Hi this is Jeff, today i'd like to talk to you about faucet stems. The stem in anybody's faucet is the mechanism that actually shuts the water on and off and such out of a faucet. So what we at Fisher do is we have check stems, 2 part swivel stems. The 2 part swivel stem is used in faucets where there is just two valves. Picture the hot water side and the cold water side of a faucet and that application we would use the 2 part swivel stem. Okay, check stems consist of three basic parts: the disc retainer and seat washer, a stainless steel spring, and the stem body. The spring lives inside the body and the disc retainer fits inside and that' has become the spring-loaded check stem. Spring loaded check stems are designed to prevent cross flow. So let's take a look at this faucet cross section and look at what cross flow is. Cross flow is when you have a differential in water pressure between the hot and the col. For example you might have 60 pounds of water pressure on the hot and maybe 40 pounds of water pressure on the cold. That'd be 20 PSI differential between the two. IF both these valves were completely open, you can see where the hot water at 60 PSI, 20 pound difference is going to flow right into the cold side, and now you're putting hot water into the cold side which means you're putting hot water into an ice machine or flushing toilets with hot water, not a good thing. So what we do is we put in spring loaded check valves to prevent that. So, whenever we have a faucet fixture with one, two, and three maybe a spray valve out of here, three valves, as soon as that third valve is closed, all this water becomes static and these springs come down and shut off the water supply to the faucet, preventing cross flow. Okay, so now let's take a look at the Fisher swivel stem. We use a two part swivel stem, and what we mean by that is the black seat washer is attached to a swivel on the end of the stem. So as the stem screws down into the faucet body and it makes contact with our stainless steel seat, as soon as it makes contact it becomes more of a plunging action. This is why the Fisher 2 part swivel stem means lower maintenance. One of the most important things in anybody's faucet is going to be the seat. The seat is actually the part where the rubber seat washer seats onto the seat to shut the water off. Everybody else uses brass seats. Brass is a very soft material, and as water flows across that seat, it erodes the seat, and then no matter how many times you replace the seat washer, it still leaks. Fisher uses stainless steel seats in all of its products. Stainless steel seats guaranteed for life. Well it seems that Fisher's stem story is complete. A 2 part swivel stem means lower maintenance and stainless steel seats that are guaranteed for life. That's Fisher, thanks for watching.
Learn all about the ins and outs of Fisher's check stems and 2 part swivel stems by watching this video. With great features, including stainless steel seats with a lifetime guarantee, it's no wonder you'll choose Fisher for all your faucet needs!