·Electronic Fuse - Auto reset ·Robust Transformer (Enough to handle up to 15 zones) ·Double-sided printed circuit board construction ·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 ·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 |
