Another object of this invention is to provide {HEAD ~ a device} which automatically switches between thermal operating speed and {TAIL ~ circulation speed} upon pre selected conditions determined by a conventional thermostat 
automatically switches between
Another object of this invention is to provide { HEAD ~ a device } which automatically switches between thermal operating speed and { TAIL ~ circulation speed } upon pre selected conditions determined by a conventional thermostat
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH