WABCO SYSTEM SAVER HP MM1736

Questions and Answers

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Frederick JonesAug 17, 2025
What to do if WABCO SYSTEM SAVER HP MM1736 leaks from purge valve during compressor loaded cycle?
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  whitepaigeAug 17, 2025
  If the WABCO Dehumidifier is leaking from the purge valve during the compressor loaded cycle, it may be caused by debris under the purge valve seat, such as particles from fittings or the air inlet line. To resolve this, remove the purge valve cartridge and inspect for contamination. Remove any contamination if possible, or replace the purge valve cartridge. Also, remove the desiccant cartridge and clean the sump area.
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Cassandra LewisAug 20, 2025
Why WABCO SYSTEM SAVER HP MM1736 Dehumidifier does not purge when compressor unloads?
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  Jessica SinghAug 20, 2025
  If the WABCO Dehumidifier isn't purging when the compressor unloads, it could be due to a purge valve stuck closed. In this case, replace the purge valve. Alternatively, the air governor may not be working correctly; inspect it and repair or replace it per instructions. It's also possible that the cut-out pressure is never achieved by the air compressor. Check for air leaks in the system and repair as needed. If there are no leaks, check the compressor output and repair or replace it per the manufacturer’s instructions.
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owellsAug 23, 2025
Why WABCO Dehumidifier purges too often?
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  calderonscottAug 23, 2025
  If the WABCO Dehumidifier is purging too often, accompanied by excessive cycling of the compressor, there could be several reasons. There may be a leak in the line between the compressor and dryer port 4, in which case you should repair the air line. Also, the line between the outlet of the dryer and the wet tank should be unobstructed, without a check valve installed. Other potential causes include leaks in the air system (repair the leaks), excessive air system demands (increase air system capacity or reduce air demand), an outlet check valve not seating (inspect and replace the outlet check valve as needed), or leaking air compressor unloaders (inspect the compressor and repair or replace it per the manufacturer’s instructions).
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Eric SolomonAug 26, 2025
How to fix no air pressure build-up in WABCO SYSTEM SAVER HP MM1736 Dehumidifier system?
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  scottmercedesAug 26, 2025
  If there is no air pressure build-up in the WABCO Dehumidifier system, it might be because the air dryer is not plumbed correctly with reversed connections. Ensure the compressor discharge line is plumbed to the air dryer port 1, and the air dryer port 21 or 22 is connected to the vehicle’s supply tank. Another reason could be that the air governor is not working correctly; inspect the governor and replace it, if needed, with a WABCO governor kit. Air system leaks, such as in the compressor discharge line, air dryer, reservoirs, or brake and suspension valves, could also be the cause; locate and repair any leaks. Finally, the air dryer may be leaking from the purge valve; refer to purge valve conditions listed in this chart.
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Sandra BlevinsAug 28, 2025
How to thaw WABCO SYSTEM SAVER HP MM1736 Dehumidifier frozen with water?
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  Matthew HallAug 28, 2025
  If the WABCO Dehumidifier is frozen with water collecting in the base, it could be due to no electrical power to the heater connector. Check for a blown fuse and repair the heater circuit, noting that there must be power to the heater connector the entire time the vehicle’s ignition is ON. Another cause might be low voltage to the heater connector; repair the cause of low voltage, such as a poor electrical ground, bad connections, or corroded wire splices. Alternatively, the heater assembly itself may not be working, in which case you should replace it. Finally, ensure the correct voltage air dryer is used; for example, a 12-volt air dryer should not be used in a 24-volt system. If the voltage is incorrect, replace it with the correct voltage air dryer.
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Paula ThompsonAug 30, 2025
Why WABCO Dehumidifier regeneration cycle too long?
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  Michele ColeAug 30, 2025
  If the WABCO Dehumidifier regeneration cycle is too long, accompanied by loss of pressure in the supply tank, the outlet check valve may not be seating properly. Inspect and replace the outlet check valve as needed.
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Tony JohnsonSep 1, 2025
Why WABCO Dehumidifier purge valve is rapidly spitting air?
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  Mrs. Felicia MooreSep 1, 2025
  If the WABCO Dehumidifier has rapid “spitting” of air from the purge valve in small amounts, with the frequency varying with engine speed, it indicates that the compressor is not completely unloading when cut-out pressure is reached. Inspect the compressor and repair or replace it per the manufacturer’s instructions. Also, ensure there are no leaks in the unloader signal line between the compressor and port 4 of the dryer.
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Michael NashSep 4, 2025
Why WABCO SYSTEM SAVER HP MM1736 Dehumidifier regeneration cycle is too short?
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  David BlakeSep 4, 2025
  If the WABCO Dehumidifier regeneration cycle is too short, it may be caused by high air system demands during the compressor unloaded cycle. To resolve this, increase air system capacity or reduce air demands. Another possible cause is the air governor not working correctly. Verify that the dryer governor is operating at correct pressures and that the signal changes levels in one second or less. Replace it if necessary.
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John HuertaSep 6, 2025
What to do if WABCO SYSTEM SAVER HP MM1736 Dehumidifier has no regeneration cycle?
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  Patricia GonzalesSep 6, 2025
  If the WABCO Dehumidifier has no regeneration cycle and no airflow from the purge valve after the initial purge blast, it could be due to reversed air dryer connections at the dryer. Verify correct dryer installation per the system diagram. Another cause might be a blocked or contaminated internal dryer orifice, in which case you should replace the dryer.
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Elizabeth CastroSep 9, 2025
Why air flows out of WABCO SYSTEM SAVER HP MM1736 Dehumidifier purge valve when compressor is unloaded?
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  Alexander WallSep 9, 2025
  If the WABCO air dryers equipped with turbo cut-off valves have air flowing out of the purge valve the entire time the compressor is unloaded, the turbo cut-off valve may not be sealing. In this case, replace the turbo cut-off valve. Another potential cause is the outlet check valve not seating, so replace the outlet check valve.

