SPX HANKISON HIT 75 - User Manual

Questions and Answers

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gina73Aug 20, 2025
Why is there a high pressure drop across my SPX Dehumidifier?
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  Ryan MarquezAug 20, 2025
  A high pressure drop across your SPX Dehumidifier can be caused by: * A clogged inlet air strainer: Clean the inlet air strainer. * Excessive air flow: Check the flow rate. * A clogged separator filter: Replace the filter sleeve.
T
Toni HarrisAug 29, 2025
What to do if the refrigeration system is not functioning properly on my SPX HANKISON HIT 75 Dehumidifier?
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  nathanfreemanAug 29, 2025
  If the refrigeration system of your SPX Dehumidifier isn't functioning properly, it could be due to: * Power failure: Check the power to the unit. * Open line disconnect switch: Close the disconnect switch. * Blown fuses or open breaker: Check for continuity. * Faulty wiring or loose terminals: Have an electrician check the electrical connections. * High or low ambient conditions: Check the minimum/maximum temperature ranges. * Clogged ambient air filter: Clean the ambient air filter. * Clogged condenser fins: Clean the condenser. * Fan motor or fan control switch malfunction: Replace the fan motor or fan control switch. * Low voltage: Check the wiring.
J
John KlineNov 9, 2025
What to do if there is water downstream of my SPX HANKISON HIT 75 Dehumidifier?
- M
  Michael OrtizNov 9, 2025
  If there's water downstream of your SPX Dehumidifier, it could be due to several reasons: * Residual moisture in downstream pipelines: Blow out the system with dry air. * Open air bypass system: Check the valve positions. * Reversed inlet and outlet connections: Ensure correct connections. * Low temperatures around downstream air lines: Insulate or heat trace air lines exposed to low ambients, or use dry air to lower the dew point. * Excessive moisture at the dryer inlet: Install a separator ahead of the dryer. * Condensate not draining automatically: Replace the drain mechanism if it's not working. * Restricted or frozen drain line: Open the drain line. * Dryer overload: Check the inlet air temperature, pressure, flow rate (compressor capacity), and ambient air temperatur...

Summary

General Safety Information

Pressurized Devices Safety

Safety precautions for devices operating under pressure.

Electrical Safety Guidelines

Electrical safety guidelines for installation and service.

Breathing Air Quality

Air quality considerations for breathing applications.

Installation Procedures

Location Selection

Guidance on selecting the proper installation location.

Piping Connections

Instructions for connecting air inlet, outlet, and bypass piping.

Summary

General Safety Information

Pressurized Devices Safety

Safety precautions for devices operating under pressure.

Electrical Safety Guidelines

Electrical safety guidelines for installation and service.

Breathing Air Quality

Air quality considerations for breathing applications.

Installation Procedures

Location Selection

Guidance on selecting the proper installation location.

Piping Connections

Instructions for connecting air inlet, outlet, and bypass piping.

The Hankison HIT Series refrigerated compressed air dryer is designed for high inlet temperature applications, providing dry, refrigerated compressed air. This instruction manual outlines its installation, operation, and maintenance, ensuring optimal performance and longevity.

Function Description

The primary function of the Hankison HIT Series dryer is to remove moisture from compressed air, preventing condensation and its associated problems in downstream air systems. It achieves this through a refrigeration process that cools the incoming compressed air, causing water vapor to condense into liquid. This liquid condensate is then separated and discharged from the system. The dryer is specifically designed to handle high inlet air temperatures, making it suitable for applications where the compressed air comes directly from a compressor without an aftercooler, or where an aftercooler is installed but the air temperature remains elevated. The unit is equipped with a hermetic, rotary, permanent split capacitor compressor, which is the core of its refrigeration system. The system also includes a condenser, a hot gas by-pass valve, and a filter/dryer to ensure efficient and reliable operation.

Usage Features

The Hankison HIT Series dryer is designed for straightforward usage with several key features to facilitate operation:

