Lennox SLP99UH070XV36B User Manual

Page 1
© 2020 Lennox Industries Inc.
100001
10/2020
SLP99UHV
Service Literature
SLP99UHV SERIES UNITS
SLP99UHV series units are high-efficiency upflow, horizon
tal right and left) gas furnaces equipped with variable ca
pacity gas valve, variable speed combustion air inducer and
variable speed indoor blower motor. All models are de
signed only for direct vent (dual pipe) venting system.
SLP99UHV units are available in heating capacities from
66,000 to 132,000 Btuh (19.3 to 38.6 kW) and cooling ap
plications from 2 to 5 tons (7.0 kW to 17.5 kW). Refer to En
gineering Handbook for proper sizing.
Units are factory-equipped for use with natural gas. Kits are
available for conversion to LPG operation. SLP99UHV mod
els include a SureLight
®
variable capacity integrated control
that can be used with a Lennox communicating thermostat
as part of a communicating comfort system. All SLP99UHV
units meet the California Nitrogen Oxides (NO
x
) Standards
and California Seasonal Efficiency requirements.
All specifications in this manual are subject to change. Pro
cedures outlined in this manual are presented as recom
mendations only and do not supersede or replace local or
state codes. In the absence of local or state codes, the
guidelines and procedures outlined in this manual (except
where noted) are recommendations only and do not consti
tute code.
TABLE OF CONTENTS
Specifications Page 2.............................
Optional Accessories Page 3......................
Blower Data Page 4..............................
I Unit Components Page 20.......................
II Communicating Thermostat Page 44..............
III Placement and Installation Page 47..............
IV Start Up Page 63..............................
V Heating System Service Checks Page 60..........
VI Typical Operating Characteristics Page 69........
VII Maintenance Page 70..........................
VIII Wiring and Sequence of Operation Page 73.....
XI Field Wiring Page 81..........................
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, person
al injury or loss of life. Installation and service must
be performed by a licensed professional HVAC in
staller (or equivalent), service agency or the gas sup
plier.
WARNING
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at discon
nect switch(es). Unit may have multiple
power supplies.
CAUTION
As with any mechanical equipment, contact with
sharp sheet metal edges can result in personal injury.
Take care while handling this equipment and wear
gloves and protective clothing.

Lennox SLP99UH070XV36B Specifications

General

Brand	Lennox
Model	SLP99UH070XV36B
Category	Furnace
Language	English

Summary

SLP99UHV SERIES UNITS

Specifications

Detailed technical specifications for the SLP99UHV series.

OPTIONAL ACCESSORIES - ORDER SEPARATELY

BLOWER DATA

SLP99UHV PARTS ARRANGEMENT

I-UNIT COMPONENTS

Detailed breakdown of the furnace unit's components.

SLP99UHV INTEGRATED CONTROL CONFIGURATION GUIDE

THERMOSTAT SELECTION

Guide for selecting thermostat operation modes.

COOLING MODE BLOWER SPEED

Configuration settings for cooling blower speeds.

HEATING BLOWER-OFF DELAY

Settings for the blower's off delay in heating mode.

Diagnostic LED (Figure 4)

Error Code Recall Mode

Procedure to recall and clear diagnostic error codes.

Field Test Mode

Mode for system testing and diagnostics.

Configuring Unit Size Codes

UNIT SIZE CODE

Reference table for furnace model and capacity size codes.

LED 7 Segment Status / Error Code

Integrated Control Diagnostic Codes (continued)

OPERATING SEQUENCE

NO CALL FOR DEHUMIDIFICATION

Operating sequence when no dehumidification is called.

BASIC MODE (only active on a Y1 thermostat demand)

Basic operation mode for Y1 thermostat demand.

PRECISION MODE (operates independent of a Y1 thermostat demand)

Precision mode for independent Y1 thermostat operation.

B-Blower Compartment (Figure 7)

1. Blower Motor (B3)

Description and identification of the blower motor.

Troubleshooting Motor Windings

TEST A

Procedure for testing motor winding resistance to ground.

TEST B

Procedure for testing motor phase-to-phase resistance.

C-Heating Components

1. Ignitor

Description of the SureLight® ignitor.

2. Flame Sensor

Location and function of the flame sensor.

3. Flame Rollout Switches

Description of the flame rollout safety switches.

5. Duralock Plus™ Heat Exchanger (Figure 15)

Description of the heat exchanger assembly.

Vent Calibration

Measuring pressure differential Figure 18

Procedure for measuring pressure differential.

Measuring Pressure Differential

II-Communicating Thermostat (if applicable)

Communicating Enabled Furnace and Non-Communicating Outdoor Unit

Wiring diagram for communicating furnace with non-communicating outdoor unit.

Communicating Enabled Furnace and Communicating Enabled Outdoor Unit

Wiring diagram for communicating furnace and outdoor unit.

Optional Accessories for use with any Communicating System

III-PLACEMENT AND INSTALLATION

Pipe & Fittings Specifications

Specifications for approved piping and fitting materials.

