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Four Port Valve

 

After a few experiments I decided I wanted the following options for the input air source.


1) Fresh air from roof top. Function as a vanilla balanced ERV ventilation system, all exhaust air passes through the heat exchanger, all incoming air is warmed by the heat exchanger.


2) Loft air, typically warmer if the Sun is out even on a cold day. Reduce need for heating during the day.


3) Fresh Air bypassing the heat exchanger to reduce the need fore running the heat pump on sunny days when the air temperature is still quite low.


4) Block all four ports to prevent air moving from convection or an open window raising or reducing air pressure in the room.


So the four port valve was born.


ts got a dual drive now which works really well. The wooden gear was inspired by the Marble Machine i have toughened the teeth with Epoxy now which make it quite substantial.






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