So it’s just a case of adding the pure and waste together. I also have a booster pump which increases the pressure to 70-80psi. Does this increase the mains flow by drawing more water through the pipes? Or is it the same flow, but it somehow concentrates the flow into high pressure
Some people report that increasing the water pressure reduces the amount of waste. I can't comment as I have never had a Merlin or a booster pump.
What I do know is that a fellow windie down the road has one and his waste to pure was around 5 to 1 on our 50psi without a booster.
Gold has the PRF which is the latest model. He reports that his waste to pure is about 3 to 1. I'm not sure if that's because he has a high water pressure or if the PRF has been 'reworked' to be more economical with regard to water usage. The PRF is in competition with the 4021 which is a much more efficient r/o IMHO.
Theoretically, a booster pump shouldn't make much difference to your water consumption. The higher pressure means the filtration cycle should be shorter.
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