Boiler Inspection, Certification & Backflow Testing

Boiler Certification & Backflow Testing
Certified Boiler Services

Our experienced technicians provide professional boiler inspections, maintenance, repairs, and certification services to help ensure your boiler system operates safely, efficiently, and in compliance with local regulations. Whether you need routine maintenance or certification for a commercial facility, we deliver dependable service you can trust.

Backflow Testing & Certification

Protect your drinking water with certified backflow prevention testing. We inspect, test, repair, and certify backflow prevention assemblies for residential, commercial, and industrial properties. Our team ensures your system meets all local water authority requirements and provides the necessary documentation upon completion.

Our Services Include:
Annual Backflow Prevention Testing
Backflow Device Repairs & Replacement
Backflow Certification
Boiler Inspections & Certification
Boiler Maintenance & Repairs
Commercial & Residential Service
Compliance with Local and State Requirements
Fast Scheduling & Reliable Service
Professional plumber inspecting residential water heater system and copper pipes in organized basement utility space

Standard Backflow Testing (½" Assemblies)

Our standard backflow testing service is designed for residential and small commercial properties with ½-inch backflow prevention assemblies. The service includes a complete performance test, inspection of the device, and submission of the required test results to your local water authority (where applicable).

$160

per certification


Certified backflow performance test

Visual inspection of the assembly

Compliance documentation

Prompt and reliable service

Large Backflow Assembly Testing (1" and Larger)

Large Backflow Assembly Testing (1" and Larger)

Larger commercial and industrial backflow prevention assemblies require additional testing and inspection due to their size and complexity. We service 1-inch and larger assemblies to ensure they are operating properly and remain compliant with local regulations.

$180

per certification


Certified testing for larger assemblies

Compliance paperwork

Commercial and industrial service available

Performance verification

Commercial mechanical room with industrial water heater, complex piping systems, and technician performing maintenance inspection

Permit to Operate

Many jurisdictions require a Permit to Operate before certain boiler or backflow systems can legally remain in service. We can assist with obtaining the required permit, completing the necessary inspections, and ensuring your equipment meets local compliance requirements.

$335

per certification


Permit application assistance

Required inspection coordination

Compliance documentation

Guidance throughout the approval process

Professional plumber inspecting residential water heater system and copper pipes in organized basement utility space

Backflow Certification

Need proof your backflow device has passed inspection? We provide official Backflow Certification documentation for property owners, businesses, HOAs, and municipalities after successful testing.

$160

per certification


Official certification documentation

Compliance records

Documentation accepted by most local water authorities

Schedule Your Service Today

Whether you need annual testing, certification, or assistance with permits, Interlock Plumbing is here to help. Contact us today to schedule your boiler certification or backflow testing appointment.✔ Certified Technicians
✔ Fast Scheduling
✔ Residential & Commercial Service
✔ Honest, Upfront Pricing