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10 Common Mistakes in Pure Water Window Cleaning

For window cleaning professionals evaluating the value of pure water window cleaning, it’s common to wonder if the results from pure water cleaning are better than classic window cleaning. Our take – both methods are effective when employed by a skilled window cleaner who knows what mistakes to avoid.

Whether you choose to execute the job with a traditional washer and window squeegee or with a pure water window cleaning system, either method if done incorrectly could leave behind residue or streaks. For pure water window cleaning, it is especially important to know which mistakes to avoid, as you want to make sure you’re getting the results you and your customers expect from your pure water system investment.

Checklist of Pure Water Window Cleaning Mistakes:


1. Not Prepping Windows Before Washing

If your windows are not heavily soiled with dirt, dust, or other contaminants, then you are good to proceed with washing. However, if they appear to be heavily soiled, pre-rinsing or manually removing stubborn areas of grime before proceeding to the wash phase will ensure a more thorough clean and prevent streaking.

2. Understanding the Impact of Chemical Residue

Using pure water technology on windows previously cleaned with a more traditional window cleaning method – washer, squeegee, cleaning solution – could jeopardize your ability to achieve a streak-free result.

When cleaning with classic methods, if the windows are not rinsed thoroughly, or if too much cleaning solution is used, you run the risk of leaving behind excessive chemical residue. This residue can manifest as streaks, smudges, or a cloudy appearance on the glass once the cleaning solution dries. When starting with pure water cleaning, you may see this issue impact your results at first, but it is a temporary problem and resolves itself naturally after your first few pure water cleaning cycles.

3. Cleaning with Water above 10 TDS

When pure water used for cleaning glass exceeds a value of 10 ppm (parts per million) of total dissolved solids (TDS), it may not be as effective in producing streak-free and spot-free results. Higher TDS levels mean more impurities in the water than there should be for an optimal pure water cleaning experience.

These higher levels create an increased risk of streaking, the formation of water spots, and reduced cleaning efficiency. Higher TDS levels can also impact the performance and lifespan of the pure water cleaning system’s components with minerals and impurities eventually building up and causing clogs.

To maintain optimal cleaning results with pure water technology, it’s important to regularly monitor the TDS levels of the water used and ensure that it remains below the recommended threshold, typically around 5-10 ppm.

4. Avoiding Defective Window Seals and Joints

Water can infiltrate into the window frame and between the glass panes when cleaning around defective seals and joints. Once the water infiltrates the window, any impurities and contaminants from the window frame can be picked up and distributed to the glass surface. As the water travels down the surface and dries, it can result in streaks or spots and reduce the effectiveness of pure water window cleaning.

5. Cleaning in the Wrong Direction

We always recommend starting from the top and working your way down to the bottom. This way, dirt, grime, and contaminants washed off the upper parts of the window can drip down onto areas not yet cleaned.

6. Cleaning Glass Before Frames

Outdoor window frames harbor dirt, grime and debris with levels varying based on the geographic location, local weather conditions, surrounding environmental factors, quality of building maintenance and the material composition of the window frames. If you clean the glass first, any runoff from cleaning the frames can potentially contaminate the clean glass, necessitating additional, time-consuming cleaning steps. That said, frames should always come first in the order of cleaning.

7. Using Dirty Equipment

Any equipment used in the cleaning process, including waterfed poles and brushes, must be cleaned prior to cleaning the windows. If these components have any dirt and contaminants on them, when cleaning, these impurities can be transferred onto the windows and you may risk damaging your glass.

8. Cleaning All Window Materials the Same Way

Pure water window cleaning systems are generally effective for cleaning a wide array of window materials, including glass, vinyl, aluminum, fiberglass and wood. While pure water technology is most effective on glass surfaces, it works well on other materials as long as you take into account the characteristics of each material, such as porosity and surface texture, and adjust cleaning techniques accordingly to achieve optimal results .

9. Treating Bonded vs. Non Bonded Windows the Same

For windows that have been bonded (coated), you need to consider which window cleaning tools and what water pressure is best to accommodate for the bonded seals. High-pressure water streams or aggressive scrubbing with a brush may compromise the integrity of the seals, leading to leaks or damage. Given the variety of window brushes available, if you’re in doubt about which one to use, start by checking its performance on a test surface.

10. Not Asking for Help

Lastly, good advice is not expensive. Whether you are just getting started with pure water cleaning or you are a professional looking to increase your knowledge, there are multiple communities available to help. A great place to start your research is with the International Window Cleaning Association. You can also contact us with any problems or questions you have around pure water window cleaning and we would be happy to help.

Our team of Unger Commercial Window Cleaning Equipment Specialists is on hand to guide you through any challenges, offer personalized advice, and ensure you’re equipped with the knowledge and tools you need for spotless results every time. Whether you’re new to the game or looking to refine your skills, we’re here to support you in achieving window cleaning excellence.

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