The hydronic system shown was intended to provide heat to a radiant floor slab and an indirect water heater.
The hydronic system shown below was intended to provide heat to a radiant floor slab and an indirect water heater. Either load can independently call for heat as needed based on thermostat settings. The owner sets the space heating thermostat back 5 degrees F at bedtime, and then resets it to normal comfort temperature when he rises at 6 a.m.
His complaint is that the water temperature gets progressively cooler during his morning shower, even though he insists the boiler is firing nonstop during this time. He’s also wondering why there are rust spots forming on the boiler’s galvanized vent pipe, even though it’s only a few months old.
Can you spot some design details that are likely causing these problems?