Heated Pure Water Generation Build

With all the change in work routine due to COVID, some areas for refinement in our setup came to my attention that we could work on. Long story short, we started in 2019 and quickly built up a WFP setup for our business. Originally, the WFP setup was built to handle a large commercial setup, which necessitated a trailer. The setup has since grown to better handle our needs (probably not the last time). This is a family business and no business shop space is available for us.

Since September/October, we realized how silly it is to leave filters in a trailer, albeit enclosed, when the temps drop below freezing. This didn’t seem much of an issue at first, just simply move the filters into the garage when not generating pure water. As the weather started changing into snow, the idea of making hot pure water to use began to into the brain.

Below are some build shots with a heated pure water generation station that provides the following solutions for our needs:

  • Keep RO and DI filters in an insulated space
  • Provide a means to heat the pure water (providing a longer WFP season)
  • Monitor power consumption for record keeping

This system, in its current state as shown, provides the following:

  • 50A, 2 phase feed from utility with power monitoring for each phase
  • Tankless water heater
  • 12V stepdown for RO booster pump
  • 120v exterior receptacle to power trailer (as needed at home)
  • Frost hydrants for waste and pure water delivery (can generate and deliver water in subfreezing weather while keeping garage insulated)

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Presently, the system generated on average 100* pure water at over a 1 GPM rate. I am awaiting parts for the gauges and inline TDS metering, so the plumbing isn’t final. But the proof of concept works!

To Add:

  • Pressure gauges for filter life monitoring
  • Inline TDS metering for filter life and performance monitoring
  • Bypass plumbing for heater for summer months

What are your thoughts?

so your station is fixed in place, you fill a tank with heated water to transport to job?

Yes, fill the tank for the day’s work. Locally, many of our clients have bad well water or even haul their drinking water to the estate, so we rarely generate water on site.

i purify at home into 250 gal tank in van.
spring and fall i heat water to work below freezing.
i use propane tankless heater to heat water as it enters tank and to heat water in tank.

what is your plan to keep unused water in tank from freezing over night, vehicle inside heated garage?

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We generate water for the day’s work, an estimated amount based on windows and condition. On average, there is about a gallon or two remaining. We “pump” it into jugs for interior work to keep the tank(s) empty. At least that is the plan now as this is the first winter with WFP.

i do not have access to garage.
i use an electric space heater inside van and i heat the water in the tank to 100-130f by circulating it thru the propane heater which then provides thermal mass.
this keeps the pumps, hoses etc from freezing overnight.
one of the most frustrating parts of working sub freezing is having the pole freeze and of course if you don’t manage your hose deployment and flow correctly having 150-200 feet of frozen hose which can happen in minutes depending on the temp.

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Doesnt the water freeze on the glass?

Also, is there any concern that putting hot water on freezing cold glass could crack it?

Yes. You’ve gotta be careful not to run it too hot, especially on well insulated glass. $1800 mistake back in October :confused: (long story, but I’m suspicious that there must have been something defective about the window in the first place)

The water typically evaporates and/or drains off before it can freeze to the glass. The glass is also typically above freezing in all but the coldest weather, due to heat escaping from inside. Anything that does happen to freeze, will dry spot free when it eventually thaws.

You do have to watch out to not ice up walkways, though.

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As mentioned above, there are some dangers. Just because I’m generating 100° water does not mean it will hit the glass at 100°. This is to help me have warm water so that my hoses are warm and easy to work with, and everything flows a little better.

We will be putting a minimum temperature as to when we will be working on glass with this. I don’t want to much of a Delta with the glass in the water. Here in Colorado where there’s a lot of sun, most areas do fine with water fed pole. Most of the siding, drainage, and other areas do not freeze as long as the sun is out, which most of the time.

Ouch! Sorry to hear of your experience regardless of the true cause. That must have been a headache.

Walkways, yeah that’s the rub. We have some clients where we cannot WFP under certain conditions as the walkways are heavily traffic (think commercial) and we don’t want liability. Thankfully, those are not heavily encountered.

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in 4 years i have had 3 crack. 2 of which the water was just a bit warm and the outside temp was not very cold. the crack always comes from the edge starting at a tiny unseeable flaw is. i have washed lots in cold enough that we have to spend time warming the glass enough to melt off the ice, none of those have ever cracked.

Yep, one that is ongoing. Marvin is so far behind schedule, and the custom triangular IGU had to be made to order. The glass shop doing the actual replacement is also swamped; it took them nearly a month just to get there to take measurements, and they’re booked out a couple of weeks on repairs. So hopefully this window will get fixed before February. Headache, indeed.

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@DelirousDungo you should consider heating it as it comes out of the tank so you’re only heating water that is actually being used (250 gal is a lot of water to heat!) I just dump the unused water or keep it above freezing with a space heater. I have quick disconnect on everything to drain the water from the delivery system and take my pump inside.


@Wagonhound as stated i use a space heater, this is not enough in our temps.
the idea of removing 2 heaters 2 poles 2 sections of 200’ of hose, 2 pumps with their hoses, trad cleaning soaps and solutions, disconnecting and removing 2 propane water heaters is impractical as is
starting early enough in the morning to generate 250 gallons of pure water AND replace all the equipment again.
as stated the hot water in the tank provides thermal mass which keeps the van warmer together with the space heater.
my system allows me to leave my equipment set up and in the van throughout the working season. end of day involves refilling the tank for 2-4 hours and heating the water as it as it fills when we are in the colder season.

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@DelirousDungo, makes sense. I don’t clean many windows in the winter so I just fill what I need and all my hoses are easy to drain.

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