Backflow Prevention
Backflow Preventer Installation & Testing
Protect your home’s drinking water from contamination. With code-compliant installation, annual testing, and reliable service.
Protect Your Drinking Water
One-Way Protection for Clean Water
A backflow preventer is a one-way barrier that stops dirty water from being pulled backward into your clean water supply. When pressure changes in the system, water from a hose, irrigation line, boiler, or other source can be siphoned into your drinking water. And a working backflow preventer is what stops that. Devices range from simple hose-bib vacuum breakers to reduced pressure zone (RPZ) backflow preventer valves, and we install and service them all.
Maryland code requires testing on certain backflow devices annually. We install, test, and maintain these devices to keep your home compliant and your water safe.
Annual testing confirms internal seals and valves are working properly. Mineral buildup, pressure-related wear, and age all degrade these devices over time. And a failed device offers no protection at all.
- New backflow preventer installation
- Annual testing and certification
- Device replacement
- Sprinkler and irrigation backflow preventer valves
- Boiler and commercial equipment
- Compliance documentation
What We Offer
Our Services
Installation
Code-compliant installation of RPZ (reduced pressure zone) and sprinkler backflow preventer valves for irrigation systems, boilers, and any cross-connection that requires protection.
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Annual Testing
Required yearly inspection by a licensed tester. We test, certify, and submit documentation as needed.
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Replacement
When testing fails or a valve is past its life, we replace it with a modern, code-compliant unit and provide an upfront estimate before any work begins.
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Signs Your Backflow Preventer Needs Service
01
Reduced water pressure in the home
02
Unusual taste or odor in tap water
03
Moisture or leaks around the device
04
Failed annual test results
05
More than a year since last inspection
06
Visible wear or corrosion on the unit
Why Homeowners Choose Metcalf
$0
Commissions
Our plumbers are paid hourly. They have zero incentive to upsell you.
23+
Years
Over two decades serving Baltimore-area homeowners.
Same-Day
Response
Fast response times because we know plumbing emergencies can’t wait.
4.9
Stars
Hundreds of five-star reviews from satisfied customers.
Backflow Devices
Why Maryland Requires Backflow Preventers
Maryland plumbing code (and most county/utility requirements) mandates backflow prevention on commercial properties, irrigation systems, fire suppression, and many residential setups. Here’s why. And where they’re required.
Protect Drinking Water
Backflow devices stop contaminated water from being siphoned back into the public supply during a pressure drop.
Required Annually
Most counties require annual testing by a certified backflow tester. We’re certified and file your reports for you.
Common Install Locations
Lawn irrigation, fire sprinkler risers, commercial buildings, hose-bib vacuum breakers, and boiler feed lines.
Good to Know
Frequently Asked Questions
What is a backflow preventer?
A valve that stops used or contaminated water from reversing back into your clean drinking supply. Protecting your household and the public water system.
Do I need a backflow preventer?
If you have irrigation, a boiler feed, or run a commercial property, you likely do. Many jurisdictions require them.
What’s the difference between a preventer and backflow testing?
The preventer is the device; backflow testing is the annual certification that confirms it still works.
How often should it be inspected?
Annually in most jurisdictions. And after any repair. We handle both installation and certified testing.
Do you install and repair backflow preventers?
Yes. From our shop in Catonsville, we size, install, and repair them for homes across Baltimore and Howard County, then test to confirm compliance. Call (410) 242-3111.
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