My recirculating pump (which is attached to a water heater to heat two basement rooms via a hot water pipe system) was run dry for two nights (at least 24 hrs). Was the pump damaged? Was the the life of the pump shortened thereby?
Sight unseen IMPOSSIBLE to TELL YOU. BUT if your lucky to have had a B&G circulator they are thermostatically protected from over heating. A lot of the newer circulators also do not require water as a lubricant as they did years ago.
Best suggestion fill the system TURN up the thermostat and FEEL the return lines to see if water is circulating TA DUM. Really hard to figure out huh?
By the way just in case your the least bit interested did you know that using a domestic hot water heater for heating is illegal? The reason is
1- Stagnant water in the heating part when not in use can cause legionnaires disease as the water temperature in a domestic tank is not high enough to kill this type of germ, But hey your LICENSED PLUMBER did explain this to you when they installed this correct?
2- You are also aware that the base board used for heating is not designed for the kind of pressure than can develop in a domestic hot water line (150 PSI) but a hydronics system is normally operating below 30 PSI.
3- A hot water heater does NOT have a low water fuel cut off and only has a T&P and no other safety controllers Only one operating control, BUT hey it is sure a lot cheaper then having a safe system and that is all that counts.