The Heat Source Paradox

It is not a paradox - it is a straight-forward relation between a heat pump system's key data: The lower a heat pump's performance factor is, the smaller the source can be built. I would not write this post, hadn't I found a version of this statement with a positive twistย  used in an advert! … Continue reading The Heat Source Paradox

The Collector Size Paradox

Collector harvest does not change much if we only use half the collector. Perhaps counter-intuitive but explained by the characteristics of heat exchangers connected in series: Especially if one of the heat exchangers (in the tank or collector) is already much superior to the other one, it does not help to optimize the good one further.

Data for the Heat Pump System: Heating Season 2016-2017

I update the documentation of measurement data [PDF] about twice a year. This post is to provide a quick overview for the past season. The PDF also contains the technical configuration and sizing data. Based on typical questions from an 'international audience' I add a summary here plus some 'cultural' context: Building: The house is … Continue reading Data for the Heat Pump System: Heating Season 2016-2017

Hacking My Heat Pump – Part 2: Logging Energy Values

In the last post, I showed how to use Raspberry Pi as CAN bus logger - using a test bus connected to control unit UVR1611. Now I have connected it to my heat pump's bus. Credits for software and instructions: juerg5524.ch messpunkt.org SK Pang Special thanks to SK Pang Electronics who provided me with CAN … Continue reading Hacking My Heat Pump – Part 2: Logging Energy Values

How Does It Work? (The Heat Pump System, That Is)

Over the holidays I stayed away from social media, read quantum physics textbooks instead, and The Chief Engineer and I mulled over the fundamental questions of life, the universe and everything. Such as: How to explain our heat pump system? An astute reader suggested to create an 'animation' of the gradual evolution of the system's … Continue reading How Does It Work? (The Heat Pump System, That Is)

Heat Pump System Data: Three Seasons 2012 – 2015

We have updated the documentation of monthly and seasonal measurement data - now including also the full season September 2014 to August 2015. The overall Seasonal Performance Factor was 4,4 - despite the slightly lower numbers in February and March, when was the solar collector was off during the Ice Storage Challenge. Edit: I have … Continue reading Heat Pump System Data: Three Seasons 2012 – 2015

How to Evaluate a Heat Pump’s Performance?

The straight-forward way is to read off two energy values at the end of a period - day, month, or season: The electrical energy used by the heat pump and the heating energy delivered. The Seasonal Performance Factor (SPF) is the ratio of these - the factor the input electrical energy is 'multiplied with' to … Continue reading How to Evaluate a Heat Pump’s Performance?