Biological treatment plant alarm: what it means and what to do

The most common causes of an alarm

AUGUST controller lights

The AUGUST AT technical passport describes the signals as follows:

• a steady green light means the compressor has been stopped temporarily; this is not a fault;
• a flashing green light means the compressor is running;
• a steady red light means the compressor or an auxiliary device is disconnected or faulty;
• a flashing red light with a sound means a power failure. The signal can go on for several hours, as long as the battery lasts. When power returns, the controller switches on after 2 minutes.

Reminders can also appear on the display: REPLACE FILTER (after six months the compressor filter must be cleaned or replaced) and CHANGE MEMBRANE (after a year the membrane must be replaced). The passport provides that if the controller fails, the compressor can be disconnected from the controller and plugged straight into the mains so that the plant keeps getting air. Under the passport, inspection and maintenance are carried out by AUGUST specialists or authorised representatives.

The AQUABLOC control unit

The AQUABLOC control unit checks the condition and connection of the compressor, the valve module and the work cycle by itself at least once a day. The audible alarm sounds only between 8:00 and 20:00; pressing any button silences it for 24 hours if the fault persists. Built-in service timers remind you about maintenance: for the plant after 365 days, for the compressor after 7,000 working hours.

What to do in the first few hours

1. Read the message Take a photo of the display or write down which light is on and how.
2. Check the power Look at the circuit breaker in the distribution board, and check the socket and the extension cable, if there is one.
3. Listen to the compressor Is it humming? Is it too hot, or is there unusual vibration? According to the PURA passport, these things should be checked regularly.
4. Open the lid There should be fine bubbles in the aeration chamber. If there are none, or the level is close to overflowing, the problem is serious.
5. Use less water While the plant isn't working, every litre leaves untreated or raises the level.
6. Don't switch programmes The AUGUST passport states that changing the programme often is not recommended. It won't fix a technical fault.
7. Send a request Give the manufacturer, the model, the message on the display and when the plant was last serviced.

Why you must not ignore an alarm

When the compressor stops, the plant stops treating, and poorly treated water leaves through the outlet into a ditch or the ground. National regulations require the owner of a BIO plant to ensure that the sludge is active and that there are no conditions that worsen treatment, and to carry out extraordinary maintenance after a breakdown. A copy of the maintenance document must be submitted to the keeper of the register within a month.

The most common repairs

• replacing the compressor membrane (AUGUST provides for it once a year);
• cleaning or replacing the air filter (AUGUST: every 6 months);
• replacing the compressor if it overheats or doesn't build up pressure;
• replacing the float switch or the discharge pump;
• cleaning clogged airlifts and pipes;
• pumping out surplus sludge if there is too much of it.

Read more about the work in biological treatment plant repair. Maintenance of specific models: AUGUST AT-6, PURA.

How much it costs

Routine BIO plant maintenance costs from €160. The cost of a repair depends on what needs replacing: the membrane, the compressor, the pump or the control unit. Give the model and the message on the display in your request, and we can tell you an approximate price before we travel out.