Hot water home heating system maintenance requires an annual inspection by a professional service technician and an annual flush of mineral deposits and rust from the boiler. Periodic maintenance tasks include checks of boiler water level, proper slope of all radiators and pipes, and sufficient air in the expansion tank.
The optimum water level in the boiler is half full. Low water levels can cause inadequate heating. Recurring low water levels in the boiler indicate the presence of one or more water leaks. Radiators and pipes must slope downward toward the boiler to provide sufficient heat and prevent knocking noise from the system. Insufficient air in the expansion tank generates increased pressure within the system and forces water from the safety relief valve located above the boiler.