@thestoicplumber They basically use them as a way to meet the energy efficiency points system on new build homes. Each home must have say 100 points and these count as a percentage of that. Prevents builders having to install solar and more expensive products
@thestoicplumber We fit them on combi boilers in uk, feeding the cold supply to the shower. As you run the shower the waste water warms the cold feed coming back to the shower saving you a few degrees of hot water.
@TRobinsonNewEra The place is a shit hole ! Did some gas training there, had metal detectors/ scanners due to all the people bringing knives into to college