This is an example of how to use zone valves for each zone instead of individual pumps. Each Zone Valve is attached to a Zone Valve Controller and to an individual Thermostat. When a thermostat calls for heat - the Zone Valve Controller starts the boiler and any pumps needed for the primary loop or if required a secondary loop.
You will notice that in the Picture Below there is a mixing valve to reduce the boiler water tempeature that feeds 6 Zones with Zone Valves. These Zone Valves could feed hydronic radiators or hydronic baseboard convectors. This could also be used for much lower set temperature that could be used for 6 pex radiant floor heat zones.
This is only an example. Actual layouts vary from job to job.
List of materials needed for a project like this (Click Link below to Purchase Product and see more Information)
Hydronic Heating Side (Trim)
Quantity 1 - Gas or Electric Heating Boilers
Quantity 6 - Zone Valves
Quantity 1 - Hydronic Heating Mixing Valves
Quantity 18 + - Ball Valves for Hydronic Heating Side
Quantity 6 + - Boiler Drain and Hose Bibs
Quantity 1 - Temperature Guages and Tees
Qunatity 1 - Zone Valve Controller (not shown)
Quantity 6+ - Hydronic Heating Thermostats and Floor Sensors
Quantity 1 - Taco Flo Checks Valves
Hydronic Heating Side (Distribution)
Quantity X - Hydronic Baseboards (Depends on System)
X = Various Amounts of Product needed - dependant on actual system