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38 Forest Knoll Dr water

before:

video: Total Coliform in Well Water
video: bleach shock is bad for septic
UV works if water is without iron and not hard
UV pre-treatment
UV treatment water Parameter Limits 
Iron under 0.3 ppm
Manganese under 0.05 ppm
Hardness under 7 grains per gallon
home water test kit
Using a HEAVEIS 17in1 home water test strip,
immediately capturing an iPhone image of wetted strip
illuminated by overcast outdoor light,

... PPM estimates matching provided color chart:
iron 0
manganese 0.005
total hardness 10ppm ~ 0.6 grains per gallon
... but sediment, organics and microorganisms also impact UVT.

UV System size calculator based on UVT %/cm
UVT (transmission) vs UV254 (absorbance)
UVT assumes 254 nm unless noted otherwise 
UVT (%) = 100 * 10**(-UV254)
UV254 .001 au/cm ~ 99.77% UVT
Envig Gen4 (AKA WQM01H-4)
UV254 range: 0-0.2au/cm; resolution: 0.0001au/cm;
repetitiveness: 士0.001au/cm; accuracy:10% F.S. 
UV254 .02 (10% accuracy) ~ 95.5% UVT
"Buttons" do not move, offering no tactile feedback.
Included booklet titled AtomBit4

Yieryi sells Water Detective 4 with smartphone app.
LKBird 9-in-1 Smart Water Tester has better Amazon reviews than Envig,
but "buttons" on LKBird received did not work...
With Bluetooth app, but appearing identical to Envig,
product packaging lacked shrink wrap, which Envig had.

Units can hold 4 AAA cells, but install only 2,
since batteries in parallel are bad;
Voltages are never identical, and higher Voltage batteries
waste power driving current to lower, which do not want it.

12 Oct 2026 Water Detective 4 results with 20 micron sediment filter

  • TOC 2.2 total organic carbon; want < 1
  • COD 1.7 chemical oxygen demand; want < 1
  • TDS 158 total dissolved solids; want < 100
  • TURB 0.5 turbidity; want < 1
  • GH 5 hardness; RO is < 10
  • SAL 0 salinity
  • EC 319 electric conductivity; RO is < 100
  • TEMP 23.3 centigrade
  • UV254 0.0458 UV absorbance ~ 90% UVT
Readings are not saved over power cycle.

NSF validated systems rate flow based on 70% UVT
iSpring rates UVF8 max flow rate at 95% UVT

Fluorescent UV bulbs last a year and are a hassle to replace;
bulbs cost $50-80; ballasts cost $80
iSpring UVF50 LED UV Water Filter lasts 10+ years.
User manual access only by registered purchasers...?!
  installation video; no provision for cleaning...

PEX - support clamps
While Weaverville house plumbing is Polybutylene plastic,
plumbing around sediment filters is (better) PEX.
Plumb UVF50 into PEX using push (SharkBite) connections,
with unions and ball valve to facilitate occasional cleaning.
18 Oct: enough parts:

... but elbows < 90° have other plumbing far from parallel;
returning and ordering different and hopefully better elbows.
  • I:  PEX hangers

20 Oct:  still < 90 degrees, Derpipe elbows are works of art,
compared to other low cost cast stainless Amazon offerings,
with UV run near enough to parallel with sediment filter line:

21 Oct:  UVF50 plumbing parts assembly
Tested water for bacteria before starting; results in 48 hours.
iSpring video screws (1:25/3:23) metal NPT fittings
into UVF50 with neither pipe joint compound nor PTFE tape,
but printed instructions hand-tighten plastic nipples
to silicone seals, which I did, then applied to all others
both pipe joint compound and Megatape.
While male 1" to female 3/4" street elbows probably exist,
bushing/reducer adapted 3/4" street elbow to 1" union.
These unions use white polymer (PTFE?) seals,
measuring about 43mm o.d., 38mm i.d. and 2mm thick.

Megatape gets good reviews,
with no real consensus on how many wraps (I used 3).
Easier to work with than thinner regular white PTFE tape, after
applying pipe joint compound in thin layers to all male threads,
mainly to help stick Megatape first layer,
but being sure to fill bottoms of each thread,
having noted threads on returned street elbows were not sharp,
potentially leaving gaps that could slowly leak.

I had optimistically left all but one 14" pipe wrenches in Lexington,
which was silly, with pipe wrenches typically employed in pairs...
Most stainless fittings have flats for wrenches not sizes owned,
instead employing 12" and 18" crescent wrenches.
Pipe wrench and slip joint pliers were deployed for street elbows.

Timing bucket fill at sillcock yielded 7-8 gpm current flow;
1 micron filter should reduce that.


Done, but a royal pain

Temporarily suspended existing plumbing by packing straps,

then slipped plywood panels between plumbing and studs
to mount new plumbing.

iSpring's dry hand-tight fittings leaked A LOT.
Megatape and pipe joint compound cured those.
More problematic were union and shutoff valve leaks.
  • Both male and female shutoff valve threads are garbage,
    engaging other threads to only about half depth before seizing.
    Doubling Megatape layers reduced those leaks to very slow drip.
  • Fridays at Lexmark, we often visited Harbor Freight over lunch.
    This O-ring collection was one consequence:

    replacing PTFE 43x38x2mm seals with O-rings cured unions,
    at least for now...

    Having never before used them,
    I was anxious about SharkBite fittings, but they worked well.
    They do not resist twisting,
    and so far tolerated some without leaking.