If you have a triple aquastat on the boiler, it will maintain temperature in
the boiler. You need to separate the two zones, as Ed said, by either two
circulators, or one circulator and two zone valves. Zone valves would be
easier as you don't have to add switching relays. Each thermostat controls
its respective zone valve and each zone valve has an end line switch that
turns on the boiler by connecting to the "tt" on the aquastat relay that you
currently have



"balboni" wrote in message
oups.com...
I would like to zone my basement hot water radiators separately from
the rest of the house since it doesn't seem to get warm enough there
before the thermostat upstairs turns the system off. I would like to
install a zone valve that controls the water to the upstairs. I would
also install a thermostat downstairs. I have a Honeywell Aquastat
relay type L8148A on the system (hooked up to the upstairs thermostat).
I believe I need to wire the upstairs thermostat to the zone valve and
then to the Aquastat and that I need to wire the downstairs
theromostat to the Aquastat as well. Is this the proper way to wire
the system? Can you wire to thermostats to the same screws on the
Aquastat?