PRIMER & SOLVENT CEMENT

Specifications for primer and solvent cement.

CANADA PIPE & FITTING & SOLVENT CEMENT

Specifications for Canadian pipe and fittings.

OUTDOOR TERMINATION USAGE*

Joint Cementing Procedure

Procedure for cementing pipe joints.

Venting Practices

Piping Suspension Guidelines

Guidelines for supporting vent piping.

Wall Thickness Guidelines

Guidelines for wall thickness related to vent installations.

Exhaust Piping (Figures 26, 27 and 28)

Details on exhaust piping installation.

Intake Piping (Figures 27 and 28)

Details on intake piping installation.

Vent Piping Guidelines

General guidelines for vent piping installation.

Maximum Allowable Intake or Exhaust Vent Length in Feet

VENT TERMINATION CLEARANCES

US Installations1

Vent termination clearance requirements for USA installations.

Canadian Installations2

Vent termination clearance requirements for Canadian installations.

General Guidelines for Vent Terminations

Maximum Allowable Vent Pipe Length (in ft.3) Without Insulation In Unconditioned Space For Winter Design Temperatures Modulating High Efficiency Furnace

Table for maximum vent pipe lengths based on temperature and insulation.

Details of Intake and Exhaust Piping Terminations for Direct Vent Installations

EXHAUST PIPE TERMINATION SIZE REDUCTION

Table for reducing exhaust pipe size at termination.

FIELD FABRICATED WALL TERMINATION

STRAIGHT APPPLICATION

Details for straight wall termination.

EXTENDED APPLICATION

Details for extended wall termination.

ALTERNATE TERMINATIONS (TEE & FORTY-FIVE DEGREE ELBOWS ONLY)

Alternate wall termination methods using elbows.

Condensate Piping

CONDENSATE TRAP AND PLUG LOCATIONS

Location of condensate trap and plug for upflow units.

TRAP / DRAIN ASSEMBLY USING 1/2" PVC OR 3/4" PVC

Optional Condensate Drain Connection

Details for optional condensate drain connection.

Optional Drain Piping From Trap

Details for optional drain piping from the trap.

Drain Assembly for 1/2 inch Drain Pipe

Assembly instructions for 1/2 inch drain pipe.

Drain Assembly for 3/4 inch Drain Pipe

Assembly instructions for 3/4 inch drain pipe.

Drain Trap Assembly with 1/2 inch Piping

Assembly of the drain trap with 1/2 inch piping.

Drain Trap Assembly with 3/4 inch Piping

Assembly of the drain trap with 3/4 inch piping.

IV-START-UP

A-Preliminary and Seasonal Checks

Checks to perform before unit operation.

B-Heating Start-Up

Procedure for starting the heating cycle.

Priming Condensate Trap

Procedure to prime the condensate trap.

Gas Valve Operation (Figure 49)

Instructions for operating the gas valve.

V-HEATING SYSTEM SERVICE CHECKS

C-Testing Gas Piping

Procedure for testing gas piping connections.

D-Testing Gas Supply Pressure

Procedure for testing gas supply pressure.

MANIFOLD PRESSURE MEASUREMENT

Operating Signal (Delta P) Measurement

H- Proper Combustion

I- High Altitude

J- Proper Ground and Voltage

VI-TYPICAL OPERATING CHARACTERISTICS

A-Blower Operation and Adjustment

Details on blower operation and adjustment.

B-Temperature Rise

Information on measuring temperature rise.

C-External Static Pressure

Procedure for measuring external static pressure.

D-Discharge Air Temperature Sensor

Description of the discharge air temperature sensor.

VII-MAINTENANCE

Blower

Maintenance procedures for the blower motor.

Filters

Maintenance and replacement guidelines for filters.

Discharge Air Temperature Sensor Location

Location of the discharge air temperature sensor.

Discharge Air Temperature Sensor Wiring

Wiring details for the discharge air temperature sensor.

Cleaning the Burner Assembly

VIII- Wiring and Sequence of Operation

Applications Using a Two-Stage Thermostat

Heating sequence for two-stage thermostat applications.

Applications Using a Single-Stage Thermostat

Heating sequence for single-stage thermostat applications.

A - Sequence of Operation and Troubleshooting Flow Chart

IGNITION AND CALL FOR LOW FIRE WITH TWO-STAGE THERMOSTAT

Flow chart for ignition and low fire sequence with two-stage thermostat.

CALL FOR HIGH FIRE WITH TWO-STAGE THERMOSTAT

CALL FOR HEAT SATISFIED

IGNITION AND CALL FOR LOW FIRE WITH SINGLE-STAGE THERMOSTAT

CALL FOR COOLING

CONTINUOUS LOW SPEED INDOOR BLOWER SEQUENCE OF OPERATION

IX- Field Wiring

Field Wiring for Non-Communicating Thermostat Applications

Wiring instructions for non-communicating thermostats.

Field Wiring for Non-Communicating Thermostat Applications (Continued)