Not every backflow preventer is tested the same way. We identify your device type, run the procedure that matches it, record the readings and send the results to your district.
- Price$105 flat
- TimeUnder an hour
- SchedulingSame week
- FilingIncluded
Pricing
| Backflow size | Flat fee per backflow |
|---|---|
| Under 4" | $105 |
| 4" and larger | $175 |
Includes the test and filing with your water district. No hidden fees.
Want to get on the schedule? Call or book online.
Types we work on
- RP assemblies on commercial and high-hazard lines
- Double checks on fire lines and lower-hazard services
- PVBs and SVBs on irrigation
- Detector assemblies on fire sprinkler services
Testing reduced pressure (RP) assemblies
RP assemblies, sometimes written RPZ, protect connections where the risk is highest: chemical feeds, medical equipment, boilers, car washes and similar uses. Inside are two check valves and a relief valve in the middle that opens to the air if pressure between the checks gets too close to the supply pressure.
When we test an RP, we measure when that relief valve opens and whether each check valve holds. Those readings go on the report your district reviews.
A dripping or spitting relief valve between tests usually means debris or wear on the first check. We note it on the visit and explain whether it needs attention now. Catching it early tends to be cheaper than waiting for a failed test or a valve that won't stop discharging.
Testing double check valve assemblies
Double check valve assemblies use two check valves back to back. There's no relief valve, so they're used where the hazard is lower, such as many fire sprinkler services and some landscape and building lines.
Testing one means checking each valve separately. The tester closes the shutoffs, connects the gauge to the test cocks and confirms both checks hold.
These devices are often in underground boxes or vaults. If yours tends to collect water, mud or critters, mention it when you schedule. We'll bring what we need to clear it out so the test can go ahead on the same trip.
Vacuum breakers on irrigation lines
PVBs and SVBs are common on residential and commercial irrigation. They're the above-ground devices with a bonnet on top, usually near the sprinkler valves. Their job is to stop water from being siphoned back out of the sprinkler lines when pressure drops on the supply side.
The test checks two things: that the air inlet opens and that the check valve holds tight. It's quick, and these are often the easiest devices to reach.
Placement matters with these. They need to be above the highest downstream sprinkler or outlet to work as designed. If yours looks too low, we'll tell you, because a device can pass its readings and still be installed wrong.
Testing devices on fire sprinkler services
Many commercial and multi-unit buildings have a double check detector assembly (DCDA) or a reduced pressure detector assembly (RPDA) on the fire sprinkler line. These have a small bypass with a meter that shows if water is being used on the fire line when it shouldn't be.
We test the main assembly and the bypass assembly, since both protect the water supply. Fire line devices are often 4 inches or larger, which falls in the $175 per device price tier.
Fire systems usually involve more than one party: the building owner, the fire sprinkler contractor and sometimes the fire department. Closing valves on a fire line can trigger alarms, so we coordinate with you first and follow the steps needed to keep the system covered.
Identifying your device
The type is usually printed on the device or a tag attached to it. Without a label, look at the shape. RPs have a relief port underneath between two checks. Double checks have two check covers and no relief port. PVBs and SVBs have a bonnet on top.
There's no need to figure it out yourself. Send a photo when you book, or let the tester identify it when they arrive.
Older devices and test results
Device type matters less than condition when it comes to passing. A ten-year-old double check that has been rebuilt on schedule can pass easily, while a three-year-old RP on a line full of debris can fail.
That said, older devices do fail more often as rubber ages and parts wear. If yours is old enough that parts are getting hard to find, we'll mention it, so replacement can be planned instead of rushed.
Don't know which one you have?
A quick photo is usually enough for us to tell. Or read our comparison guide.
Questions
Do all types cost the same to test?
Pricing goes by size, not type: $105 for devices under 4 inches and $175 for 4 inches and up.
Do fire line devices need the fire department?
Usually not for the test itself, but we coordinate with you first since closing valves can trigger alarms.
Can you test a device installed underground?
Yes. Let us know when you book if the vault fills with water or dirt so we come ready to clear it.
Is the price different for an RP?
No. We charge by size: $105 under 4 inches, $175 for 4 inches and larger.
Is an RPZ the same as an RP?
Yes. Both names refer to a reduced pressure principle assembly.
Which type is most common on homes?
On sprinkler lines it's usually a PVB or double check. On the main line it's often a double check or RP.
Why Corona customers call us for backflow preventer testing
We're a local company that focuses on backflow prevention. Every test is run by a certified tester with a calibrated gauge, and every report is filed with your water district as part of the job, not as an add-on.
You'll know the price before any work starts. Testing is a flat $105 per device under 4 inches and $175 for 4 inches and up, and repairs, replacements and installs are quoted first. We answer the phone seven days a week from 6am to 12pm, same-week appointments are normal, and emergency calls are taken 24/7. When the job's done, you get a copy of the report by email so you always have proof on hand.
Backflow Preventer Testing in Corona and nearby
Need backflow Preventer Testing outside Corona? We also cover Norco, Eastvale, Home Gardens, Weisel and Arlington. Same-week visits are normal, and booking takes a couple of minutes.