CAMBRIDGE M-SERIES - User Manual

M-SERIES
DRAW THRU
DIRECT GAS-FIRED
MAKE-UP AIR HEATERS
TECHNICAL MANUAL
M-TM1-0915
M110-M115 (3HP) REV. G
M115 (5HP) REV. H
M118-M136 REV. C
M140 REV. A
mWARNING:
Improper installation, adjustment, alteration, service or maintenance can cause property dam-
age, injury or death. Read the installation, operating, and maintenance instructions thoroughly
before installing or servicing this equipment.
FOR YOUR SAFETY
The use and storage of gasoline or other flammable vapors and liquids in open containers in
the vicinity of this appliance is hazardous.
FOR YOUR SAFETY
If you smell gas:
1. Open windows.
2. Don’t touch electrical switches.
3. Extinguish any open flame.
4. Immediately call your gas supplier.
Made in the USA
®
90.1
ASHRAE
ASHRAE
COMPLIANT
COMPLIANT
®

Summary

HAZARD SUMMARY

Hazard Identification

Identifies warnings and cautions throughout the manual.

TYPICAL SYSTEM OVERVIEW

Control Systems Overview

Describes different control systems like Maxitrol Series 14 and 44.

ACCESSORY IDENTIFICATION

Component Identification

Identifies various components of the heater and its configurations.

HEATER; ACCESSORY WEIGHTS

Horizontal Mount Weights

Lists weights of base heaters and accessories for horizontal mount.

Vertical Mount Weights

Lists weights of base heaters and accessories for vertical mount.

HEATER OPERATION AND CONFIGURATION

Heater Operation

Explains how the draw-thru heaters operate and their basic functions.

Heater Configuration

Illustrates the internal components and configuration of the heater.

INSTALLATION INSTRUCTIONS

Uncrating Instructions

Steps for uncrating the equipment, checking for damage, and verifying items.

Mounting Location Selection

Guidelines for selecting an appropriate and accessible mounting location.

HORIZONTAL MOUNT - MOUNTING CURB

Mounting Curb Installation

Instructions and dimensions for installing the mounting curb for roof top configuration.

HORIZONTAL MOUNT - ROOF TOP CONFIGURATION

Roof Top Installation Preparation

Steps and warnings for preparing the roof for heater installation.

TYPICAL INSTALLATION - ROOF TOP

Roof Opening Dimensions M110-M115

Shows typical roof opening dimensions for models M110-M115.

TYPICAL INSTALLATION - ROOF TOP

Roof Opening Dimensions M118-M136

Shows typical roof opening dimensions for models M118-M136.

TYPICAL INSTALLATION - ROOF TOP

Roof Opening Dimensions M140

Shows typical roof opening dimensions for model M140.

HORIZONTAL MOUNT - OUTDOOR PAD MOUNT CONFIGURATION

Pad Mount Installation Steps

Detailed steps for installing the heater on an outdoor pad mount.

TYPICAL INSTALLATION - OUTDOOR PAD MOUNT

Wall Opening Dimensions M118-M136

Shows typical wall opening dimensions for pad mount models M118-M136.

TYPICAL INSTALLATION - OUTDOOR PAD MOUNT

Wall Opening Dimensions M140

Shows typical wall opening dimensions for pad mount model M140.

HORIZONTAL MOUNT - THRU WALL CONFIGURATION

Thru Wall Installation Steps

Detailed steps for installing the heater through a wall.

TYPICAL INSTALLATION - THRU WALL

Wall Opening Dimensions M110-M115

Shows typical wall opening dimensions for thru wall models M110-M115.

TYPICAL INSTALLATION - THRU WALL

Wall Opening Dimensions M118-M136

Shows typical wall opening dimensions for thru wall models M118-M136.

VERTICAL MOUNT - OUTDOOR CONFIGURATION

Outdoor Vertical Installation Steps

Detailed steps for installing the heater in a vertical outdoor configuration.

