Simple to install with a straight in-line full flow design

Integral patented air release mechanism

Simple to install with a straight in-line full flow design

Integral patented air release mechanism

Simple to install with a straight in-line full flow design

Integral patented air release mechanism

Simple to install with a straight in-line full flow design

Integral patented air release mechanism

Simple to install with a straight in-line full flow design

Integral patented air release mechanism

Simple to install with a straight in-line full flow design

Integral patented air release mechanism

No bypass, isolating valves or replacement filters to clog and reduce flow

Dirt can be flushed while the system is in full operation

Quiet operation

Minimum pressure drop

always constant

Increased component life

Reduced oxygen-based corrosion and pump cavitation

Provides optimum heat transfer

Optional removable head for bundle inspection

No bypass, isolating valves or replacement filters to clog and reduce flow

Dirt can be flushed while the system is in full operation

Quiet operation

Minimum pressure drop

always constant

Increased component life

Reduced oxygen-based corrosion and pump cavitation

Provides optimum heat transfer

Optional removable head for bundle inspection

Front Diagnostic Lights

Switchable Priority

Built-in Priority Protection

Simplified Wiring

Premium Sealed Relays

Compact Design

Fuse Protected

100% Factory Tested

Isolated End Switch

Contractor Friendly PC Board Layout

Universal Thermostat Compatibility

24 Volt Power Output for hard wired thermostats

Field Replaceable Transformer

Front Diagnostic Lights

Switchable Priority

Built-in Priority Protection

Simplified Wiring

Premium Sealed Relays

Compact Design

Fuse Protected

100% Factory Tested

Isolated End Switch

Contractor Friendly PC Board Layout

Universal Thermostat Compatibility

24 Volt Power Output for hard wired thermostats

Field Replaceable Transformer

Front Diagnostic Lights

Switchable Priority

Built-In Priority Protection

Simplified Wiring

Premium Sealed Relays

Compact Design

Fuse Protected

100 Percent Factory Tested

Isolated End Switch

Contractor Friendly PC Board Layout

Universal Thermostat Compatibility

24 Volt Power Output for Hard Wired Thermostats

Field Replaceable Transformer

Add-On Power Control Plug

Built-In Post Purge and Pump Exercise Functions

Switchable Primary Circulator Output

Two Boiler Contacts, Utilizes Full Functionality of Mod-Con Boilers

Expandable to 20 Zoning Panels

Interface with EXP Zone Valve Controls

UL Approved

Made in USA

Front Diagnostic Lights

Switchable Priority

Built-In Priority Protection

Simplified Wiring

Premium Sealed Relays

Compact Design

Fuse Protected

100 Percent Factory Tested

Isolated End Switch

Contractor Friendly PC Board Layout

Universal Thermostat Compatibility

24 Volt Power Output for Hard Wired Thermostats

Field Replaceable Transformer

UL Approved

Made in USA

Microprocessor-based control designed to regulate the supply water temperature of a single boiler, based on the outdoor temperature

The FuelMizer is a boiler reset control and switching relay in one unit

it is ideal for retrofit application, but may also be used in new installations. Its quality features include full outdoor boiler reset control: it can control the system or zone valve circulator or it can override outdoor reset when DHW tank is calling. Its easy to install and set and will not affect the boilers warranty. Front mounted LED lights offer full diagnostic information

The FuelMizers typical energy savings is about 14%, with some customers experiencing 30%

Front Diagnostic Lights

Switchable Priority

Built-In Priority Protection

Simplified Wiring

Premium Sealed Relays

Compact Design

Fuse Protected

100 Percent Factory Tested

Isolated End Switch

Contractor Friendly PC Board Layout

Universal Thermostat Compatibility

24 Volt Power Output for Hard Wired Thermostats

Field Replaceable Transformer

UL Approved

Made in USA

Brass threads provide a metal-to-metal seal that ensures a leak-free installation

Integrated wrench flats enable secure installation without damage to the housing

McDonnell and Miller's patented Self-cleaning probe minimizes scale build-up and extends the recommended cleaning interval to 5 years

"Plug and Play" wiring harnesses are available for most residential gas-burning boilers

Electronic operation

Easy to install and wire

Red low water indicating LED

Green power indicating LED

No blow down required

Provide Intermediate Switching of a Line Voltage Device from a Low Voltage Controller

Integral Transformer Provides Low Voltage Power For Control Circuit

Integral Transformer Provides Low Voltage Power for Control Circuit

The RA832A is a DPST Relay, One Relay Pole is Designed for Low Voltage or Millivoltage (PowerPile) Auxiliary Load, Two Other Relay Poles are for Line Voltage Loads

