UV filter recommendations ?

Dave Carpentier

Would like to install a whole-house UV filter.
Appreciate any tips on features to look for or avoid.
The equipment chain will be 10micron carbon filter, softener, UV.

Jamie Hall

May I ask why? A UV unit is not a filter -- it does one thing, and one thing only: deactivate bacteria (and other living things -- but you're not likely to have algae!)) and, to a lesser extent, virus. How well they work depends in the first place on contact time -- so they are usually rated by maximum flow rate -- and the turbidity of the water (which in your case is likely to be very low).

pecmsg

Carbon Filter? 

What are you trying to filter out?

Dave Carpentier

The NCP-10's act as my whole house filter (including for the softener). These filters have been pretty good balance ( I think) for filtration, flowrate and cost. We get about 5 weeks usage.

The UV is for a new issue of coliform (but not e-coli /fecal). Shocked the well twice, but I dont know the actual ppm of free chlorine, I just used a guide based on the gallons in the well. Its low coliform numbers, but they're there and its supposed to be "0".
We're not drinking it until I get a UV unit installed.

pecmsg

So we’re talking Water Systems. 

Jamie Hall

It sure is supposed to be zero. You may not get sick from it, but guests might very well do (I have a funny story about that and an old man in Vermont -- for another time).

There's good news and bad news here. The good news is that it's not at all hard to get rid of the little buggers in your water -- but I'd go with a well water chlorination system (Google exactly that) rather than a UV filter. I have specified and installed UV disinfection systems for both water supply and waste water, and they do work and work well -- if they are big enough. However, they take maintenance and observation, as without maintenance (mainly cleaning the tubes) they lose effectiveness with time. You might want to take a look at this article: https://www.suezwaterhandbook.com/processes-and-technologies/oxidation-disinfection/ultraviolet-disinfection/sizing-principles for some principles of UV disinfection. Chlorine, on the other hand, while it also requires a detention time, is more reliably controlled in a home type setting. The excess chloring can be removed with the charcoal filter.

Now a word on the charcoal filter. Whatever disinfection system you use, it must be located AFTER the disinfection, not before. Charcoal is a near ideal growth medium for quite an array of nasty critters, and if they are in your water when it hits the filter they will take up residence there very cheerfully. And grow...

Now. The bad news. If your well didn't respond to a heavy shock treatment, there are two possibilities, neither good.

First, and most likely, is surface or near surface contaminated ground water getting into the well. If it is a shallow screened well (rather common) look for any possible sources of contamination in the vicinity -- say within 150 feet -- of the well. One not uncommon source is the building drain to the septic tank being damaged. The septic system itself, if it is within that radius (many are) should also be checked to make sure it hasn't failed, and that the tank has been pumped and checked recently. Also, on a small lot, look at your neighbours... if you find something, it must be eliminated or repaired before the well can be regarded as safe.

Second, if the well is a deep well with a casing, there are again two possibilities. By far the most common is that the casing is damaged, or the pitless adaptor, and is allowing near surface water into the well. This sometimes -- but not always -- shows up as turnidity in the water. The second possibility is rare, although I've seen it, and is that the rock aquifer itself is contaminated. As I say, this is very rare -- I've only seen one or two examples in some 50 years in this racket -- but by the same token can be very difficult to correct, if not impossible. For this one you would need to get your public health authorities involved, as they will want to check other similar wells in the area as well as trying to determine the source (one example I recall was traced to a septic system fully a quarter of a mile away...)

Good luck. You may PM me for further comments or thoughts, if you like.

Dave Carpentier

I dont believe its septic, as that should flag e-coli /fecal that the lab also tests for, and that always comes back 0.
The current plan is to UV it (although I'll look into that continuous chlorination) and keep testing the source to see if it ends up being transient. If it continues, it might be roots from nearby evergreens trying to work their way into the first tile junction (about 2ft down). Would need a backhoe to dig up , lift tile section and put new mastic (and then execute the trees).

Brent H.

When you shocked your well, did you sanitize your water softener and other filter equipment? I went down a similar path and the problem turned out to be my softener instead of my well. Sanitized the softener then tests came back clean.

Jamie Hall

Dave Carpentier said:

I dont believe its septic, as that should flag e-coli /fecal that the lab also tests for, and that always comes back 0.
The current plan is to UV it (although I'll look into that continuous chlorination) and keep testing the source to see if it ends up being transient. If it continues, it might be roots from nearby evergreens trying to work their way into the first tile junction (about 2ft down). Would need a backhoe to dig up , lift tile section and put new mastic (and then execute the trees).

You may have found the problem. Surface water does not always show coliform, oddly, but other bugs can also make you sicker (coliform is an indicator). Get it fixed... and put the UV or chlorine FIRST in the water supply chain.

EdTheHeaterMan

Perhaps he is taking a picture of the heating system...
I have used this type of filter since high school camera club.

Dave Carpentier

True Ed. A UV filter is a pretty cheap lens protector too.

@Brent H. - Interesting. Although I did do the original test (when this started) with "raw" water before the carbon filter and softener, this last time I took it from a faucet because I was in a rush. If its in the softener, it wouldnt have been shocked (bypassed to protect the media). I will retest "raw".

ChrisJ

pecmsg said:

So we’re talking Water Systems. 

The softener gave it away to me, but at first I thought air.

GGross

I have been quite fond of the sanitizer plus from Water Right since we started selling them. It has a chlorinator built in. It uses different media so the media bed will not be destroyed by the chlorine, just mind that you use a solar purified salt and not the regular stuff. We have tons of iron bacteria around here and these get rid of that stuff quite thoroughly.

https://www.water-right.com/sanitizer-plus/sanitizer-plus/