In Nofo's SPSSD, how would the wiring look if you are using a Grundfos Alpha for your main load circulator? It does not have any wiring going to it, just a power cord.
From the SPSSD:
"First, the zone valve limit switches are removed from the oil boiler demand input and connected to the 24vac thermostat transformer (see schematic).
Second, we need a 24VAC relay that we energize when any of the zone valve limit switches are closed. This relay will turn on the Load Circulator.
Third, we need a 24VAC relay for the oil boiler demand input - when this relay is energized, it creates a closed circuit that turns on the oil boiler. This takes the place of the zone valve limit switches.
Finally, we need an aquastat at the top of our storage with contacts that close only when the storage temperature drops below the minimum usable temperature - we’ll say 140 degrees for this example. The signal from the zone valve limit switches passes through this aquastat before going to the oil boiler demand relay. In that way, if the storage is above 140, the oil boiler will not come on when the zones call for heat"
So, how do I remove the limit switches from the zone valves and make the Alpha come on when the house calls for heat instead of the circulator on the oil boiler?
thx, Pat
From the SPSSD:
"First, the zone valve limit switches are removed from the oil boiler demand input and connected to the 24vac thermostat transformer (see schematic).
Second, we need a 24VAC relay that we energize when any of the zone valve limit switches are closed. This relay will turn on the Load Circulator.
Third, we need a 24VAC relay for the oil boiler demand input - when this relay is energized, it creates a closed circuit that turns on the oil boiler. This takes the place of the zone valve limit switches.
Finally, we need an aquastat at the top of our storage with contacts that close only when the storage temperature drops below the minimum usable temperature - we’ll say 140 degrees for this example. The signal from the zone valve limit switches passes through this aquastat before going to the oil boiler demand relay. In that way, if the storage is above 140, the oil boiler will not come on when the zones call for heat"
So, how do I remove the limit switches from the zone valves and make the Alpha come on when the house calls for heat instead of the circulator on the oil boiler?
thx, Pat
