5.3104.15 Controls—Underground Leak Detection

Hydronic Heating (Hot Water and Steam)
Equipment Maintenance, Testing, and Repair
Desired Outcome: 
Monitor underground leaks for quick corrective actions
Hazardous materials

Materials containing asbestos will be dealt with in accordance with SWS 2.0110.2 Potential Asbestos-Containing Materials

Hazardous materials will be handled in accordance with applicable local laws and codes before work begins

Ensure safe environment and work place

Installation of underground leak detection system

If steam piping is insulated, assess for presence of asbestos-containing materials (ACMs) prior to disturbing the material; if confirmed not to be an ACM ACM Asbestos-containing material , then proceed with the following:

  • Insulation will be removed from the piping where monitoring sensors or gauges will be installed
  • Control sensors or gauges will be installed no more than 5' upstream and downstream of point of pipe entry and exit into and out of the ground, respectively
  • Control sensors and gauges will be installed with anti-siphon piping with pet cocks
  • Control sensor will be wired back to controller
  • Wiring will be in accordance with manufacturer specifications and all applicable codes
  • Pressure gauges will be installed such that the display face plate is facing in the direction that is easy to read without need of ladder
  • Service valves will be installed for isolation and ease of maintenance, repair, and replacement of control sensor or gauges
  • Drain valves will be installed between the isolation valves to drain the left over medium during repairs and maintenance

Ensure the control sensors or pressure gauges are installed to allow leak monitoring

Testing and verification

A pressure differential (Δp) chart will be established at various load conditions, which will be used as benchmark to monitor leak

A complete installation and operation and maintenance manual will be provided to the property manager/occupant

Confirm system capabilities and functionalities


Building/property management team and building operations staff will be trained on use of control or gauges to monitor leak and regular maintenance procedure

Multiple laminated copies of the pressure differential chart will be provided to building/property management team for filing and posting near sensor and gauge installation location

Protocols will be set for someone from the building operations staff to record the readings on a regular basis, and the management staff to review and file the logs

Management will call for corrective actions as soon as problem is identified

Educate client on best use