Sewer Stack Alarm

Sewer Stack Alarm


  • Simple to install and requires just a 3/8in BSP thread
  • Operates by detecting high stack level inside a side branch which overcomes scaling issues
  • Operates up to 6-Bar with integrated gas pressure vent
  • No Software
  • No Programming
  • Wireless range 50 to 150m in buildings
  • Battery operated
  • Installs into pipes of any 10cm and greater


  • Sewer stack alarm for open/vented stacks
  • Hot stacks (those carrying radioactive isotopes from cancer wards)

The Challenge

Sewer stacks and drainage down pipes, especially those from rooftop gardens can block and cause flooding and damage to a building and its contents. Further, a blocked stack can pose a health hazard especially if the stack carries contaminated waste or radioactive isotopes from perhaps a hospital’s cancer ward.

Our Solution

RDN’s sewer stack monitoring system is highly cost-effective and easy to install on both vertical and horizontal stacks and can be deployed as a stand-alone system or interfaced via our Gateways to the building’s BMS system. Each system comprises a stack adapter that is inserted into the stack, a stack condition detector/transmitter, and a receiver.

The Sewer Stack Level Monitor is battery-operated making it easy and safe to install in ducts and risers. Its wireless technology eliminates the need for cables between the stacks and the receiver / BMS interface.  Supplied as DIY kits, the systems can be installed in a matter of minutes and up and running in under an hour.  Systems can be created to monitor a single stack or up to 4 stacks in a single location.

Receiver options include our Sentinel Receiver and our BMS Gateway.  The Sentinel can provide up to 4-zones of protection and provides status LEDs and an audible warning. Whereas the Gateway is for installation in service ducts and risers and provides individual relays for each of the stacks being monitored enabling the BMS system to be programmed to display the individual stack conditions.