KT-976 vs KT-986 Duct Cleaning Machines: How to Choose – Duct Diameter, Function, and Application Comparison

Selection conclusion: The KT-976 is suitable for projects focused on 250–800 mm main duct cleaning where a robot can enter and move inside the duct. The KT-986 is suitable for projects that require cleaning both main ducts and small-diameter branch ducts. The KT-976 is centered on robotic cleaning, while the KT-986 integrates robotic cleaning and flexible shaft cleaning, covering a published applicable duct diameter range of 100–800 mm.

If you primarily undertake large central air conditioning duct cleaning projects, the KT-976 should be evaluated first. If project duct diameters vary widely, duct configurations are complex, and different duct sections require different cleaning methods, the KT-986 should be considered.

1. What Are the KT-976 and KT-986?

KT-976 Central Air Conditioning Duct Cleaning Robot

The KT-976 primarily uses a robot that enters the duct for cleaning. Published documentation indicates an applicable duct diameter of 250–800 mm. It is equipped with a cleaning robot, power unit, and related connection components. Some versions feature 1080P front and rear dual cameras, HD display, remote control, and integrated brushing and vacuuming.

Its main feature is allowing the robot to enter ducts that meet passage conditions, while operators observe the duct interior via video and control the equipment to complete cleaning.

KT-986 Combined Central Air Conditioning Duct Cleaning Machine

The KT-986 uses a combined design integrating a robot and a flexible shaft. The robot mode is used for main ducts suitable for robot entry. The flexible shaft mode uses a rotating brush head to clean applicable duct sections, expanding the equipment's coverage for small-diameter ducts and different duct configurations.

Published documentation indicates that the KT-986 has an overall applicable duct diameter of 100–800 mm, with the robot mode covering 250–800 mm and the flexible shaft mode covering 100–800 mm. It is equipped with a 15 m flexible shaft and video monitoring functions.

The main difference between the two machines is not a simple model upgrade, but the method by which the cleaning tool enters the duct and the equipment's project coverage capability.

2. KT-976 vs KT-986 Main Parameter Comparison

The above are the main differences in published documentation. During actual procurement, the supplier should be asked to confirm the power, weight, brush speed, vacuuming capability, power supply specifications, accessory quantity, and control method of the specific version to avoid mixing parameters between different configurations.

3. What Are the Product Features of the KT-976?

1. Suitable for 250–800 mm main ducts
The KT-976 has a published applicable duct diameter of 250–800 mm, suitable for evaluation in medium-to-large central air conditioning duct cleaning. The prerequisite for using this equipment is that the robot can enter the target duct section and maintain normal movement.

2. Brushing and vacuuming coordination
The equipment uses a combined brushing and vacuuming design. The brush head cleans wall-attached deposits, while the vacuum system collects loosened dust, reducing the risk of contaminants re-dispersing during cleaning.
Actual results are also affected by duct sealing, contaminant type, vacuum system condition, and operating technique.

3. Front and rear cameras for observation
Some KT-976 configurations feature 1080P front and rear dual cameras, which can observe conditions in front of and behind the robot inside the duct and support video recording and photo capture.
Video monitoring helps operators understand equipment position and the cleaning process, and facilitates retention of project video records.

4. Remote control and operation observation
Versions equipped with the corresponding control system can perform remote operation. Operators can control robot movement and cleaning based on the video feed. Specific control functions are subject to the actual equipment configuration.

5. Confirm whether the robot can pass through the target duct section before purchase
Even if the duct dimensions are within the published range, actual clear space, cross-sectional shape, bends, transitions, obstacles, and access opening conditions must also be considered. For narrow or specially configured ducts, equipment passage capability should be verified first.

4. What Are the Product Features of the KT-986 Combined Duct Cleaning Machine?

1. One machine integrates two cleaning methods
The KT-986 combines robotic cleaning and flexible shaft cleaning. The robot is used for main ducts that meet passage conditions, while the flexible shaft uses a brush head to treat duct sections suitable for flexible shaft operation.
When a project involves multiple duct diameters, this design helps select the corresponding cleaning method based on the actual duct section.

2. Overall published applicable duct diameter: 100–800 mm
The KT-986 robot mode has a published range of 250–800 mm, and the flexible shaft mode has a published range of 100–800 mm. Therefore, for ducts of 100–250 mm, the flexible shaft mode should generally be the focus of evaluation. It cannot be directly assumed that the robot itself can also enter this size range.

3. Flexible shaft cleaning suitable for various duct configurations
The flexible shaft can drive a matching brush head to clean inner duct walls and is suitable for verified horizontal ducts, vertical ducts, round ducts, rectangular ducts, and some small ducts.
However, actual applicability depends on duct bend severity, effective space, brush head specifications, and flexible shaft path. The more complex the duct, the more necessary it is to confirm in advance whether the target position can be reached.

4. Video monitoring and vacuuming operation
KT-986 published documentation includes video monitoring, video/photo recording, and integrated brushing and vacuuming. The functional configuration and operating method under specific modes should be based on the manual of the purchased version.

5. A 15 m flexible shaft does not mean 15 m can be cleaned under all conditions
The nominal shaft length reflects the shaft configuration and does not mean all bent ducts can achieve the same effective working distance. The number of bends, shaft layout, brush head size, and on-site operating conditions may all affect working distance.

5. When Should the KT-976 Be Prioritized?

If your project has the following characteristics, the KT-976 should be considered first:

The cleaning target is mainly medium-to-large main ducts.

Target duct section dimensions are within the 250–800 mm range.

Duct clear space and access opening conditions allow robot entry.

