{HEAD ~ The second regiater} is connected to {TAIL ~ the ends} of the second air circuit and provides, in the first operational position, for atmospheric fresh air intake at the second heat exchange chamber and discharge into the residential area 
is connected to
{ HEAD ~ The second regiater } is connected to { TAIL ~ the ends } of the second air circuit and provides , in the first operational position , for atmospheric fresh air intake at the second heat exchange chamber and discharge into the residential area
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH