Domestic Passive Ventilation with Heat Recovery (PVHR): Performance Criteria, Tests and Operational Variations

19th-century thermosiphon ventilation and its potential for heat recovery in buildings today

“…Undeterred by concerns for flow stability, researchers have investigated variations of low-pressure heat exchangers for buoyancy ventilated buildings, including rotary wheels and heat pipes, arguing that the weak exhaust flow can be assisted with low-power fans, wind-cowls, or solar heating. 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 …”