In a word, yes. Either using the built in serial, assuming it can manage 4800 8N1, or using software emulation. You should then be able to connect to either a TRV or a stats hub - probably most usefully, to a stats hub. Note that both run at 3.3V, however, a TRV with a motor draws about 0.5A when doing a motor wiggle on boot. A stats hub (REV11) can be powered directly from 3.3V out on the Pi.