SZ2165

Boiler Controller

Description

The SZ2165 is a microprocessor based boiler controller. It is designed for use on multi-stage boiler applications and includes chiller support and control.

Features:

  • Stand-alone or network operation
  • 365-day time clock with two holiday schedules, automatic leap year and daylight savings correction
  • No backup battery required for control parameters, schedule or clock
  • Hot water supply and return temperature inputs
  • Chilled water supply and return temperature inputs
  • Two digital outputs for chillers
  • One digital output for alarm
  • Mixed water temperature input
  • Outdoor air temperature input
  • Outdoor air reset control
  • Two digital inputs for pump status
  • External time clock input
  • Local override and remote override capability
  • Six digital outputs for boilers, pumps and boiler stages
  • Adjustable offsets and differentials on digital outputs
  • Lead/Lag sequencing of up to four boilers
  • Analog input for pressure control
  • Two modulating analog outputs for valves and VFDs
  • Adjustable P+I+D control on modulating outputs
  • LEDs for monitoring status
  • Automatic rotation of pumps
  • Automatic rotation of boiler and chiller stages
  • Domestic hot water function
  • Pump lube feature
  • Selectable normally open or normally closed relay outputs

Call to order:

1-800-288-9383

Specs & Docs

Specifications:

General

Accuracy: +/- 0.5%
Programming: EIA RS485 interface
Communications: RS485, half duplex
Memory backup: Non-volatile EEPROM, no battery required

Environmental

Operating temperature: 32 to 131°F (0 to 55°C)
Operating humidity: 0 to 100% RH, non-condensing
Storage temperature: 14 to 140°F (-10 to 60°C)

Electrical

Supply voltage: 24 VAC +/-20%
Inputs: Six 1000 Ω PtRTD, momentary override, five digital (dry contact) and one 4 to 20 mA DC analog
Range: Hot water supply and return: 40 to 240°F
Chilled water supply and return: 0 to 100°F
Mixed water: 20 to 220°F
Outdoor air: -40 to 160°F
Outputs: Nine digital (SPST dry contact, 24 VAC @2 A) and Two 4 to 20 mA DC analog
Analog input impedance: 250 Ω
Max. load resistance (analog output): 600 Ω
Common mode rejection: 100 db @ 60 Hz
Power consumption: 15 VA max.

Specifications subject to change without notice.