One of the most common calls we receive from homeowners is:
“My HSTP isn’t spraying. Is there something wrong with my system?”
The answer is: not necessarily.
Many homeowners assume their irrigation sprays should be operating all the time, but that’s actually not how most Home Sewage Treatment Plants (HSTPs) work.
Before you panic, let’s look at some of the common reasons your system may not be spraying.
First Things First – Is It Supposed to Be Spraying?
Most HSTP systems store treated water in a pump chamber until it reaches a predetermined level.
The system uses a float switch to activate the submersible pump once enough treated water has accumulated.
This means there can be periods where:
- no spraying is occurring
- the system appears inactive
- everything is actually working normally
If your household water usage has been low, the system simply may not have enough treated water to trigger a pump cycle.
Normal Reasons Your HSTP May Not Be Spraying
Low Water Usage
If you’ve been away, have fewer people staying at the property, or have generally used less water than usual, the system may not have accumulated enough treated effluent to activate the pump.
This is completely normal.
Recent Dry Weather
During dry periods, water usage patterns often change.
Some homeowners are surprised that their sprays don’t operate every day.
In reality, the pump only operates when sufficient treated water is available.
Reasons Your HSTP May Need Attention
Submersible Pump Failure
The most common reason an HSTP stops spraying is a problem with the submersible pump.
The submersible pump is responsible for pumping treated effluent from the pump chamber to the irrigation area.
If the pump fails:
- irrigation sprays may stop operating
- water levels inside the tank may continue to rise
- the alarm system will usually activate
Listen for a “Glugging” Sound
One of the tell-tale signs of a failed submersible pump is an unusual glugging, gurgling, or bubbling sound coming from the tank.
This sound often indicates that the pump chamber is becoming flooded and water levels are higher than they should be.
Many homeowners describe this as:
👉 “My septic tank is making a strange glugging noise.”
If you hear this type of sound, it’s worth having the system checked.
Moisture Around the Tank
Another common sign of a flooded pump chamber is unexplained moisture around the tank area.
You may notice:
- damp soil around the lid
- wet ground surrounding the tank
- unusually lush grass growth near the tank
While moisture can sometimes occur after heavy rain, persistent dampness around the tank can indicate that treated water is not being pumped away correctly.
Electrical Issues
Sometimes the issue isn’t the pump itself.
Potential causes include:
- power outages
- tripped circuit breakers
- faulty electrical components
These can prevent the submersible pump from operating even though the pump itself may still be functional.
Blocked Irrigation Lines
Although less common, irrigation pipework or spray heads can become blocked or damaged over time.
This may result in:
- reduced spray performance
- uneven distribution
- little or no visible irrigation
What About the Alarm?
Most HSTP systems are fitted with alarms for exactly this reason.
If a pump fails or water levels become too high:
👉 the alarm should activate.
At Maxfield’s Wastewater, alarm systems are tested during every service to ensure they are functioning correctly.
The alarm is designed to provide an early warning before a small issue becomes a major problem.
Heavy Rain Can Also Affect Spraying
During periods of heavy rain:
- groundwater levels can rise
- stormwater can enter older pipework
- water levels within the system can increase
Sometimes the alarm may activate while the system works to catch up.
If your irrigation sprays are operating during this period, that’s generally a good sign.
It means the pump is actively working to reduce water levels.
Once conditions return to normal and excess water is dispersed:
👉 the alarm should usually reset itself.
Signs You Should Contact a Service Technician
If your HSTP isn’t spraying, keep an eye out for:
✔ An active alarm
✔ A strange glugging or gurgling sound from the tank
✔ Moisture or wet ground around the tank
✔ Unusually high water levels inside the tank
✔ Ongoing odours
✔ Irrigation sprays that have stopped operating completely
These are all signs that the system may require attention.
Why Fast Repairs Matter
If a submersible pump or electrical component fails, quick repairs help prevent:
- extended downtime
- high water levels
- unnecessary stress on the system
That’s why Maxfield’s Wastewater carries:
✔ submersible pumps
✔ aerator pumps
✔ common replacement parts
✔ components for multiple HSTP brands
on our service vehicles every day.
In many cases, we can diagnose and repair the issue during the same visit.
We Service All Major HSTP Systems
Our team services a wide range of systems throughout Moreton Bay, including:
- Taylex
- Biocycle
- Fuji Clean
- Aqua Nova
- Envirocycle
- Earthsafe
- Ecosafe
- Clearwater
- And many more
No matter what brand you have, we can help determine why your system isn’t spraying.
Speak with Jamie
If your HSTP isn’t spraying and you’re unsure whether it’s normal or a sign of a problem, we’re here to help.
At Maxfield’s Wastewater, we provide professional servicing, repairs, and advice across the Moreton Bay region.
Contact Maxfield’s Wastewater and speak directly with Jamie.
Maxfield’s Wastewater
Local. Reliable. Done Right.
