Econocycle AWTS: An Owner’s Guide to the ECO PRO and Twin Tank Systems

An Econocycle is an aerated wastewater treatment system (AWTS) made by Eco-Septic Pty Ltd at Warragamba, west of Sydney. In NSW it comes as the single-tank ECO PRO, in concrete or poly, or as a two-tank nutrient-reduction (NR) model, and all four are accredited by NSW Health for households of up to 10 people.

If there’s an Econocycle lid in your yard, the basics match any AWTS: a service every three months by an authorised agent, a report to council after each visit, and a desludge every few years. What’s specific to this brand is the detail. Which certificate covers your model, what the warranty really covers, what to do when the power drops out, and whether the UV option applies in NSW at all.

This guide sticks to what the NSW Health certificates and Econocycle’s own manuals and pages say, checked on 28 September 2026. For how Econocycle sits against Biocycle, Ozzi Kleen, Bioseptic and the rest, see our AWTS brands comparison.

Which Econocycle models are on the NSW register

NSW Health lists Eco-Septic Pty Ltd under two trading names at the same Warragamba address: Econocycle and BioCycle. Each name has its own model names and certificate numbers, but the specifications match: the Schedule 1 description on each Econocycle certificate is identical to its BioCycle counterpart (ECO PRO Concrete and BioCycle Pro Concrete 1500, STS-AWTS041 and 075, for example), and each pair was issued on the same day. They remain separate accreditations, so use the certificate number your council approval names. Here’s the Econocycle side.

Each blower is specified at a nominal 80 litres of air a minute. “Or equivalent” matters: the certificate lets a service agent fit a different blower or pump as long as it meets the accredited specification, so the brand on your blower may not match the table.

You’ll also see an Econo Tallboy on Econocycle’s website. The company describes it as the Econo Pro built into a different tank to get a deeper inlet (an invert of 700 mm plus) without risers. It isn’t listed under its own name on the register, so if you have one, ask Econocycle or your council which certificate your approval sits under.

Older units and the owner’s manual often say Eco Septic rather than Econocycle. The certificate number on your council approval is the reliable way to tell what you have.

How the four-stage process works

Econocycle describes the ECO PRO in four steps, and the certificates fill in the numbers.

Primary settlement. Everything from the house enters the septic zone first. Solids settle, fats and scum float, and anaerobic bacteria start breaking the waste down. In the single-tank ECO PRO this chamber is 3,000 litres, partitioned 2:1.

Aeration. Liquid moves through a transfer port into the aeration chamber, where the blower pushes air through two aeration legs near the floor. Inside is growth media, plates that give aerobic bacteria a large surface to live on. It only works while air keeps flowing.

Clarification. In a calmer chamber, the remaining solids settle out. Two airlift devices, run off the same blower, return that settled material to the primary chamber. The owner’s manual says this return also keeps a food supply rich in microbes cycling through the system during periods of low flow.

Disinfection and irrigation. Clarified water passes a chlorinator and drops into the final chamber, where a submersible pump sends it out to the irrigation area. The certificate requires that pump to deliver at least 2 cubic metres an hour at 7 metres of head.

Two features are worth knowing. The single-tank certificates list 1,285 litres of emergency storage, built in by raising the chamber walls, which is the buffer that buys you time in a blackout. And the alarm panel lights air faults and water faults separately, each with a 24-hour mute.

Chlorine or UV: what applies in NSW

Econocycle’s product pages for the Econo Pro, Tallboy and Twin Tank all say treated water “undergoes chlorination or UV disinfection”. For an NSW install it isn’t that simple.

All four NSW Health certificates we opened describe the same thing: a chlorine disinfection unit installed on the outlet of the clarifier. The ECO PRO Concrete certificate’s conditions then say the system must be supplied and installed in line with the accredited design, “including the disinfection unit”, and can’t be modified other than swapping pumps and similar components for equivalents. A permanent change to the design has to go back to NSW Health for a variation.

So if you’re buying a new Econocycle in the Hunter and UV appeals, ask Econocycle in writing whether a UV configuration is accredited for your model in NSW, and check your council will approve it, before anything goes in the ground. For an existing system, assume chlorine unless your approval paperwork says otherwise.

On the chlorine itself, Econocycle says it uses a special grade of chlorine compound that breaks down quickly once it reaches the garden, and that it’s the only chemical in the process. The manual is blunt about substitutes: use no sanitising agents other than those the manufacturer recommends, because dangerous chemical reactions can occur. Tablets are replenished at each quarterly service, and the ECO PRO certificate requires free residual chlorine in the final effluent of more than 0.2 and less than 2.0 mg/L. How fast tablets go, and why, is covered in how often AWTS chlorine tablets need replacing.

Warranty terms, as published

Econocycle’s warranty page gives two periods: 15 years on tanks, and 2 years on the pump, electrics, internals, pipework and fittings, both from the date of purchase. New tank buyers also get two free services, according to the home page.

