Indirect HW shut off

In the summer months I normally turn off my furnace (HW Gas) when away on weekends of vacation..., To save the gas on heating the Indirect HW. In winter months I lower my thermostats to 55 but I still an generating HW on my third zone. Can I put a switch on my aquastat to disable the circuit to the zone Valve if I am away for a long length of time. No sense heating the water if no one is using it. If so, what kind of switch?

Any comments?

Any single pole switch rated for at least 24 VAC should be fine. I'd probably just use a simple light switch.