Stand-alone Boiler Control

Product Information


Designing your Hydronic heating system to function with multiple boiler stages by switching on/off multiple smaller capacity boilers will save money, energy, limit potential wear and tear and add a higher degree of comfort to your building.

Introducing the simplest, most intuitive control available to the hydronic industry, the CPU-0550. The unique design means minutes to learn, minutes to setup. The purpose and function of the CPU-0550 is to provide control for multiple applications from a single unit, reducing the number of different controls required for a system and on your shelf.

The CPU-0550 is designed to be a stand-alone unit with outdoor reset control. The control is designed to stage multiple boilers or control a single a modulating boiler with dedicated domestic hot water heating. This intuitive control allows for easy wiring, programming and all the system information is available on one screen with the full graphic multi-colored display.

5 Controls Modes in 1 Control

The CPU-0550 Stand-Alone outdoor reset control accommodates for staging, mixing, differential setpoint, dual Setpoint and pump sequencer applications in a condensed package with extensive flexibility.


The use of the CPU-0550 as a Boiler Control allows the capability to stage up to three (3) On/Off Boilers, or a single modulating Boiler with DHW (Domestic Hot Water) requirements using outdoor temperature reset. In addition, the CPU-0550 will control your system pump and with single or 2 stage boiler operation the control will run the boiler pump and DHW pump.

Mixing Control

This mode is used when running mixing pumps or valves in your hydronic system. Mixing configurations include injection modulating (0-10 VDC), and floating action valve. In this the control can run up to 2 on/off boilers or a single modulating boiler, depending on other options selected in the control.

Differential Setpoint Control

This mode is used when running a differential setpoint. In differential mode, the control will also send a modulating signal output based on how far the control is from the differential. This can be used to run a pump in modulating applications for constant flow.

Pump Sequencer Control

This mode is used to provide pump control for two pumps in a duty, standby situation. This control allows the system to sequence and cycle pumps, override pumps and turn the pumps off when the outdoor temperature goes above a certain value (WWSD). In this mode, a flow proof input and flow alarm can be utilized with the operation of your pumps.

Dual Setpoint Control

This mode is used when one or two independent setpoints are needed. Each setpoint is set up individually and each has its own thermistor input and relay outputs.

This product is discontinued. We will continue to support it, but no new units will be manufactured.

Product Features


Boiler run time rotation

Outdoor temperature reset

Boiler protection, setpoint and differential control

Pump Sequencer & Exercising

Stage up to 3 On/Off boilers or single modulating boiler (0-10 VDC)

Multiple mixing options

Multiple pump selection control

Warm weather shutdown

Manuals & Resources