The conditions are where owners get caught. As published on the warranty page and in the owner’s manual:

• The parts guarantee applies to defects notified within 24 months of installation, and only while the system is under a continuous service agreement with Eco Septic or an authorised service agent.
• Repair or servicing by an unauthorised provider voids it.
• Normal wear on perishables such as filters and seals isn’t covered.
• Damage from power surges, floods, electrical storms, incorrect power supply, insects or vermin, and domestic animals or wildlife is excluded.
• Freestanding tanks that aren’t buried aren’t covered.
• The warranty covers the original purchaser only and isn’t transferable.

That last point matters if you’ve bought a property with an Econocycle already in the ground. Whatever warranty the builder or previous owner had doesn’t pass to you, so a failed blower in year three is your cost either way. A pre-purchase septic inspection is the time to find out what condition the blower, pump and chlorinator are in.

NSW Health’s certificate expects 5 years of service life from mechanical and electrical parts and 15 years from everything else. So a blower or pump that fails after year two is outside the parts warranty but still inside its expected service life, and the repair is on the owner.

Servicing an Econocycle: what the certificate requires

The certificate conditions are clear. You must hold a service contract or agreement of at least 12 months, the system must be serviced every three months, and the agent must be employed or authorised by the manufacturer, use parts that meet the accredited specification, and send the NSW Health Local Council Service Report to your council immediately after every service. Owners can’t service it themselves.

At a minimum, each quarterly visit has to check:

• the chlorinator, with the disinfectant topped up
• the irrigation pump and air blower
• the alarm system
• slime growth on the filter media
• the sludge return
• the irrigation area
• free residual chlorine, pH and dissolved oxygen, tested on site

Econocycle’s own service sheet adds testing the alarm and high-water float, cleaning the blower filter and monitoring sludge levels. Call-outs between services for breakdowns or flooded units aren’t in its contract, and parts and labour cost extra.

Econocycle units are on the list of brands we service in the Hunter. Our AWTS servicing runs $90 to $150 a visit, $360 to $600 a year, including the chlorine top-up, sludge check, blower filter clean and the council report. If your system is still inside its 2-year parts warranty, check with Econocycle before changing agents, since the warranty depends on an authorised agent doing the work.

Pump-outs are separate, and timing matters

The manual says pump-out “is not a standard service procedure” and costs extra. Your service agent tells you when a desludge is due. A full AWTS desludge and pump-out with us is $450 to $750, typically every 3 to 5 years.

The manual also carries a warning that suits the Hunter: never pump out in wet weather or soon after, because of the risk of the tank floating. An emptied tank in saturated ground can lift, and the poly ECO PRO weighs only around 500 kg empty, according to its owner’s manual. On heavy clay blocks around Maitland, Cessnock and Kurri Kurri, or low-lying ground near the Williams and Hunter rivers, we’d rather reschedule a routine desludge after a big wet than risk it.

Power cuts, blower restarts and alarms

This is the section of the owner’s manual worth sticking on the fridge.

Leave the power on. The manual says to keep power on at all times, holidays included. If the system won’t be used for more than a month, it asks you to let Eco Septic know and leave a contact name.

After a blackout, check the blower. When power comes back, walk out and listen for the hum. The manual’s instruction if it hasn’t restarted is to switch the power off again for 10 minutes, then turn it back on. The troubleshooting table also says to allow 30 minutes after a power interruption for the system to catch up.

During a long outage, go easy on water. If power is off for an extended time, the manual gives 8 hours as an example, keep water use to a minimum. You can still flush and wash dishes, but keep showers short. An alarm may come on after an extended blackout as levels rise, and it should settle some time after power returns. If the power is off too long, the manual warns, the bacteria die off and the system will need a pump-out.

When the alarm sounds. Mute it with the 24-hour button, then look at which light is on. The panel separates high water from loss of air, and the manual notes the system will usually keep working acceptably for several days while a fault is found. A general rundown of what sets off AWTS alarms is in why your AWTS alarm is beeping.

Common Econocycle faults and what they usually mean

The manual’s troubleshooting table is short, but it lines up with what goes wrong on most aerated systems.

Air light on. Loss of air means the blower has stopped or isn’t delivering enough air. Clear the blower filter if one is fitted, check the power, and listen for the hum. A tired blower can sometimes be fixed with a diaphragm service kit ($120 to $250). If it’s past that, a replacement blower is $650 to $1,400 installed; the full breakdown is in AWTS air blower replacement cost. Keep in mind that surge and storm damage is excluded from the warranty.

Water light on. High water means effluent isn’t leaving the final chamber fast enough. The manual’s first check is the irrigation line: make sure the line and outlets are clear and not kinked or restricted. After that it’s the pump or its float switch. Under our repair-first approach, a faulty float switch is a $250 to $650 fix. A failed submersible pump is $600 to $1,200 installed.

