UV System

[Cindy V]

Aloha all.

I have heard that a UV filtering system associated with catchment will considerably diminish water pressure? True False alternatives?

Thanks

[Ironman]

Cindy:

The UV system just diverts the flow through a tube that exposes the water to ultraviolet light that is designed to kill the bacteria. The single point of failure with UV is the bulb must replaced frequently based on use. It may still light but if the intensity has dropped it will not kill the bacteria. Good systems have a meter that alerts you to the diminishing light intensity so you can change the bulb.

What usually reduces the water pressure is a sediment filter (1-5 microns) that is directly in the line.

I have a sediment filter on my system first, then the ultraviolet system, which then feeds into the Reverse Osmosis (RO) four stage filter. I would not drink any water unless it has gone through a RO filter first.

You will need a higher PSI water pump but it is worth it in the long run. If you go with a good RO unit you can eliminate the UV.

Best regards,

Will Peratino

[Andrew]

We have a UV and sediment filter on our catchment system. The recommended time frame for replacing the bulb is 1 year. The UV itself does not diminish the pressure.

Andrew

[Cindy V]

Is it the sedament filter that reduces pressure or is the pressure not reduced at all?

Mahalo

[Ironman]

Cindy:

The UV system does not diminish the water pressure.

The sediment filter will diminish the PSI or flow rate of the water but that can be mitigated by using a higher PSI rated water pump.

The Reverse Osmosis system is usually comprized of three stages (1) Sediment Filter, (2) Charcoal Filter, and (3) a permable membrane that the water is forced through. Most R/O systems recommend a minimum of 50 lbs PSI water pressure to get the number of gallons stated in the system documentation. The R/O will definetly reduce the flow rate and will not produce the listed gallonage on a daily basis unless the water pressure is at least at the minimum per the systems specifications.

Bottom line, if you want drinkable water from your catchment system or even from city/county water sources I would use the R/O approach.

Hope this helps,

Will Peratino

[emorata]

cindy,

you can have the RO sytem set up underneath the kitchen sink separately to feed up through the sink and feed to fridge, regular water use to wash dishes, laundry do the shower, you can hook up directly to from the pump/UV/sediment filter so you get better flow to the fixtures you want to use that needs more pressure. (thats how we do it here in norcal, i'm sure its the same in puna)

on another note, if you want to have exterior faucets to water the plants or do an outdoor shower, would you want to filter any of the water from the catchment and then pipe it back out or does it make sense to have water go directly from the catchment?

noel

[Cindy V]

To UV or to RO that is the question. Is it nobler to UV the whole house, will my pressure fail or to UV the kitchen?

This poor poet needs help!

[David M]

Cindy

Good question Practically from the moment I realized we'd be on catchment, I thought I'd do a total UV system. Now that I've a tad practical experience, I'm not so sure. I guess part of what got me thinking is in another related thread I did some research that also involved municipal treatment. Neither UV nor RO appeared as part of standard practices. One woud have to admit, that most municipalities start with some pretty disgusting water if you trace is back to all the sources. What I've decided is to be more mindful of getting cleaner water into a closed system, then treating. I have to say my current system has as better tasting/appearing water as any I paid for in GA. There we did carbon block to improve taste etc. Once I get the main house system together, I will get it tested before I make the UV decision. I could be wrong, but in limited observation those doing UV/RO tend to be the newer residents. Exception - the one RO setup I'm familiar with is a local but they RO county water. It does taste better!!!

Just another 2 cents.
David

Ninole Resident

[jdirgo]

I'm happy with my UV system. Being on catchment and a cesspool, this quote turned me away from a RO system.

"RO units use a lot of water. They recover only 5 to 15 percent of the water entering the system. The remainder is discharged as waste water. Because waste water carries with it the rejected contaminants, methods to re-cover this water are not practical for household systems. Waste water is typically connected to the house drains and will add to the load on the household septic system. An RO unit delivering 5 gallons of treated water per day may discharge 40 to 90 gallons of waste water per day to the septic system."

http://www.ext.nodak.edu/extpubs/h2oqual...e1047w.htm

John Dirgo, RA, ABR, e-PRO
Island Trust Properties, LLC
808-987-9243 cell

[Ironman]

Folks:

I suggested the R/O approach at the beginning of this thread. It is designed for Point-of-Use (POU) applications on ONLY the water you drink or in the ice maker in your refridgerator which are actually small amounts on a daily basis compared to overall usage. All other water that you use can be exposed to UV, sediment, and or carbon filtration and it will be fine. As far as losing large volumes of water that are used to flush/clean the R/O systems membrane I offer the following: I have recycled "Grey water" for years for irrigation purposes etc so if you look at your system, determine your water uses properly. You can design a way to re-use the water that the R/O system uses to backflush or clean the membrane. Remember, the UV approach ONLY KILLS BACTERIA it removes nothing else from the water that are know contaminants.









Best regards,

Will Peratino