304P Switching Relay – 4 Zones w/ Priority

Description

The Switching Relay 304P connects up to four thermostats and operates circulators to provide heating to a zoned hydronic heating system. Zone 1 has optional priority over zones 2 through 4 and can be used to provide heat to an indirect domestic hot water tank. The 304P includes optional exercising to prevent circulator seizure when not in use, and optional post purge operation of the last operating zone to maximize energy savings. The 304P provides a RoomResponseTM signal to modulating-condensing boilers to optimize comfort while improving boiler efficiency.

Features
Away signal shared between tekmar thermostats
CSA approved
Compatible with all low voltage thermostats
Four ground screws
Fuses protect transformers and pumps
LED for each zone, priority, end switch and RoomResponseTM
Post purge
Priority override
Pump exercising
RoomResponseTM signal
Top, bottom and back conduit knockouts
Two spare fuses included
Unlimited zone expansion
Zone priority

Specifications
Enclosure – Cover: ABS plastic, Base: galvanized steel, NEMA type 1
Approvals – CSA C US
Ambient conditions – Indoor use only, 32 to 122°F (0 to 50°C), RH 90% non-condensing
Power supply – 115 V (ac) ±10%, 60 Hz, 11 A
Transformer – 40 VA, expandable to 80 VA with additional transformer M3069 (sold separately)
Fuses – T5A 250 V slow blow, two spare fuses included
Pump relays – 230 V (ac), 5 A, 1/3 hp
Boiler XX end switch – 24 V (ac), 5 A
DHW end switch – 24 V (ac), 5 A
Mod boiler output – 0-10 V (dc) 500 ohm min load impedance / 4-20 mA 1 k ohm max load impedance