Offensive smell. The manual suggests checking the blower is running and ruling out another source first: dry floor wastes, damaged or low vents. A sour smell from the tank itself usually means aeration has stopped or something has killed the bacteria, such as bleach, strong antibacterial cleaners, pesticides or unused medicines, all of which the manual says to keep out.

Any hard-wired electrical work has to be done by a licensed electrician; the certificate makes that a condition. If an alarm is sounding with the tank close to overflowing, that’s a same-day or next-morning job for us: call 0468 278 123.

Looking after the irrigation area

The ECO PRO certificate allows spray, mulched surface drip, subsurface drip at around 100 mm, or subsoil application, whichever your council approved. The manual says treated effluent should not go on vegetables or fruit and the area shouldn’t be used for recreation. Planting it cuts down wet patches; the manual’s list includes callistemon, grevillea, hardenbergia, kikuyu and buffalo grass.

Frequently Asked Questions

Who makes Econocycle systems?

Econocycle systems are made by Eco-Septic Pty Ltd at Warragamba in NSW. The NSW Health register lists the same company under two trading names, Econocycle and BioCycle, each with its own model names and certificate numbers, though each Econocycle certificate carries the same specification as its BioCycle twin. Older units and the owner’s manual often carry the Eco Septic name.

Is an Econocycle AWTS approved in NSW?

Yes. As at 28 September 2026, the NSW Health register lists four Econocycle-side models for 10 persons each: the ECO PRO Concrete and Poly (certificates STS-AWTS041 and 051, expiring 31 December 2029) and two Twin Tank NR models (STS-AWTS077 and 078, expiring 31 December 2030). Your council still has to approve the individual installation.

Can an Econocycle use UV instead of chlorine?

Econocycle’s product pages mention chlorination or UV disinfection, but the four NSW Health certificates we checked describe a chlorine disinfection unit, and the ECO PRO Concrete certificate says the system must be installed to the accredited design including that unit. Before choosing UV for an NSW install, get written confirmation from Econocycle that it’s accredited for your model and check with your council.

What does the Econocycle warranty cover?

Econocycle publishes a 15-year warranty on tanks and 2 years on the pump, electrics, internals, pipework and fittings. It depends on a continuous service agreement with an authorised agent, excludes flood, storm and power surge damage and normal wear on filters and seals, and applies to the original purchaser only, so it doesn’t transfer when a property sells.

What should I do if my Econocycle blower stops after a power cut?

Econocycle’s owner’s manual says to check the blower is running once power is restored. If it hasn’t restarted, switch the power off again for 10 minutes and then turn it back on. If it still won’t run, mute the alarm, keep water use low and call your service agent.

How often does an Econocycle need servicing?

Every three months, by a service agent employed or authorised by the manufacturer, under a service agreement of at least 12 months. That’s a condition of the NSW Health certificate, and the agent sends a Local Council Service Report to your council after each visit. Desludging the primary chamber is separate and usually needed every 3 to 5 years.

Sources and further reading

• NSW Health, Register of accredited aerated wastewater treatment systems: Eco-Septic Pty Ltd trading as Econocycle and as BioCycle, model names, certificate numbers, person ratings and expiry dates, checked 28 September 2026.
• NSW Health, Certificate STS-AWTS041, EcoSeptic EcoPro Advanced Concrete AWTS: chamber capacities, emergency storage, chlorine disinfection unit, blower and pump specification, 24-hour alarm mute, service life, servicing conditions, effluent standard and permitted irrigation methods.
• NSW Health, Certificate STS-AWTS051, EcoSeptic EcoPro Advanced Poly AWTS: 7,200 L poly tank, chlorine disinfection and blower specification.
• NSW Health, Certificate STS-AWTS077, EcoSeptic Twin Poly Advanced NR AWTS and STS-AWTS078, Twin Concrete: two-tank NR design, chlorine disinfection and Hiblow HP80 or equivalent blower.
• NSW Health certificates STS-AWTS075, STS-AWTS076, STS-AWTS079 and STS-AWTS080: the BioCycle certificates, compared pair by pair with the Econocycle ones.
• Econocycle, Econo Pro, Twin Tank System and Econo Tallboy: four-stage process, the chlorination or UV wording, and the Tallboy’s deeper inlet.
• Econocycle, How does it work: sludge return to the first chamber, chlorine as the only chemical used, tablets replenished at quarterly services.
• Econocycle, Warranty and home page: 15-year tank and 2-year parts warranty, exclusions, non-transferability, two free services with a new tank.
• Eco Septic Poly Owners Manual (PDF): power and blower restart advice, alarm troubleshooting, do’s and don’ts, pump-out and wet-weather flotation warning, irrigation planting, service checklist, warranty conditions and the approximate 500 kg poly tank weight.
• Econocycle, Service Maintenance Work (PDF): the manufacturer’s quarterly service checklist and what its contract excludes.