They got water in the manifold today, so we could check for any leaks in the new connections before we finish drywalling the first floor. The water flowed into the radiators for the first time since August! This is the first time water flowed into the bathroom radiant floor too. Amazingly, the only leaks were the two places we reused old connection parts- fairly easy fixes. Monday they will be back to power up the pumps so we can use the radiators to heat it up around here!