A water-fed pole system uses purified water in conjunction with a pole and brush or other attached tool to clean windows, building surfaces, vinyl awnings, truck trailers, cars, etc.
Pure Water Creation and Use
Pure water is created by removing the sediments and total dissolved solids (TDS) from the water. The process involves a chemical and electrical process called De-Ionization (DI), it’s the key to pure water cleaning, electrically removing the dissolved solids turns the water into a safe, yet effective cleaning agent.
Small-scale systems use a combination of filters, membranes and DI resins to accomplish the task of creating pure (near zero TDS) water. Large-scale systems use electricity to separate the dissolved solids from the water. Most building cleaning uses small-scale water purification to create pure water.
Glass cleaning is the most demanding use of pure water for cleaning. “Pure” is defined by the parts per million of dissolved solids, typically things like iron, calcium carbonates and silica that remain in the water. This industry measures pure water as X TDS.
TDS must be below these levels for these surfaces to avoid visible spotting:
a. Glass – less than 10
b. Car paint – less than 50
c. Textiles, carpet, upholstery – less than 50
d. Building surfaces – less than 60
Why Pure Water Works:
Tap water (city water) has a number different kinds of dissolved solids held in suspension in the water. When the water is purified these solids are removed, however pure water wants to return to its naturally dirty state.
It attracts dirt from the surface like a magnet; pure water wants to become dirty water and drag that dirt to the ground. Once the dirt is gone, the pure is all that’s left of the glass, and will dry clean and spot free.
Real World Implications?
Pure water cleaning is great in principal, but there are several obstacles to overcome for great results. The general issues are as follows:
1. Getting the water to the glass is generally accomplished with a water-fed purification system designed to either a) carry pure water, like a tank, or b) make pure water on demand. The water is pumped up an extendable pole and out the brush via a nozzle.
2. Agitating (loosening) the dirt from the surface.
a. Water by itself is not enough the dirt and grime needs to be scrubbed off with a brush.
b. Improper agitation will show up as vertical stripping of the dirt; or hazing in the corners; some but not all of the dirt was scrubbed away.
3. Rinsing the glass after cleaning – when water is applied to glass it will either sheet off leaving a clear surface, or bead up and leave pure-water droplets.
a. Glass where water sheets off is called Hydrophilic and is easier to rinse. Start at the top and rinse side to side far enough down to allow the pure water to sheet all the way down to the bottom of the glass.
b. When the water beads up the glass is known as Hydrophobic and is more difficult to rinse. Start at the top and insure that every area of the glass is hosed down by the pure water flow, go slowly and watch for water that is flowing around certain areas of the glass surface. If you see spotting here it is usually due to an incomplete rinse; a droplet that still contained some dirt dries and spots the glass.
Small System Creation of Pure Water
Small systems use DI resin to capture the TDS in the water, rendering the water pure and actively wanting to be dirty again. The DI resin is made up of positively and negatively charged resin particles that attract and capture the many different kinds of dissolved solids suspended in the water.
Once each receptor has absorbed the solids, the resin will stop cleaning the water. Just like some batteries, DI resin can be recharged or replaced.
Depending upon your location, TDS can range from near zero to over 1200ppm (parts per million). Many places in the US have fairly high TDS. The
map below describes the average TDS regionally in the United States.
A handheld TDS meter is an inexpensive tool to understand the water in your market as the TDS readings can vary substantially across town. The higher number the more difficult and expensive it is be to get the water.
Where the TDS is above 90
DI resin by itself will quickly be consumed and the cost of pure water per gallon will grow to be expensive. When the local water is above 100ppm TDS, it becomes important to pre-filter the water before the deionization. There are many different systems available, but they all have the same core components and filters in the same order:
1. Sediment filter to remove solids (often combined with the Carbon Filter)
2. Carbon filter to remove chlorine from the water (chlorine damages RO membranes)
3. Reverse Osmosis Membrane to pre-filter 90% of the dissolved solids. RO Membranes require good water pressure to perform well, they need 60psi or more and work even better at 150 to 180 psi. The RO filter separates tap water into two streams 90% cleaner water and bypass dirty water (often to three times the tap water TDS). When using an RO filter there will always be some dirty bypass water runoff.