Start-up: To initiate operation, the user simply pushes the on/off switch to the "ON" position (marked "I"). A fault light may illuminate briefly during start-up but should extinguish within approximately 5 minutes. If the light remains on for 30 minutes or more, or illuminates after going out, the troubleshooting guide should be consulted.
Operating Check Points: Regular checks are recommended to ensure proper functioning. These include verifying that the rocker switch is in the "ON" position, the amber fault light is off, and condensate is being regularly discharged.
Pressure and Temperature Ranges: The dryer operates within specific minimum and maximum air pressure limits of 20/250 psig (1.4/17.6 kgf/cm²). It can handle a maximum inlet air temperature of 180°F (82°C) and is designed for ambient temperatures between 35/110°F (2/43°C).
Installation Flexibility: The dryer is suitable for both floor and shelf mounting. Proper location is crucial, ensuring the air compressor intake does not draw contaminants into the air system and that there is adequate free air flow around the cabinet. Minimum installation clearances of 36 inches from the wall, 6 inches from the side, and 12 inches from the front are specified.
Piping Connections: The unit requires an air inlet connection from the air compressor, utilizing a supplied strainer to prevent debris from entering the dryer. The strainer should be installed prior to the dryer inlet, observing the flow direction arrows, and in an easily accessible location for cleaning. If vibration is present in the air line, a vibration dampener should be used. The air outlet connects to downstream air lines. For servicing without interrupting air supply, by-pass piping with isolation valves is recommended. Condensate drain outlets should be connected to a drainage system, and the drain line should be anchored to prevent whipping due to system pressure discharge.
Electrical Connections: The dryer operates on the power supply voltage listed on its serial number tag. It comes with an electrical cord for installation into a receptacle of the proper voltage. For models 50 and 75 (115V only), a 20-amp rated receptacle and plug are supplied. It is important to note that the refrigeration system is designed for continuous operation and should not be wired to cycle on/off with the air compressor.
Maximum Flow Capacity: The manual provides detailed tables outlining the maximum flow capacity in scfm (m³/min) for various inlet pressures and operating conditions, both with and without an upstream aftercooler, and for 60 Hz and 50 Hz electrical supplies. These tables allow users to determine the appropriate dryer model for their specific system requirements.

Maintenance Features

To ensure the continued efficient and reliable operation of the Hankison HIT Series dryer, regular maintenance is essential. The manual outlines several key maintenance procedures:

Depressurization Warning: A critical safety caution emphasizes that the dryer is a pressure-containing device and must be depressurized before any servicing.
Ambient Air Filter Cleaning: The ambient air filter should be cleaned monthly, or more frequently if air flow across the condenser is impeded by accumulated dust and dirt. This involves removing the top panel, sliding the filter upwards to remove it, washing it with soap and water, allowing it to dry, and then reinstalling it along with the top panel. Solvents should not be used for cleaning.
Inlet Strainer Cleaning: The inlet strainer should also be cleaned monthly, or more often if rapid clogging occurs. This procedure requires shutting off the compressed air supply to the strainer and depressurizing it. The screen can then be removed, cleaned or replaced, and reinstalled.
Separator/Filter Element Replacement: The separator/filter element should be replaced yearly, or more often if excessive pressure drop occurs across the dryer. This process involves shutting off and depressurizing the compressed air supply, removing the top panel, side panel, and disconnecting the drain tube from the bulkhead fitting. The bowl is then removed by pushing it up, turning it 1/8th turn to the left, and pulling it straight down. The filter bowl should be cleaned.
- Replacing Complete Element: The old element is pulled off and discarded. A new element is pushed onto the filter head, ensuring the O-ring inside the top is in place.
- Replacing Sleeve Only: The element is pulled straight down. The bolt and bottom cap are removed to access the disposable filter sleeve. The separator core can be cleaned with soap and water if needed. A new filter sleeve is slid over the separator core, and the bottom cap and bolt are replaced, hand-tightening the bolt. The O-ring inside the top of the element must be in place before pushing the element onto the filter head.
- After element replacement, the bowl is reassembled to the head, ensuring the O-ring and wave spring are in place and generously lubricated, with wave spring ends pointed down to prevent interference. The drain tube is reconnected, and the side and top panels are reinstalled before repressurizing the dryer.
Automatic Condensate Drain Maintenance: The automatic drain should be checked daily to ensure it is discharging properly. The drain mechanism itself should be replaced yearly. The replacement procedure is similar to the separator/filter element replacement, involving depressurizing the dryer, removing panels and the drain tube, and then removing the old drain mechanism by turning the knurled fitting clockwise. A new mechanism is installed, using a wire or pencil to guide it if necessary. The drain tube fitting is reassembled to the bowl, and the bowl to the head, ensuring the large O-ring is in place. The drain tube is reconnected to the bulkhead fitting, and panels are reinstalled before repressurizing.
Troubleshooting Guide: The manual includes a comprehensive troubleshooting guide to assist users in diagnosing and resolving common issues such as water downstream of the dryer, high pressure drop, fault alarms, and refrigeration system malfunctions. This guide provides possible causes and corrective actions, ranging from cleaning components to contacting qualified service personnel.
Maintenance Kits: Specific maintenance kits (HITFMK1, HITFMK2, HITFMK3, HITFMK4) are available for different dryer models, containing essential replacement parts such as the separator/filter cartridge, drain mechanism, O-ring for the bowl, and ambient air filter. Items included in these kits are marked with an asterisk in the parts list.