If you’re debating between purchasing a DI only filter WaterFed® system and a multistage filter WaterFed® system, this post might just be the advice you were searching for. For this post, we are going to crunch some numbers, because after all, what is more proof than proof itself?

In another video we created, we made the bold statement that multistage systems are 10 times more cost efficient than a DI only system. To check out that video, click here, but to see some cold hard numbers, stick around. So how did we come up with that number? After all, that is a hefty accusation. What we did was we calculate the cost of each gallon of water and compared the two. If you are having terrible flashbacks to high school math class, know that you’re not alone. But unlike high school, this math is already done and it directly affects your business and its profits. Without further ado.

To do this math, we used the Unger HydroPower DI only WaterFed® system and the Triple Crown Phaser multistage system. The math changes with each system, so we used the most basic example to show our math. The same math can be done with any and all WaterFed® systems and we encourage you to crunch some numbers for your own scenario.

## Unger DI System

First, begin with the number the system is rated for; this number will come in gallon increments. In this case, Unger says the DI only system is rated for 300 gallons at 100 tds. 100 TDS is the standard used in WaterFed® math because for the most part, water from a faucet enters into the system with an average of about 100 total dissolved solids per gallon in it. Unless otherwise specified, all our WaterFed® systems assume that the water you are running through it has an average of 100 total dissolved solids being filtered through it. This is how numbers and ratings can be calculated. So, what does this rating number actually mean? It means that this system will filter 300 gallons of water before it needs to be replaced. The cost of the Unger DI filter replacement is $66.74 (as of October 4th 2016). Here comes the math, hold onto your seats. When you divide the cost of the filter, $66.74, by the number of gallons the system is rated for, 300 gallons, you get the total cost of each gallon, which in this case is $0.22247, rounded off, 22 cents. Remember this number, we’ll come back to it.

The next filter in the system is the RO, or reverse osmosis filter. This filter is rated for 100,000 gallons at 100 TDS. The current replacement cost for this filter is $495.00. When you work the math, that means the cost of one gallon of purified water costs $0.00495.

The last filter in the Phaser system is the DI filter. This filter is rated for 5000 gallons when used with the other two filters. (Why is this filter rating so drastically different than the Unger Di filter? Click Here.) The current replacement of this filter is $36.10. When you divide the cost of the replacement by the systems rating, $0.00722 becomes your cost per gallon.

So, add all those number together to get the systems total cost per gallon. In this case, $0.00495+$0.00722+$0.00752 equals $0.01969, about 2 cents per gallon, which is the total cost per gallon with the Triple Crown Phaser system.

When you compare the two numbers, the total cost of a gallon of purified water, for the DI only system versus the Phaser multistage system, you’re looking at 22 cents per gallon for the DI system and 2 cents for the multistage system, equaling, in this case, an 11.2 times cost difference between running the DI and the Phaser. So all in all, the Di only system is 11.2 times more expensive to run than the Phaser.## Triple Crown Phaser Multistage System

So now, we will switch over to a multistage filter WaterFed® system, in this case, the Triple Crown Phaser system. Like we did with the DI system, we begin this equation with the rating. Because this system has multiple filters, each one has its own rating. At the end, we will add all of them up to get the total cost of a gallon of water from the Phaser. The first filter is the carbon filter. It is rated for 5,000 gallons. (Wondering how this rating is so high? Click Here.) The replacement cost, as of October 4th 2016, is $37.62. When you divide that out, the cost of the replacement by the number of gallons the system will process before it needs to be replaced, the rating, you get $0.00752.The next filter in the system is the RO, or reverse osmosis filter. This filter is rated for 100,000 gallons at 100 TDS. The current replacement cost for this filter is $495.00. When you work the math, that means the cost of one gallon of purified water costs $0.00495.

The last filter in the Phaser system is the DI filter. This filter is rated for 5000 gallons when used with the other two filters. (Why is this filter rating so drastically different than the Unger Di filter? Click Here.) The current replacement of this filter is $36.10. When you divide the cost of the replacement by the systems rating, $0.00722 becomes your cost per gallon.

So, add all those number together to get the systems total cost per gallon. In this case, $0.00495+$0.00722+$0.00752 equals $0.01969, about 2 cents per gallon, which is the total cost per gallon with the Triple Crown Phaser system.

The real question is, we have these numbers, but what does that mean in the real world? This means that once you work beyond the initial investment, a Phaser multistage system ($1,045.00 as of October 4th 2016) is 11.2 times less expensive to run than the DI system ($413.99 as of October 4th 2016), though the initial investment for the Di system is 39% more expensive. If you are looking to use your WaterFed® system regularly as a part of your window cleaning routine, it is a good idea to consider a multistage system because of the lower running cost. The lower cost of operation will end up being less expensive for you in the long run.

## Comments

how does one keep track of how much water is being used? Is there some sort of flowmeter available that can keep track?

Hey Pete,

We do have a meter for the Enterprise system. https://www.window-cleaning-supply.com/products/Waterfed-%C2%AE-%252d-abc-Time-Saver-Wear-Parts-%252d-Replacement-Flow-Meter.html