An aerated wastewater treatment system (AWTS) relies on bacteria that need oxygen to break down sewage. The air blower pumps air into the treatment chamber around the clock to keep them alive. When it stops, the system can turn septic, start to smell and stop treating properly, so a failed blower is something to replace quickly.
The septic air blower PSA stocks is the Hyjet HAP, a compact diaphragm air pump for aerating wastewater in residential and commercial sewage treatment systems.
The three sizes
| Model | Airflow | Price |
|---|---|---|
| HAP-80 | 80 L/min | $721.55 |
| HAP-100 | 100 L/min | $809.55 |
| HAP-120 | 120 L/min | $914.05 |
Per the listing, all three have an aluminium alloy housing rated IPX4, a duplex diaphragm design that doesn't need oil lubrication, and double damping for low noise.
Match the airflow to the system
The single most important thing is the airflow your treatment system is designed for. You'll usually find it on the old blower's label, in the system's manual, or from the manufacturer or your service agent.
- Too little air and the bacteria can't keep up. Treatment suffers and the system can start to smell.
- Too much air can over-agitate the chamber, push solids through and waste power. It can also exceed the system's diffuser rating.
Match the original blower's L/min as closely as you can. If it was rated at a figure between the HAP sizes, check with your system manufacturer or service agent which way to go.
Check the pressure too
Airflow is only half the rating. The blower also has to overcome the water depth above the diffusers. A blower's output falls as back pressure rises, so a deep chamber needs a blower that delivers its airflow at that depth. Check the HAP datasheet (under Downloads) for its airflow at different pressures, and compare it to your system's requirement.
Installing and looking after it
- Keep it dry and ventilated. IPX4 protects against splashing, not sitting in water. Mount it off the ground, out of pooling water, with airflow around it for cooling.
- Keep the air intake clean. A blocked intake filter cuts airflow and makes the blower work harder.
- Use the right power. It runs continuously, so it should be on a properly installed weatherproof outlet. A licensed electrician should do any hard-wiring.
- Diaphragms wear. Diaphragm blowers are reliable, but their diaphragms are a wear part. A blower that's getting louder or delivering less air is often due for diaphragm service.
- Your service obligations. In most states, an AWTS must be serviced by an accredited service agent on a set schedule, and some councils require their approval for changing major components. Check your service agreement and council requirements before replacing the blower yourself.
For high level alarms on treatment and pump tanks, see Level Alarms. The HAP range is available to order on backorder; contact PSA to confirm lead time.
Frequently Asked Questions
What size septic air blower do I need?
One that matches the airflow your treatment system is designed for, usually shown on the old blower's label or in the system manual. Hyjet HAP blowers come in 80, 100 and 120 L/min.
What happens if my septic blower stops?
The bacteria that treat the wastewater lose their oxygen supply. Treatment suffers and the system can start to smell, so replace a failed blower promptly.
Does the Hyjet HAP need oil?
No. It's a duplex diaphragm design that doesn't need oil lubrication.
Can I replace my AWTS blower myself?
Check your service agreement and council requirements first. Many councils require an accredited service agent to service the system, and some require approval for changing major components.