Summary

General Information

Document Symbols and Usage

Explains document symbols (DANGER, WARNING, CAUTION, NOTICE) and action steps.

Safety Information and Precautions

Safe Work Environment Guidelines

Lists requirements for safe work, use of PPE, and observing hazard alerts.

Introduction to the System Saver HP Air Dryer

System Overview and Identification

Introduces the manual and describes dryer identification and integrated features.

How the Air Dryer Works

Explains the basic principle of compressed air drying and moisture retention.

Air Dryer Cycle Operation

Air Flow During Dryer Cycle

Illustrates air dryer cycle stages and air flow from compressor loading to unloading.

System Saver HP Air Dryer System Diagram

Component Layout and Connections

Details the system diagram, including components and lines for operation.

Air Dryer Component Identification

Exploded View of Dryer Components

Shows an exploded view of the air dryer and its replaceable components.

Dryer Identification Tag and Component Details

Identification Tag Information

Explains the information on the dryer's identification tag and its purpose.

Key Component Descriptions

Describes key components like cartridge, heater, and check valve.

Air Dryer Component Functions

Relief, Purge, Turbo, Heater Functions

Explains functions of pressure relief, purge valve, turbo cut-off valve, and heater harness.

Governor Function and Control

Governor Operation and Purpose

Explains the governor's function in controlling compressor pressure and initiating dryer cycles.

Component Removal and Installation

Requirements for Component Replacement

Lists prerequisites for component replacement, including system checks and draining tanks.

Desiccant Cartridge Replacement Procedure

Steps for Desiccant Cartridge Replacement

Details the procedure for replacing the desiccant cartridge, including part numbers.

Outlet Check Valve Assembly Procedure

Steps for Outlet Check Valve Replacement

Provides step-by-step instructions for removing and installing the outlet check valve assembly.

Heater Assembly Removal and Installation

Steps for Heater Assembly Replacement

Details the procedure for removing and installing the heater assembly.

Turbo Cut-Off Valve and Governor Installation

Turbo Cut-Off Valve Installation Steps

Outlines steps for turbo cut-off valve installation.

Governor Installation and Function

Describes governor installation and its operational function.

Purge Valve and Air Dryer Assembly Replacement

Purge Valve Replacement Procedure

Provides instructions for purge valve replacement.

Air Dryer Assembly Replacement Procedure

Details the procedure for replacing the entire air dryer unit.

Troubleshooting and Maintenance Procedures

Routine Maintenance Schedule and Tips

Lists recommended maintenance actions, intervals, and tips for extreme conditions.

Troubleshooting Common Air Dryer Issues

Identifying and Resolving Dryer Problems

Introduces troubleshooting by referring to Table E for common conditions and solutions.

Diagnostic Tests for Air Dryer Performance

Heater Resistance Testing Procedure

Details the procedure for checking the heater resistance using a volt-ohmmeter.

Electrical Power, Leak, and Pressure Tests

Testing Electric Power and Air Leaks

Explains testing electric power and performing air system leak tests.

Air Pressure and Operational Checks

Details pressure checks and operational tests for loaded/unloaded cycles and regeneration.

Turbo Cut-Off Valve (TCV) Troubleshooting Guide

Testing the Turbo Cut-Off Valve (TCV)

Explains how to test the Turbo Cut-Off Valve (TCV) function on relevant dryer models.

Glossary of Air Dryer System Terms

Application Information and Recommendations

Installation and Operating Environment

Provides recommendations for installation, operating environment parameters, and discharge line requirements.

System Saver Installation Criteria

Key Installation Parameters and Requirements

Outlines installation criteria including pressure requirements, flow capacity, and duty cycle.