through the ocean, collect all the coins, and watch out for the oil spills!

Controls

Arrow up / Arrow down (or W / S): Swim up and down
Touch: Steer toward your finger position (mobile)

Play

Play Fish in the Sea

Mission NYC - Rooftop Parkour

Tue, 10 Feb 2026 00:00:00 +0000

A small browser game developed by my son using Claude Code: Jump from rooftop to rooftop, swing on ropes, and deliver the briefcase safely - but watch out, don’t fall off the skyscrapers!

Controls

Arrow keys left/right: Move
Arrow up / Space: Jump
Double Space: Double jump
Slide on wall + Space: Wall jump
Rope: Automatically grabbed
Space on rope: Jump off

Play

Play Mission NYC - Rooftop Parkour

A Smart Home Challenge: Resolving a Viessmann Heat Pump Problem

Fri, 28 Jun 2024 00:00:00 +0000

Today, I want to share a personal story about how I discovered and successfully resolved an issue with my Viessmann heat pump. A smart home is full of little technical marvels, but occasionally, challenges arise. This experience has taught me the importance of collecting and analyzing data to effectively solve technical problems.

My Viessmann Heat Pump and the First Winter

We have had our heat pump in operation since moving in 2021. During the first winter, I noticed an issue: the temperature of the hot water tank rapidly dropped by about 1 degree per hour as soon as the heating function was turned on. At that time, I lacked the knowledge and technical means to accurately identify the problem.

about

Sun, 23 Jun 2024 00:00:00 +0000

My name is Alexander Alexandrowitz, and I was born in Aachen in 1989. As a Cloud Engineer with a background in software development, I have a profound passion for automation, Python programming, and smart home technologies. I am experienced in working with Kubernetes, holding both CKAD and CKA certifications.

Beyond my technical pursuits, I am also interested in music, which inspires me.

imprint/privacy

Sun, 23 Jun 2024 00:00:00 +0000

Datenschutzerklärung

Verantwortlicher

Alexander Alexandrowitz
Lilienweg 5
52457 Aldenhoven
info[at]alexandrowitz.de

Arten der verarbeiteten Daten

Bestandsdaten (z.B., Personen-Stammdaten, Namen oder Adressen).
Kontaktdaten (z.B., E-Mail, Telefonnummern).
Inhaltsdaten (z.B., Texteingaben, Fotografien, Videos).
Nutzungsdaten (z.B., besuchte Webseiten, Interesse an Inhalten, Zugriffszeiten).
Meta-/Kommunikationsdaten (z.B., Geräte-Informationen, IP-Adressen).

Kategorien betroffener Personen

Besucher und Nutzer des Onlineangebotes (Nachfolgend bezeichnen wir die betroffenen Personen zusammenfassend auch als „Nutzer“).

Zweck der Verarbeitung

Zurverfügungstellung des Onlineangebotes, seiner Funktionen und Inhalte.
Beantwortung von Kontaktanfragen und Kommunikation mit Nutzern.
Sicherheitsmaßnahmen.
Reichweitenmessung/Marketing.

Verwendete Begrifflichkeiten

„Personenbezogene Daten“ sind alle Informationen, die sich auf eine identifizierte oder identifizierbare natürliche Person (im Folgenden „betroffene Person“) beziehen; als identifizierbar wird eine natürliche Person angesehen, die direkt oder indirekt, insbesondere mittels Zuordnung zu einer Kennung wie einem Namen, zu einer Kennnummer, zu Standortdaten, zu einer Online-Kennung (z.B. Cookie) oder zu einem oder mehreren besonderen Merkmalen identifiziert werden kann, die Ausdruck der physischen, physiologischen, genetischen, psychischen, wirtschaftlichen, kulturellen oder sozialen Identität dieser natürlichen Person sind.

Use your heatpump efficiently with sun energy

Sun, 23 Jun 2024 00:00:00 +0000

Prerequisites

Up-to-date Home Assistant installation
Photovoltaic system that sends production data to Home Assistant
Heat pump that can be controlled by Home Assistant
A helper variable (type bool) which indicates a photovoltaic electricity surplus
An integration to get the remaining photovoltaic production of the day (Forecast Solar integration)
Important: I have a Viessmann heat pump (Vitocal 200a), which might operate differently from yours
Note: You might not be able to use this automation directly (Ctrl+C; Ctrl+V) in your setup, but it should serve as a good starting point.

How it works

I have been refining my perfect automation for over one and a half years and am now quite satisfied with it. Since our photovoltaic system doesn’t have a battery, I was looking for a solution to enable my heat pump to use as much clean energy as possible during sunlight hours. Essentially, I increase the temperature of my hot water tank when certain conditions are met.