# Doing the Maths **URL:** \ **Category:** Heatpump\ **Created:** [26 April 2026 07:32 UTC](https://community.openenergymonitor.org/t/doing-the-maths/29937 "2026-04-26T07:32:24Z")\ **Posts on this page:** 1\ **Showing post:** 15
**Author:** ![Timbones](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/timbones/32/20308_2.png) [@Timbones](https://community.openenergymonitor.org/u/Timbones)\ **Post date:** [13 August 2026 23:34 UTC](https://community.openenergymonitor.org/t/doing-the-maths/29937/15 "2026-08-13T23:34:46Z")
> [@purrcat](#): > > Hence the need for sizeable radiators if a low flow temperature is to be maintained. You might want to look into a different type of radiator that has a heat exchange (and optionally fans), which has significantly higher heat output than a traditional passive design. > [@Experience with 'Jaga Strada' radiators/fancoils?](https://community.openenergymonitor.org/t/experience-with-jaga-strada-radiators-fancoils/30128): > > I’m looking to replace several standard large K2/K3 radiators in our house with ‘Jaga Strada’ fancoil-style radiator units (passive, without fans, small heat exchanger with thin aluminium fins attached to copper pipe). System is a Vaillant Arotherm Plus 7kW, with ~40sqm of UFH in screed on the ground floor and bathroom, and 10x K2/K3 radiators everywhere else (average size: 1400x600), so a good amount of system volume (no volumiser/buffer). ~5kW heat loss (-2C/22C), real-world design flow temp:… --- _[View the full topic](https://community.openenergymonitor.org/t/doing-the-maths/29937)._