Argo 2 Zone Expandable Switching Relay

Electronic Fuse - Auto reset Robust Transformer - Enough to handle up to 15 zones Double-sided printed circuit board construction - 100% factory tested for reliability Clearly marked terminals with clamping plates Separate xx (isolated switch) & ZC/ZR Relays protect boiler aquastat Priority Safety Timer - Ensures other zones get heat every 30 minutes & prevents freeze-ups 5-second Time Delay for boiler shut-off Relay Diagnostic Light - Easily seen through window on cover Premium plug-in replaceable relays 24 VAC Transformer Terminals Plug-in, Add-on Zone Modules (AD-1 or AD-4) Switchable Priority High relay load rating - 1/3HP