<--- Begin Local Business Schema!---> <---End Local Business Schema--->
(415) 457-1145 Request Service

Backflow Testing and Replacement

Backflow Testing and Replacement

What is Backflow?

–Back-siphonage occurs when a sudden drop in pressure causes suction of used or contaminated water back into the water supply. For example, let’s say a homeowner uses pesticides in their lawn, then waters the yard and water pools around a sprinkler head. Then the fire hydrant down the street is used, causing a sudden drop in water pressure. The water around the sprinkler head can be sucked back into the potable (public) water supply, contaminating the community’s drinking water supply. Back-pressure occurs when water is forced to flow in the opposite direction due to pressure downstream increasing the system pressure. Gotelli Plumbing offers backflow testing to identify if your plumbing systems are dealing with backflow problems. If we identify a problem, we can also provide expert backflow repair.

Backflow Preventer Installation in San Rafael

A backflow preventer can be installed on your home’s pipes. It prevents water from being siphoned or forced back into the potable water supply. Backflow preventers are mechanical in nature and have many moving parts which have a higher potential to malfunction than non-moving pieces – so you should have your backflow preventer tested annually to ensure that it is functioning properly. If your backflow preventer is not functioning properly, it must be repaired.

3 Types of Backflow Preventers


There are three types of backflow preventers – pressure vacuum breaker assemblies, reduced pressure zone assemblies and double check valve assemblies.

  • Pressure Vacuum Breaker Assemblies
    The most commonly used assembly is the pressure vacuum breaker, which has the simplest design – making them easy to install, maintain and repair. This assembly prevents back-siphonage only, not back-pressure.
  • Reduced Pressure Zone Assemblies (RPZ)
    RPZs are the most complex and expensive backflow preventers but, when functioning properly, are most reliable. This type of backflow preventer can be installed either above or below ground, although above ground is preferred, and protects against both back-siphonage and back-pressure.
  • Double Check Valve Assemblies (DCA)
    Double check valve assemblies are the best option for underground or indoor installations. DCAs are the most commonly approved underground backflow preventer, although they can also be installed above ground, depending on the installation code for your area.

If you’re unsure if you have or need a backflow preventer, need your existing backflow preventer tested or need it repaired or replaced, give us a call and we can help!

Why Choose Gotelli Plumbing?

5-star customer service
Customer Focused
Our goal is to give every customer the best plumbing service available. Our technicians are professional and well-trained to make sure we achieve that goal.
family owned business
Family-Owned and Operated
We're a family-run business living and working in Marin County, so treating our neighbors like family is the center of our values.
sewer services
Reliable Service
Our technicians are background checked and trained in the latest plumbing advancements to ensure you get the service your home or business deserves.

What Our Customers Say

Very Professional

Very professional, very accommodating and very successful unclogging solution to our plumbing emergency. Many thanks!

Michael M.

Fast and Efficient

It was great working with Sam S! He’s fast and efficient. He found the problem in a matter a few short minutes. Then he had the part delivered to our home. Thank you!!!

Stephen S.

Courteous and Thorough

Cory was very professional, courteous, thorough, and fixed the problem. Also, the women I spoke with on Friday morning was also very courteous and accommodating . 5 stars for sure!!!

Chris H.

Pleasant Attitude

Cory came out to inspect a questionable smell from under my house and quickly was able to identify the source – a decomposing rat that my pest control guy was on able to locate after three previous visits! Thank you Cory for your fast and efficient service and a pleasant attitude!

Rebecca C.

Quick Response Time

The response from Gotelli Plumbing was excellent. The next time Tom arrived right on time and the quality of his work was outstanding. When he finished he walked me through everything he had done and I could not have been more pleased with the results. I’m so thankful to have such professionals available when need and on such short notice.

Raymond R.

Excellent Service

Tom provided excellent service. He is obviously experienced- and quickly solved the problem. Our gas had to be shut off, so we were without our stove to cook, furnace to heat and hot water. Our home is happy again!

Keith B.

Superb Service

Tom of Gotelli Plumbing provided superb service for us in replacing a very balky tub spout, and worn out toilet parts. Not only was he extremely professional and thorough but he was able to answer all my questions concerning the service. I would give 6 stars if I could.

Edward D.

Always on Time

Tom has worked on numerous plumbing issues in our home over the years. He’s always on time, polite, hard working and an excellent plumber overall. I strongly recommend Tom R. for any plumbing jobs you need! We’ll continue to use Tom for all our future plumbing problems. Thanks!

Rachel C.

Fantastic Service

Fantastic service from Steve, who came to our home on time, surveyed the issue, and came back to fix the problem – all with a smile.

Bill D.

Great Experience

I had a great experience with Gotelli Plumbing when we needed a leak in a pipe fixed. Tom was professional and friendly. He also got the job done faster than original estimated, so the work was less expensive than I anticipated. I will use Gotelli Plumbing again in the future.

Kendall F.

Affordable Pricing

Water heater died just in time for Thanksgiving company to arrive. Gotelli sent Joey out first thing this morning. Not only was Joey a super nice guy, he fixed our heater quickly and for $450 less than a competitors bid. Will be going to these guys for all of our plumbing needs in the future!

Becky R.

Fabulous Attention to Detail

Fabulous attention to detail…every decision is made with first rate materials. No cutting corners…great customer service!!

Sherri C.