Video observation is required during in-duct cleaning.

The project has clear requirements for robot movement, brushing, and vacuuming coordination.

For example, some main ducts in office buildings, commercial complexes, hotels, and similar projects can be evaluated for KT-976 if robot entry conditions are met.
If the project also includes a large number of small-diameter branch ducts, the workload that the KT-976 cannot cover should be further calculated to determine whether other equipment is needed.

6. When Should the KT-986 Be Prioritized?

If your project has the following requirements, the KT-986 should be considered:

Main ducts and branch ducts require cleaning at the same time.

Duct sizes vary widely, including sections of 100–250 mm.

Different duct sections require different tool entry methods.

Robot and flexible shaft cleaning functions are desired within one equipment system.

Project types are diverse, requiring coverage of both medium-to-large ducts and some small ducts.

For example, central air conditioning air systems in comprehensive buildings often have both larger main ducts and branch ducts connected to terminal air outlets. The KT-986 combined design can provide more equipment usage methods for such projects.
However, if special duct sections have severe bends, insufficient space, internal obstacles, or special contaminants, separate evaluation is still required. Judgments cannot be made solely based on the product's applicable duct diameter range.

7. Which Is More Cost-Effective, the KT-976 or KT-986?

Whether equipment is cost-effective cannot be determined by comparing purchase price alone. Actual workload and project structure should also be considered.

If the vast majority of work is concentrated in 250–800 mm main ducts, the KT-976 may already cover the main requirements. If a combined machine is purchased at the same time and one of its operating modes remains idle for a long time, it may not deliver the value of its configuration.

If the project includes both main ducts and a large number of small-diameter branch ducts, the KT-986 combined approach may reduce the need to purchase another separate equipment set. However, whether costs are saved still depends on equipment price, accessories, construction efficiency, personnel arrangement, and usage frequency.

It is recommended to analyze the proportion of each duct diameter based on past projects, then compare equipment solutions, rather than making a decision solely based on model or number of functions.

8. What Information Should Be Provided Before Purchasing the KT-976 or KT-986?

To make equipment selection more accurate, prepare the following information:

Duct diameter or cross-sectional dimensions: For round ducts, provide inner diameter; for rectangular or flat ducts, provide inner width and inner height.

Duct type: Specify main duct, branch duct, horizontal duct, vertical duct, round duct, rectangular duct, or flat duct.

Duct routing: Whether there are continuous bends, transitions, narrow passages, or obstacles.

Contaminant conditions: Whether it is ordinary dust, fibrous debris, or oily or other special deposits.

Construction conditions: Access opening dimensions, equipment placement space, power supply, and vacuum hose layout.

Functional requirements: Whether video monitoring, recording, photo capture, and project documentation are required.

Equipment version: Confirm the specific model, configuration list, and corresponding technical parameters.

Providing this information helps determine whether robot mode, flexible shaft mode, or a combined configuration is more suitable for the actual project.

9. Frequently Asked Questions About KT-976 vs KT-986 Selection

1. What is the biggest difference between the KT-976 and KT-986?
The KT-976 is centered on robotic cleaning, with a published applicable duct diameter of 250–800 mm. The KT-986 integrates robot and flexible shaft methods, with an overall published applicable duct diameter of 100–800 mm. The main difference lies in equipment structure and cleaning method.

2. Which model should be selected for 100–250 mm ducts?
According to published parameters, the KT-986 flexible shaft mode should be evaluated first. Applicability still needs to be confirmed based on duct cross-section, bends, clear space, and brush head configuration.

3. Can the KT-986 completely replace the KT-976?
The KT-986 has a robot cleaning mode, but functional integration alone does not mean the two are identical in all configurations and working conditions. The robot parameters, configuration, and project requirements of the specific version should be compared.

4. Do both machines have vacuuming capability?
Published documentation indicates that both products have integrated brushing and vacuuming designs. Actual vacuuming performance depends on duct conditions, contaminants, and equipment status.

5. Can the KT-976 clean flat ducts?
Published application documentation includes flat ducts, but the actual clear width, clear height, and robot passage conditions of the flat duct still need to be confirmed. Particularly narrow duct sections require separate verification.

6. Can the KT-986 flexible shaft clean all bent ducts?
This cannot be understood in that way. The number and angle of bends, duct clear space, flexible shaft path, and brush head specifications all affect operating capability and should be evaluated based on the specific duct.

7. Can selection assistance be provided based on site conditions before purchase?
First organize duct dimensions, configuration, contaminants, and construction requirements, then communicate with the technical team to verify the configuration and applicable conditions of the corresponding model, reducing the risk of equipment-project mismatch.

10. Company Introduction and Technical Consultation

Anhui Kuaitong Pipeline Cleaning Technology Co., Ltd., established in 2009, is a technology-oriented enterprise specializing in the R&D, manufacturing, and sales of pipeline cleaning, unclogging, and inspection equipment. The company is a National High-Tech Enterprise, a Technology-Based SME, a Training Base of the China Industrial Cleaning Association, and an Anhui Province Specialized and Sophisticated Enterprise. It has provided solutions to more than 23,000 domestic and international enterprises.

For central air conditioning air system cleaning requirements, the company provides duct cleaning equipment with different operating methods. For KT-976 and KT-986 selection, the equipment application scope and configuration can be further verified based on the ratio of main ducts to branch ducts, duct dimensions, site configuration, and construction requirements.

Website: www.kuaitonggroup.com
Technical Consultation (Phone/WhatsApp/WeChat): +86 18226181287

This document is compiled by the technical team of Anhui Kuaitong Pipeline Cleaning Technology Co., Ltd.