There are many different brands of faucets on the market.
Some of the most common faucet brands are:
Some faucets are easily identified and sometimes it is more difficult. The best way to identify the faucet you have is by the manufacturer’s name found on the front of the base. The base is the part that the stems and spout attach to. If the brand name has been worn off from age you may find the name on the end of the spout. If you are still not able to identify the type of faucet, then we move on to identifying portions of the stem faucet. The shape of the spout would be another factor.
Most manufacturers have different shaped spouts. This includes the angle at which they are bent to the curvature of the bends. Another identifying factor is how it attaches to the body. They all have a nut that either screws into the body (male threads) or screws over the outside of the body (female thread). Most have the female threaded nut, so the last identifying possibility is whether there are o-rings on the part that inserts into the body. Some may have a double or a single o-ring (rubber). There are others that have a brass sealing ring.
Sometimes you still may not be able to identify the faucet correctly. The last means of identification are the stem assemblies. Of course, they vary by manufacturer, and some may have different stem assemblies depending on whether or not they go into a standard duty or heavy duty faucet. They may also vary if it is a wall mount or deck mount faucet.
There are three manufacturers (CHG, T&S, and Krowne) that use what is called a barrel type stem assembly. The barrel inserts into the body of the faucet and the stems screw into the barrel. They do differ and are not interchangeable. The T&S and Krowne can be confused with one another because of the bonnet assembly, although the handles are very different and the name may be embossed into the stem. Encore/CHG is fairly easy to identify by the black plastic cap that covers the packing nut that screws into the bonnet nut.
Identifying other stem assemblies may be a little more difficult. You would need to remove the stem for proper identification. Look at the bonnet nut to see if it is a female or male thread. Check to see if it has o-rings on it (single or double), or no o-rings. Also check the spline on the stem, which is at the top of the stem where the handle attaches. It can help sometimes. For example, a Chicago stem has no spline and it is square. A Perlick stem has no spline. These are not interchangeable so be sure you are getting the right one.
If all else fails compare your stem to pictures of stems and assemblies online. If you are unable to match up your stem, it may be a discontinued model or it may be a residential version. If this is the case you may have to replace the entire faucet.
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