TYPICAL INSTALLATION - VERTICAL MOUNT OUTDOOR

Wall Opening Dimensions M118-M136

Shows wall opening dimensions for vertical outdoor horizontal blast models.

TYPICAL INSTALLATION - VERTICAL MOUNT OUTDOOR

Wall Opening Dimensions Up Blast M118-M136

Shows wall opening dimensions for vertical outdoor up blast models.

VERTICAL MOUNT - INDOOR CONFIGURATION

Indoor Vertical Installation Steps

Detailed steps for installing the heater in a vertical indoor configuration.

TYPICAL INSTALLATION - VERTICAL MOUNT INDOOR

Wall Opening Dimensions M118-M136

Shows wall opening dimensions for vertical indoor horizontal blast models.

INSTALLATION INSTRUCTIONS - GAS PIPING

Gas Piping Procedures

Details requirements and procedures for gas piping installation and safety.

INSTALLATION INSTRUCTIONS - ELECTRICAL

Electrical Installation Procedures

Outlines voltage, amperage, grounding, and wiring requirements for electrical connections.

START-UP INSTRUCTIONS

Visual Inspection of Equipment

Checks for physical damage, accessory installation, and loose components.

Electrical Supply Voltage Verification

Verifies the electrical supply voltage matches the nameplate requirements.

START-UP INSTRUCTIONS

Gas Supply Pressure Verification

Confirms the gas supply pressure meets the heater's nameplate requirements.

Blower Rotation Check

Instructions to verify the blower motor is rotating in the correct direction.

Burner Profile Damper Pressure Drop Check

Checks the pressure drop across the burner profile plate for proper operation.

START-UP INSTRUCTIONS

Motor Amp Draw Check

Measures motor current to ensure it does not exceed nameplate FLA.

Calculating and Adjusting Burner Manifold Pressure

Procedures for calculating and adjusting the burner manifold pressure.

START-UP INSTRUCTIONS

Gas Valve Leak Check

Procedures for checking the gas valve seat for leaks using a manometer.

START-UP INSTRUCTIONS

Gas Train Leak Check

Instructions for checking the gas train and connections for leaks.

Minimum Fire Setting

Procedure for setting the minimum fire flame signal for proper burner operation.

START-UP INSTRUCTIONS

Low Fire Start Adjustment

Details on adjusting the low fire start control for initial firing rate.

Preliminary Remote Control Station Operational Check

Checks the functionality of the remote control station before final setup.

START-UP INSTRUCTIONS

Final Heater Preparation

Final checks and preparations before operating the heater.

Final Remote Control Station Check

Final verification of the remote control station settings and operation.

SHUT-DOWN INSTRUCTIONS

Shutdown Procedures

Steps for safely shutting down the heater and its components.

OPERATING INSTRUCTIONS

Operating Sequence

Describes the step-by-step sequence for summer ventilation and heating modes.

OPERATING INSTRUCTIONS

Electronic Thermostat (OET) Operation

Explains the features and operation of the electronic thermostat.

SETTING TEMPERATURES

Setting Heater Temperatures

How to set the HEAT ON and HEAT OFF temperatures for the thermostat.

TEMPERATURE CALIBRATION

Calibrating the Electronic Thermostat

Procedure to compensate for lead wire resistance and adjust temperature readings.

OPERATING INSTRUCTIONS

TSS Controller Overview

Details the features and capabilities of the TSS programmable controller.

SETTING CURRENT DAY OF WEEK, TIME, MONTH;DAY, AND YEAR

Setting Clock and Date

Instructions for setting the controller's internal clock and calendar.

SETTING AUTOMATIC ADJUSTMENT FOR DAYLIGHT SAVING TIME

Daylight Saving Time Setting

How to configure the controller for automatic daylight saving time adjustments.

SETTING TEMPERATURES

TSS Heating Mode Temperatures

Setting HEAT ON and HEAT OFF temperatures for the TSS controller.

TSS Setback Mode Temperatures

Setting temperatures for the SETBACK mode in the TSS controller.

