Norweco AT 1500 UV

Norweco AT 1500 UV Disinfection System Specs, Maintenance, and Ohio Septic Use

The Norweco AT 1500 is an ultraviolet disinfection unit used after advanced wastewater treatment. In Ohio, it commonly appears in approved Norweco treatment trains for spray irrigation, direct discharge, and NPDES-style systems where bacteria reduction is required before effluent leaves the system.

UV disinfection No chlorine addition Quartz sleeve Green light alarm Ohio NPDES
Ask about UV service Norweco parts hub NPDES guide
UV is the final disinfection step The upstream treatment unit still has to produce clear, properly treated effluent for UV to work.

Quick homeowner answer

The AT 1500 uses ultraviolet light to reduce bacteria in already-treated septic effluent without adding chlorine. It includes a UV lamp inside a quartz sleeve, a molded disinfection chamber, 4 inch inlet and outlet hubs, a control enclosure, current-sensing alarm logic, and a safety interlock for service. For Ohio NPDES or spray systems, it should be treated as part of the exact approved treatment train, not as a random add-on.

Core specs to verify

ComponentUltraviolet wastewater disinfection system
ConnectionsIntegral 4 inch inlet hub and 4 inch outlet hub
ElectricalDedicated 115 VAC single phase 15 amp circuit in Norweco manual
ControlsCurrent-sensing control circuit with green LED and alarm behavior
MaintenanceSix-month subassembly service and two-year lamp replacement recommendation
Related parts206C aerator, Bio-Kinetic filter, A20 re-aeration, Service Pro, pumps, and sampling point

Manufacturer performance data and flow envelope

The AT 1500 page needs to show the real disinfection envelope, not just "UV light." Norweco's brochure identifies NSF/ANSI Standard 385 certification, a 500 GPD evaluation loading, instantaneous flow testing from 0.18 GPM to 1.50 GPM, dual-pass UV exposure, 99.9 percent bacteria reduction language, and a two-year warranty. The installation manual adds the dedicated electrical and service details used by installers and service providers.

FieldAT 1500 published valueWhy it matters on site
CertificationNSF/ANSI Standard 385Shows the unit is not just a generic lamp in a pipe.
Evaluation loading500 GPDImportant when comparing the unit to the approved residential treatment train.
Flow envelope0.18 to 1.50 GPM instantaneous flowUV performance depends on exposure time, hydraulic path, and clear treated effluent.
Disinfection pathDual-pass flow past the UV lampThe chamber is designed to expose the effluent twice before outlet discharge.
Connections4 inch inlet and 4 inch outlet hubsConfirms the unit is part of the treatment train plumbing, not a small inline fixture.
Electrical115 VAC single phase dedicated 15 amp circuitPower, ballast, interlock, enclosure, and alarm behavior must be maintained.
Service intervalSix-month service check and two-year lamp replacement recommendationA green light is not a complete maintenance plan.
WarrantyTwo-year system warranty in brochureUseful for homeowners reviewing age, replacement, and service paperwork.
Low tested flow0.18 GPM

This is the low end of the instantaneous flow range stated in the Norweco brochure.

Evaluation load500 GPD

This is the residential loading context Norweco references for the six-month evaluation.

High tested flow1.50 GPM

This is the high end of the instantaneous flow range stated in the Norweco brochure.

Disinfection result99.9 percent bacteria reduction language

Actual compliance still depends on clear treated effluent, sleeve condition, lamp output, sample point, and the approved Ohio treatment train.

If bacteria sampling fails, the right question is not only "is the bulb on?" It is lamp age, quartz sleeve condition, current-sensing alarm status, upstream treatment quality, solids carryover, hydraulic loading, and whether the installed treatment train matches the Ohio approval.

Where the AT 1500 fits

The AT 1500 is not the primary treatment plant. It is a final disinfection step after upstream treatment, filtration, and settling. If solids, turbidity, poor treatment, or overloaded flow reaches the UV chamber, the lamp cannot fix the whole system. That is why UV alarms and bacteria sample failures should be diagnosed as a treatment-train problem, not only a lamp problem.

Ohio approval and NPDES context

What approval may include
  • Singulair or Singulair Green treatment unit.
  • AT 1500 UV disinfection.
  • Re-aeration when required by the approved configuration.
  • Sampling location, pump lock-out, telemetry, or Service Pro reporting.
  • Local health district operation permit and service records.
What homeowners should watch
  • Green indicator light off at the UV enclosure.
  • UV alarm reported through the control panel or service provider.
  • Failed bacteria or E. coli sample.
  • Visible solids, film, or dirty effluent entering the UV unit.
  • Water around the electrical enclosure or conduit.

Troubleshooting logic

1Check safe exterior statusLook for obvious breaker, disconnect, or visible alarm status. Do not open energized UV equipment without proper service training.
2Confirm lamp and interlockA green light off can mean lamp failure, current alarm, interlock misalignment, power loss, or wiring issue.
3Inspect the quartz sleeveA working lamp cannot disinfect properly through a fouled sleeve or dirty chamber.
4Review upstream treatmentSolids carryover, filter problems, high flow, or poor aeration can cause UV failure symptoms downstream.

Maintenance tips

  • Track lamp age and document replacement dates.
  • Ask the provider to inspect and clean the quartz sleeve during service.
  • Keep the control enclosure above finished grade and protected from surface water.
  • Do not bypass the safety interlock or look directly at an operating UV lamp.
  • If an annual sample fails, ask for lamp age, sleeve condition, upstream effluent observations, and sample location.

Internal links for the next decision

Ohio NPDES guideHow UV, sampling, telemetry, and permits work together. Bio-Kinetic filterFinal filtration and settling help keep solids out of the UV chamber. A20 air pumpReaeration can sit after UV in approved Ohio NPDES treatment trains. HB-105 pumpPressure pumping for spray, drip, and advanced dispersal after treatment. Septic maintenanceRoutine service records for lamps, alarms, samples, and controls. Norweco treatment salesProduct context for Norweco systems, treatment, and support.

Frequently asked questions

Does the AT 1500 need chemicals?

The UV disinfection process does not add chlorine or chemical disinfectant. Other system components may still have separate requirements depending on the design.

How often should the lamp be replaced?

Norweco's installation and operation manual recommends replacing the UV lamp every two years to maintain disinfection performance.

Why did the system fail bacteria sampling if UV is installed?

Common causes include a dead or weak lamp, fouled quartz sleeve, poor upstream treatment, solids carryover, hydraulic overload, or sampling problems.

Official sources

ManufacturerNorweco Model AT 1500
ManufacturerAT 1500 brochure
ManufacturerAT 1500 installation manual
OhioODH Norweco records
OhioOhio EPA HSTS general permit

Have a UV alarm or failed sample?

Send the UV enclosure photo, alarm status, lamp date, service report, and permit packet. BE Ohio can help decide whether this is a lamp issue, a sleeve issue, or an upstream treatment problem.

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