Qiwei PH-220W for Cooling Tower and Boiler Water Testing Malaysia
Regular pH measurement is an important part of cooling tower and boiler-water treatment. Incorrect pH conditions may contribute to corrosion, scale formation, reduced heat-transfer efficiency and higher maintenance costs.
The Qiwei PH-220W External Electrode Portable pH Meter provides a convenient solution for routine checking of cooling tower water, boiler-water samples and other industrial water-treatment systems.
Its external wired electrode allows the probe to be placed inside a sample container while the operator holds the display separately.
The Qiwei PH-220W is available from stock at MTM Precision Malaysia.
Why Is pH Important in Industrial Water Treatment?
Water pH affects chemical reactions, corrosion behaviour, scale formation and the performance of water-treatment chemicals.
When pH is not properly controlled, a cooling or boiler system may experience:
Increased metal corrosion
Scale formation
Reduced heat-transfer efficiency
Higher chemical consumption
Unstable treatment results
Premature equipment deterioration
Increased cleaning and maintenance
Unexpected system shutdowns
The correct pH range depends on the system materials, operating conditions and water-treatment programme. Operators should follow the limits recommended by their water-treatment specialist, chemical supplier or equipment manufacturer.
Cooling Tower Water Applications
Cooling towers continuously lose water through evaporation. As water evaporates, dissolved minerals and treatment chemicals may become more concentrated.
Routine pH monitoring can help maintenance teams assess:
Makeup water
Circulating water
Blowdown water
Chemical-treatment performance
Changes after dosing
Unexpected water-quality variation
The Qiwei PH-220W can be used for convenient spot checks at different sampling points.
Boiler-Water Applications
Boiler systems may require pH testing of:
Feedwater
Condensate
Treated makeup water
Boiler-water samples
Blowdown samples
Water-treatment tanks
Hot boiler water should not be measured directly with the PH-220W.
The instrument’s specified temperature range is 0 to 50°C. Samples must be collected safely and allowed to cool to a suitable temperature before measurement.
Sampling procedures should follow the facility’s safety rules and water-treatment programme.
Why Choose an External-Electrode pH Meter?
A normal pen-type pH meter requires the complete sensor end of the instrument to be inserted into the sample.
The Qiwei PH-220W uses an external wired electrode, allowing the operator to place only the probe inside the sample container.
This design is useful when:
The sample is collected in a narrow bottle
The measuring point is inside a small tank
The display needs to remain clearly visible
The instrument body should be kept away from splashes
Multiple water samples need to be tested
Greater positioning flexibility is required
The external electrode does not mean that the complete instrument is waterproof. Users should keep the main meter dry and protected during field measurements.
Key Features of the Qiwei PH-220W
0.01 pH resolution
Measures pH and temperature
External wired pH electrode
Three-point pH calibration
Portable and lightweight design
Suitable for factory and plant-room use
Convenient for sample bottles and tanks
Clear digital display
Available from stock in Malaysia
Main Technical Specifications
Model: Qiwei PH-220W
pH Measuring Range: 0.01 to 14.00 pH
pH Resolution: 0.01 pH
Temperature Range: 0 to 50°C
Temperature Resolution: 0.1°C
Calibration: Three-point pH calibration
Electrode Type: External wired pH electrode
Power Supply: Four 1.5V batteries
Dimensions: Approximately Ø40 × 185 mm
Weight: Approximately 88g
Specifications and supplied accessories may vary according to the latest production batch. Please confirm the current configuration with MTM Precision before ordering.
How to Test Cooling Tower Water
Collect the sample from the designated sampling point.
Use a clean sample container.
Check that the sample temperature is within the instrument’s operating range.
Calibrate the meter using fresh pH buffer solutions.
Rinse the electrode with clean or distilled water.
Insert the electrode into the sample.
Move the electrode gently to remove trapped air bubbles.
Wait for the reading to stabilise.
Record the pH value, temperature, location and testing time.
Rinse the electrode after measurement.
For consistent trend monitoring, use the same sampling point and procedure each time.
How to Test a Boiler-Water Sample Safely
Boiler water can be hot, pressurised and chemically treated. Only trained personnel should collect samples.
After the sample has been safely collected:
Allow it to cool to a suitable temperature
Keep the container covered where appropriate
Test the sample without unnecessary delay
Record the sampling point
Record the sample temperature
Follow the facility’s approved water-testing procedure
Do not place the PH-220W electrode directly into a hot or pressurised boiler line.
Why Should Temperature Be Recorded?
pH readings can be affected by sample temperature. A reading taken from a warm sample may differ from a reading taken after the sample has cooled.
Recording the temperature helps operators compare results more consistently.
When monitoring trends, try to test samples under similar conditions and using the same procedure.
Common Causes of Unexpected pH Readings
An unusual pH result may be caused by the water system or by the measurement process.
Possible system-related causes include:
Incorrect chemical dosing
Empty chemical tank
Dosing-pump problem
Changes in makeup-water quality
Excessive concentration in the cooling tower
Contamination
Incorrect blowdown rate
Water-treatment equipment failure
Possible measurement-related causes include:
Dry or dirty electrode
Expired calibration buffer
Incorrect calibration
Sample temperature outside the specified range
Cross-contamination between samples
Insufficient stabilisation time
Damaged or ageing electrode
Always verify an unexpected result before adjusting chemical treatment.
Should pH Be the Only Parameter Tested?
No. pH is only one part of cooling and boiler-water management.
Depending on the application, maintenance teams may also monitor:
Conductivity
Total dissolved solids
Temperature
ORP
Dissolved oxygen
Hardness
Alkalinity
Chloride
Silica
Treatment-chemical concentration
The required parameters depend on the system and water-treatment programme.
Electrode Cleaning and Storage
Cooling and boiler-water samples may contain treatment chemicals, minerals and suspended contamination.
After testing:
Rinse the electrode thoroughly
Avoid aggressive wiping of the glass sensor
Use an appropriate cleaning method if deposits are present
Keep the electrode sensing area hydrated
Store it with suitable pH-electrode storage solution
Recalibrate the meter regularly
Do not store the pH electrode dry or continuously immerse it in distilled water.
Correct maintenance helps improve response time and measurement consistency.
Who Should Use the Qiwei PH-220W?
The Qiwei PH-220W is suitable for:
Factory maintenance teams
Water-treatment contractors
Facility-management companies
HVAC service companies
Boiler-service technicians
Cooling tower operators
Building maintenance departments
Manufacturing plants
Hotels and commercial buildings
Data-centre facility teams
It is intended for routine operational checks. Applications requiring certified laboratory results should use the appropriate laboratory method and documentation.
Qiwei PH-220W Available in Malaysia
The Qiwei PH-220W External Electrode Portable pH Meter is available from stock at MTM Precision Malaysia.
Customers may contact us for the current quotation, stock availability, supplied accessories and electrode information.
Contact MTM Precision
MTM Precision Sdn. Bhd. (744811-A)
Telephone: +603-8080 7172
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com / enquiry@mtmpre.com.my
Website: www.mtmpre.com.my
Showroom & Service Centre
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor,
Malaysia.
18 Sep 2026