SETBACK OVERRIDE

Using the TSS Override Timer

How to use the override timer for temporary heating.

SETTING SCHEDULES

Programming Heating Schedules

Instructions for programming daily ON/OFF schedules for heating mode.

Programming Ventilation Schedules

Instructions for programming daily ON/OFF schedules for summer ventilation mode.

PROGRAMMING THE TSS CONTROLLER

Setting Monday-Friday Schedules

Steps to set the ON and OFF times for Monday through Friday.

Programming Subsequent Cycles

Instructions for programming additional ON/OFF cycles for specific days.

HOLIDAY SETBACK SCHEDULE

Scheduling Holiday Periods

How to program up to nine holiday periods to override normal schedules.

MAINTENANCE INSTRUCTIONS

Blower Bearing Lubrication

Recommended lubrication intervals and types for blower bearings.

Motor Bearing Lubrication

Recommended greases for motor bearings.

Belt Tensioning Procedures

Procedures and specifications for checking and adjusting belt tension.

MAINTENANCE INSTRUCTIONS

ASCO Gas Valves Cleaning

Steps for disassembling and cleaning ASCO gas valves.

Ordering Information for ASCO Rebuild Kits

Guidance on ordering specific rebuild kits for ASCO valves.

Gas Train Leak Check

Procedures for periodically checking the gas train for leaks.

MAINTENANCE INSTRUCTIONS

Burner Cleaning

Recommended procedures for cleaning the burner if application is very dirty.

Gas Valve Cleaning

When and how to clean gas valves based on observed operation.

FILTERS

Filter Types

Describes different types of filters used in the heaters.

Filter Cleaning and Replacement

Instructions for cleaning permanent filters and replacing disposable filters.

REFERENCE

Electrical Control Enclosure Isometric Drawing M110-M115

Diagram showing components within the electrical enclosure for specific models.

REFERENCE

Electrical Control Enclosure Isometric Drawing M118-M136

Diagram showing components within the electrical enclosure for specific models.

REFERENCE

Electrical Control Enclosure Isometric Drawing M140

Diagram showing components within the electrical enclosure for model M140.

REFERENCE

Electrical Wiring Diagrams Series 14

Provides the electrical wiring diagram for Series 14 controls.

REFERENCE

Electrical Wiring Diagrams Series 44

Provides electrical wiring diagrams for Series 44 controls.

REFERENCE

Electrical Wiring Diagrams Series 44 (Tamperproof Controls)

Wiring diagram for Series 44 controls with tamperproof features.

REFERENCE

Electrical Wiring Diagrams Series 44 (Temperature Setback System)

Wiring diagram for Series 44 controls with temperature setback system.

GAS CONTROL SYSTEMS

Maxitrol Series 14 Controls

Describes the function of Maxitrol Series 14 electronic discharge temperature controls.

Maxitrol Series 44 Controls

Describes the function of Maxitrol Series 44 constant space temperature controls.

Intermittent;Continuous Control

Explains how the burner input is modulated for different operating modes.

REMOTE CONTROL STATION COMPONENTS

Remote Control Station Description

Details the components and function of the remote control station.

Maxitrol Series 14 Remote Heat Adjustment

Information on the remote heat adjust dial for Series 14 controls.

Maxitrol 14 Space Temperature Override

How the Series 14 system uses a space thermostat for temperature override.

INDIVIDUAL HEATER COMPONENT DESCRIPTIONS

Air Flow Switches

Explains the function of high and low air flow switches and their settings.

Amplifier Description

Describes the amplifier's role in driving the gas valve for temperature control.

Convenience Outlet

Information about the provided convenience outlet within the electrical enclosure.

INDIVIDUAL HEATER COMPONENT DESCRIPTIONS

Damper Motor

Details the damper motor operation and adjustment.

Discharge Temperature Sensor

Explains the function of the discharge temperature sensor.

Disconnect Switch

Description of the non-fused disconnect switch and its safety features.

Exhaust Fan Contact

How the exhaust fan contact interlocks with the heater.