Provides Intermediate Switching of a Line and Low Voltage Devices from a Line or Low Voltage Controller and is Typically Applied in Hydronic Heating Systems

Replaceable Socketed Relays

Two Troubleshooting LED

Replaceable Transformer Fuse

Push to Test Button

Low Voltage Contact Rating for PowerPile Applications

Long Life DC Relay Drive Control Technology

No Clog Vent

Dirt and Debris Resistant

360 Degree Adjustable Collar Ring for Installation Flexibility

Stainless Steel Concentrator Which Eliminates Gurgling Noise

No Clog Vent

Dirt and Debris Resistant

360 Degree Adjustable Collar Ring for Installation Flexibility

Stainless Steel Concentrator Which Eliminates Gurgling Noise

Bronze Body for Rigid Construction

Guarantees Fast Start up with Automatic Venting

Micro-Bubble Concentrator has Three Times the Impact Area of Other Products

Helps Prevent Corrosion of System Components

Improves System Efficiency

Made in USA

No Clog Vent

Dirt and Debris Resistant

360 Degree Adjustable Collar Ring for Installation Flexibility

Stainless Steel Concentrator Which Eliminates Gurgling Noise

Bronze Body for Rigid Construction

Guarantees Fast Start up with Automatic Venting

Micro-Bubble Concentrator has Three Times the Impact Area of Other Products

Helps Prevent Corrosion of System Components

Improves System Efficiency

Made in USA

No Clog Vent

Dirt and Debris Resistant

360 Degree Adjustable Collar Ring for Installation Flexibility

Stainless Steel Concentrator Which Eliminates Gurgling Noise

Bronze Body for Rigid Construction

Guarantees Fast Start up with Automatic Venting

Micro-Bubble Concentrator has Three Times the Impact Area of Other Products

Helps Prevent Corrosion of System Components

Improves System Efficiency

Made in USA

No Clog Vent

Dirt and Debris Resistant

360 Degree Adjustable Collar Ring for Installation Flexibility

Stainless Steel Concentrator Which Eliminates Gurgling Noise

Bronze Body for Rigid Construction

Guarantees Fast Start up with Automatic Venting

Micro-Bubble Concentrator has Three Times the Impact Area of Other Products

Helps Prevent Corrosion of System Components

Improves System Efficiency

Made in USA

No Clog Vent

Dirt and Debris Resistant

360 Degree Adjustable Collar Ring for Installation Flexibility

Stainless Steel Concentrator Which Eliminates Gurgling Noise

Bronze Body for Rigid Construction

Guarantees Fast Start up with Automatic Venting

Micro-Bubble Concentrator has Three Times the Impact Area of Other Products

Helps Prevent Corrosion of System Components

Improves System Efficiency

Made in USA

The PA404A is a Pressure Actuated High Limit, Safety Control for Steam Heating Boilers

It Breaks an Electrical Circuit to Shut Down the Burner if Steam Pressure Rises Above a Safe Level

The PA404B is Used with Suspension-Type Unit Heaters to Make the Fan Circuit When a Pressure Rise Indicates the Presence of Steam

Each Model Contains an SPST Micro Switch Snap Acting Switch

Sensitive Pressure-Actuated Diaphragm Expands or Contracts with Pressure Variations, Moving a Lever Mechanism Which Operates the Snap Switch

A Screw on Top of the Case Allows Set Point Adjustment without Removing the Cover

Differential is Adjusted by Means of a Dial Located Inside the Case

Immersion Type Controllers that Combine High Limit Protection with Switching Relay Control of Burner and Circulator Motors

High Limit Opens Burner Circuit Only

Select Models Include Transformer and Accessory Terminals for Adding a Remote Low Limit Controller

Case Available for Horizontal or Vertical Mounting

Requires a 24 Volt AC Thermostat with Heat Anticipator Set at 0.2 Ampere

Trade Line Models Include Well Adapter, Tube of Heat Conductive Compound and Range Stops

Immersion Type Controllers that Combine High Limit Protection with Switching Relay Control of Burner and Circulator Motors

High Limit Opens Burner Circuit Only

Select Models Include Transformer and Accessory Terminals for Adding a Remote Low Limit Controller

Immersion Type Controllers that Combine High Limit Protection with Switching Relay Control of Burner and Circulator Motors

High Limit Opens Burner Circuit Only

Select Models Include Transformer and Accessory Terminals for Adding a Remote Low Limit Controller

Case Available for Horizontal or Vertical Mounting

Requires a 24 Volt AC Thermostat with Heat Anticipator Set at 0.2 Ampere

Trade Line Models Include Well Adapter, Tube of Heat Conductive Compound and Range Stops