Why waste hot water...it's going down the drain...unless you use 100% of the elevated tds water for watering plants or whatnot. People talk about how much systems costs when up and running using hot water would just be another energy bleed. I use straight cold in Calgary and happy with the product of my unit.

I threw on a pressure gauge and adjustable valve on the water input keeping it @ 70-75psi and never looked back with any problems.

Right, Ill keep my eye open for the right deal on a booster pump then.

yeah fix the pressure with a booster pump and practice smart ro/di use. flush before and after. bypass resin until ro output is low.

i checked my unit after i was halfway done filling my new tank. it read 0 TDS after the ro membrane and that's in Calgary too.

Im eyeing this unit here as it is local to me and a great price

https://maxwaterflow.3dcartstores.co...mps_c_146.html

By the looks of it there are high and low pressure switch options What should I do about those? Would this just make the pump run "on demand" with these? Im hoping for a relatively autonomous solution.

Thanks!

If you are stuck on that co because it is local and you have a 100gpd RO unit then this is what you need.
https://maxwaterflow.3dcartstores.co...es-_p_554.html
You never said how many gpd unit you have. There are other units on that page u linked to that would match your gpd ro if you do not have a 100gpd.

The units come with instructions and they will turn on and off automatically when the pressure drops/rises. You just need a 110V outlet under the sink, or wherever your ro unit is located

sorry, I have a 75gpd unit. They have a unit that matches that.

As a plumber I recommend you DO NOT use warm or hot water in your RO/DI. Any potable water that passes through a boiler/heater will contain higher levels of the crap you are trying to remove reducing the life of the membranes. Do yourself a favour and get a booster pump!

Most RODI systems that come with a pressure gauge recommend installation before the RO membrane (after the pre-filter & carbon stages). I've taken it a step further & installed two pressure gauges, one as per above recommendation & another at the RODI system input, measuring house pressure. This allows me to keep track of a pressure differential between the two & is one of the best indicators of when your pre-filter stages need replacement. Using simple math, when the pressure differential reading between the two begins to rise 3 to 4 psi, it's pretty obvious the sediment filters are gumming up. I keep track of the numbers on an Excel spreadsheet. Although the poly pre-filters aren't that costly, it's still more cost effective & less of a hassle to change them when truly required rather than on some arbitrary time based schedule.

I purchased both gauges at Princess Auto. Liquid filled, good quality for just under $20. No need to order something through the mail when it's available for competitive price locally.

To compensate for cold water in the winter i got about 20 feet of water line wraped around the inside a 5gallon bucket then filled the bucket with water and put a heater in it. So the water goes from the water source, warms up from the warm bucket water then into my rodi unit. Seems to help a bit.

On what chewy said, I could probably just wrap the water feed line around the hot water pipe under the sink.

All that being said. My carbon and sediment replacements as well as fresh batch of DI resin and my pressure has takes a substantial step up. Im still sitting at 35psi, but thats a whole lot better than the 10 it was before.

Booster pump is on the "things to buy" list