Flame Safeguard Relay

Explains the function of the flame safeguard relay in ensuring burner ignition.

Flame Rod

Describes the flame rod's role in sensing flame presence.

Fuse Block

Explains the fuse block's purpose for branch circuit protection.

High Gas Pressure Switch

Details the high gas pressure switch as a safety lockout device.

High Pressure Regulator

Explains the requirement and function of the high pressure regulator.

INDIVIDUAL HEATER COMPONENT DESCRIPTIONS

High Temperature Limit

Describes the high temperature limit and its manual reset function.

Inclined Manometer

Explains the use of the manometer for setting burner profile plate pressure drop.

Differential Pressure Switch;Gauge

Details the differential pressure switch for automatic profile adjustment.

Igniter

Information about the hot surface igniter's function and fragility.

Interior Light(s)

Notes on interior lights within the heater and enclosures.

Leak Test Facility

Describes the leak test facility for safety shut-off valves.

Modulating Valve

Explains the modulating valve's response to control signals and adjustment screws.

Combination Valve

Describes the combination valve serving as a regulator and shut-off.

Manifold Pressure Regulator

Explains the function of the manifold pressure regulator.

INDIVIDUAL HEATER COMPONENT DESCRIPTIONS

Motor Starter, Overload, & Auxiliary Contact

Details the components of the motor starter assembly.

Multi-Functional PC Board

Explains the five functions of the PC board for control systems.

Service Switch

Describes the service switches for local or remote control.

Space Temperature Selector

Explains how the space temperature selector controls heater output.

Transformer

Information on the dual voltage transformer and its secondary voltages.

DAMPER MOTOR REPLACEMENT & ADJUSTMENT

Damper Motor Replacement Procedure

Step-by-step instructions for replacing the damper motor.

Damper Motor Adjustment

How to adjust the damper motor cams and linkage for proper operation.

GAS TRAIN DRAWINGS

Vertical Mount Gas Train

Illustrates the gas train components for vertical mount configurations.

Horizontal Mount Gas Train

Illustrates the gas train components for horizontal mount configurations.

TROUBLESHOOTING GUIDE

No Blower Operation

Lists common causes and corrective actions for the blower not operating.

TROUBLESHOOTING GUIDE

Blower Runs, No Heat, Safety Relay Doesnt Lock Out

Addresses issues where the blower runs but the unit doesn't heat, and the safety relay is not tripped.

Blower Runs, No Heat, Safety Relay Locks Out

Addresses issues where the blower runs, no heat occurs, and the safety relay trips.

TROUBLESHOOTING GUIDE

Blower Runs, Unit Heats, Short Cycles Without Resetting

Troubleshooting for short cycling when the unit heats.

TROUBLESHOOTING GUIDE

High Limit Tripped

Addresses causes and solutions for the high limit switch tripping.

Blower Runs, Unit Heats, Will Not Cycle Off

Troubleshooting for when the unit runs continuously without cycling off.

Modulating Valve Does Not Modulate; Continuous High Fire

Addresses issues where the modulating valve fails to adjust output.

TROUBLESHOOTING GUIDE

Modulating Valve Does Not Modulate; Continuous High Fire (Continued)

Continues troubleshooting for modulating valve issues.

Erratic or Pulsating Flame

Addresses problems with an erratic or pulsating flame.

TROUBLESHOOTING GUIDE

Erratic or Pulsating Flame (Continued)

Continues troubleshooting for erratic or pulsating flame issues.

ANSI;ASHRAE;IESNA STANDARD 90.1

Standard Overview and Purpose

Provides an overview and purpose of ASHRAE Standard 90.1.

Compliance Requirements

Lists requirements for Cambridge heaters to comply with Standard 90.1.

MAINTENANCE LOG

Maintenance Log Entries

A log for recording maintenance activities and dates.

CAMBRIDGE M-SERIES Specifications

General

Brand	CAMBRIDGE
Model	M-SERIES
Category	Heater
Language	English