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Providing Quality Backflow Services

We do our best to meet our residential and commercial customers backflow expectations. From testing to repairs and installation, we work with our customers to create the best possible outcome, while making sure that all of their needs are met both mechanically and financially.

ASSE Certified Backflow Testers.

When it comes to backflow testing in Pennsylvania, trust the expertise of our ASSE certified backflow testers. We understand the importance of maintaining a safe and compliant plumbing system. Our team is equipped with the knowledge and skills to ensure accurate testing and reliable results.

What is Backflow?

Backflow is a term in plumbing for an unwanted flow of water in the reverse direction. It can be a serious health risk for the contamination of potable water

What can cause Backflow?

There are two types of backflow conditions: back pressure and back siphonage. Backpressure: Occurs when the user system is at a higher pressure than the supply water systems allowing undesirable substances to be “pushed” back into the potable water system Back-Siphonage: Is caused by a negative pressure in a public water system or consumer’s potable water system. Back siphonage can occur when there is a stoppage of water supply due to nearby firefighting, a break in a water main, etc.

What can contaminate Drinking water?

While the most important chemical risks in drinking water arise from arsenic, fluoride or nitrate, emerging contaminants such as pharmaceuticals, pesticides, and microplastics generate public concern. Homes equip with fire suppression systems (sprinkler) often contain Glycol (Anti-Freeze) to prevent freezing.

What is Backflow Prevention?

The purpose is to prevent drinking water from being contaminated by other sources because of backflow.

Types of Backflow Preventers:

There are two common types of backflow devices used: a double check valve device and a reduced pressure zone device.

For All Your Backflow Needs... Call Us


Trusted Professionals.

At William J Millard Mechanical, we are proud to be licensed plumbers who prioritize professionalism and customer satisfaction. Our team is dedicated to delivering high-quality workmanship and exceptional service. When you choose us, you can trust that your plumbing needs are in capable hands.

How do we know which device we need?

High Hazard

A Reduce Pressure Zone Assembly (RPZA) backflow assembly must be installed if any of the below applies to the type of building and/or water usage at your facility.

  1. Aircraft and Missile Plants
  2. Automatic Car Wash
  3. Automated Manufacturing Plants
  4. Auxiliary Water Systems
  5. Breweries/Distillers
  6. Chemical Plants
  7. Dairies and Cold Storage Plants
  8. Dye Works
  9. Film Processing
  10. Irrigation System (non-residential)
  11. Laboratories
  12. laundires
  13. Meat Packing and Reduction Plants
  14. Metal Planting Plants
  15. Paper and Paper Products (wet process)
  16. Petrolieum or Gas Processing or Storage
  17. Planting Plants
  18. Power Plants
  19. Rubber Plants
  20. Sand and Gravel Plant
  21. Sewage or storm water treatment/processing
  22. Water Front Facilities and Industries
  23. Where a Cross Connection is to be maintained
  24. Radioactive Materials or substances, Processing Plants or Facialities Handling
  25. Manufacturing, Processing, and Fabrication Plants using Toxic Materials

Low Hazard

A Double Check valve Assembly (DCVS) backflow assembly must be installed if none of the above applies to the type of building and.or water usage at your facility.

Fire Service

  • If the system if dry or contains water only, a Double Check Detector Assembly (DCDA) must be used.
  • If the system contains any chemical additive (e.g. Antifreeze, etc), a Reduced Pressure Principle Detector Assembly (RPDA) must be used

Experience Staff

Bring to the table win-win survival strategies to ensure proactive domination. At the end of the day, going forward, a new normal evolved.

Based on true care & passion

Bring to the table win-win survival strategies to ensure proactive domination. At the end of the day, going forward, a new normal evolved.

Best hightect equipments

Bring to the table win-win survival strategies to ensure proactive domination. At the end of the day, going forward, a new normal evolved.

Comprehensive Backflow and Plumbing Services

We offer a comprehensive range of backflow services, including installation and repair. Whether you need a new backflow prevention device installed or your existing system requires repairs, our licensed plumbers are here to assist you. We prioritize the integrity of your plumbing system and the safety of your property.



Full Service Backflow

Let us keep you in compliance with all state and local testing regulations.Full Service company providing repairs and installation services for all types of consumers.

Full Service Backflow


Servicing all your plumbing needs, from new rough-in's, commercial and residential, fixture or valve replacements, pipe repairs and sewer line replacements we are here to help. Servicing Bucks and Montgomery counties.



William J Millard Mechanical has built a Commercial clientele that includes;
New Builds, Automotive repair chains, Retail Stores, Food Production Plants, Postal Facilities as well as Small Government Jobs.


Experience Backflow Services.
Master Plumber.

Experienced Master Plumber Offering Quality Backflow Services

With more then 25 years of experience William J Millard Mechanical has been servicing the Bucks and Montgomery Counties with pride and dedication.

With little more then word of mouth we have been successfully serving our communities plumbing needs and building a clientele that includes both residential and commercial businesses. We look forward to servicing all of your backflow needs.

Insured Plumbing Services in Pennsylvania

We understand the importance of peace of mind when it comes to your plumbing services. That’s why we offer insured plumbing services in Pennsylvania. With our team, you can have confidence in the reliability and safety of our work.

Backflow Tester.

Questions or Concerns?

Contact Us Today:

When you need reliable and trusted plumbing services in Pennsylvania, look no further than William J Millard Mechanical. We are committed to exceeding your expectations and ensuring your complete satisfaction. Contact us today to schedule an appointment or to learn more about our services.

Call us at : 267-980-4936