It looks like this topic is beat to death! Just bought a vac. home. Just want to keep pipes from freezing in winter. Present t stat has R,R,O, black(W label) and G. Bought Honeywell RTH9585WF smart t stat. Can I hook up AC and heat? Though only controlling heat remotely. WITH a 24v transformer? Option B (approved by H’well) is to switch out t stats each change of seasons. Doable but a PIA