I had intended this entry to be about our heating system and DHW, but due to the interest and debate on MVHR silencers, have brought this entry forward.   As reported in a previous blog entry, I’ve been aware of fan noise being emitted from the individual room supply and extract terminals.  The valves themselves do go some way of dampening down the noise, so acoustic valves may well be a good solution, but I decided to go down the route of building my own silencer following some discus