4. DI Resin that filters the water to meet your TDS goal.
To keep things simple we will break the available equipment into four categories:
1) DI Resin only systems – below 100 TDS
2) Entry Level RO-DI Systems
3) Mid Range RO-DI Systems
4) Commercial Class RO-DI Systems
1) DI resin only systems are meant for areas where the TDS is less than 100 or there are too few cleaning jobs performed per month to justify a larger system.
a. These run off city water pressure.
b. Can clean up to five stories without a pump.
c. No pre-filters to protect the DI.
d. Cost beytween $125 and $600
2) Entry Level RO-DI Systems:
a. Super portable, hand carried or a simple cart.
b. Operate without a pump (will need input water pressure of 60psi).
c. Clean one to three stories
d. Can add a pump when water pressure is low (will allow multiple poles).
e. Cartridge based Carbon and DI Resin replacement filters.
f. Cost between $1,600 and $2,400.
3) Mid Range Systems:
a. Operate with a 12v. or 120V. electric pump
b. Can provide water to multiple poles.
c. Clean up to 10 stories.
d. Constructed on a sturdy cart frame.
e. Cartridge based Carbon and DI Resin replacement filters.
f. Cost between $2,900 and $5,000.
4) Commercial Class RO-DI Systems:
a. Operate with a gas engine, 12v or 120V electric pump
b. Offer greater water flow for multiple poles
c. Are constructed on a sturdy cart frame
d. Cartridge based Carbon and DI Resin replacement filters.
e. Cost between $4,000 and $6000.
Each manufacturer configures their systems with filters of various sizes. This will impact the service interval required for changing the filters.
The Cost of Water
Using DI Resin alone can get expensive.
• 100ppm will cost about 12¢/gal. to clean
• 200ppm hard water, about 24¢/gallon
• 400ppm very hard water, about 48¢ per gallon.
The typical rate is just less than a 1-gallon per minute. A typical worker will consume 50 gallons an hour. Let’s assume that the pure water is used 6 hours a day, 20 days a month, 12 months a year.
Pre-filtering with an RO Membrane system will cut these cost by 80 to 90%. Then the DI is just the final cleaning; the savings in DI resin cost can quickly pay for an RO-DI system.
The Higher the TDS in your area, the quicker you save money. As a guide, if you are spending $200 per month in DI and your water is above 100, you should investigate system.
These extendable poles with brushes at the end are available in many different sizes and brush styles that are designed to clean specific surfaces. Seasoned operators will have several poles of various lengths and brush bristle types. For instance, small poles from 4 ft. to 18 ft. long are designed first floor work. While a 30ft pole will do the 2nd and 3rd floor of most residences. Though you do need to watch for slopes, and walk out basements that can add to the distances to reach the area to be cleaned.
Generally, the pure water is pushed to the end of the pole and out the between bristles. The brush is pushed up and down which agitates and removes the dirt. Pure water will collect and drag the dirt off the surface down the building. Then the rinse water will dry spotless. There is a learning curve to get this right, rinsing can be done through the brush or the brush can be angled or held away from the glass to allow the stream to rinse with less brush movement.
Most window cleaners own a variety for different surfaces, and
based on preference (trial and error).
1) The most popular is a straight cut nylon bristle brush
2) Boar hair cleans faster & clean very dirty glass the fastest
3) Stiff bristles for brick, concrete and block walls
4) Flagged or flocked bristles for canvas or vinyl awnings and gutter exteriors
Brush Head Jets
Most cleaning is done with pencil jets as this minimizes overspray or bounce back onto other glass. When the glass is highly hydrophobic glass Fan Jets can be used to aid in
There are windows out there that have more than dirt on them and will require some detergent to clean the glass first, this can be as easy as pre-scrubbing with an extension pole and a washer sleeve with detergent solution mounted on the end. In cases where you are cleaning above the length of an extension pole the detergent can be run up the pole by using a chemical pump and a second hose line.
Advances at the Top of the Pole
Water-fed poles have created a world of opportunity for window cleaners. Innovative manufacturers are striving for even better productivity and results. These innovations can help you clean challenging surfaces and open doors to more cleaning opportunities.
Add ACME thread devices to you Euro pole. Use the RHG Reach Around
Use you favorite ACME or Cone tip tools to tackle tough to clean glass.
Add additional Euro tip devices to the top of you pole with the Unger Y Adaptor.
Aluminum. Features two Euro-threads. Both posts rotate and lock in place.
These adapters provide a mount for a scrub pad or scaper on the back side of the brush. They also hold microfiber pads for interior cleaning.
|Radius Sill Brush|
Bristles on the bottom make it possible to clean and sweep sills.
For cleaning small areas. Put on pole, or hand hold.
Quick release for Euro angle adapter.
Apply soap solution above your brush. Connects to Euro adjustment knob.
Turn water on and off with a gentle tug of the hose at the bottom of your pole.
|Carbon Fiber Goosenecks|
Reduced weight makes pole management much easier.