MDchanic
New Member
Hello All,
This is my first post on this forum, and may be my last.
I wanted to post some information I learned through trial and error about this particular valve, and this was the only place I could find where it looked appropriate to put it, since I don't have a YouTube channel with a million followers.
The previous owner of my house liked to spend money on plumbing fixtures, and did so with reckless abandon.
All of our fixtures and faucets are Herbeau, with the exception of the shower valve, which is Sigma, which has exactly the same operating components (with the same names and the same posted pdf diagrams) as the Herbeau version.
[image from SigmaFaucetParts.com]
One day, my shower valve began to leak. This didn't bother me, as it was just leaking out of the valve stem and down the drain.
So I left it. For a year or so. Until the basement ceiling began to leak, wrecking some of my wife's paper goods (NOT happy).
At that point I knew I had to act. So I put a pot under it.
Then it started to leak more. So I decided to take things apart (I hate plumbing).
Now, knowing that every faucet in the house says Herbeau on it, I didn't much think about the fact that this one doesn't. It looked just like the units on the Herbeau web page. Herbeau had files with exploded views [see page 2], but no instructions.
So I started removing things.
Pitfalls:
1. Apparently, Herbeau always used a metal temperature dial, but Sigma used to use a plastic one, but doesn't anymore, and they are 100% unavailable.
Without clear instructions, I was unsure of what parts the water would spray out from if I removed them, so I did not want to remove the nut on the valve housing that holds the faceplate on. Instead I pried on the plastic dial, thinking it would snap off. This was a mistake. I bent it up before I realized that it was actually UNDER that nut, which has to come off first.
I did get it all apart, but the plastic dial was a little bent up, so I figured I'd heat it a bit in water to soften it and reshape it.
This was also a mistake, The water had no effect on the plastic until it reached boiling, at which point it turned the plastic into a shriveled warped mess.
Did I mention that new ones are unavailable?
2. The little 90°-valve levers for the two shower outputs look like they have little caps on them that pry off, with screws underneath.
They don't. Those caps are actually little screw heads. Do not pry them. Grab them with Vise-Grips and some sort of cushion and unscrew them.
This is not at all obvious, even from the exploded views.
Fortunately, Sigma has an excellent disassembly guide on their web site (If I'd known this was a Sigma, I would have viewed it and saved a lot of time and destruction).
So,
Sigma wants $220 for these (Sigma Part #18.30.082). Other plumbing supply houses want $90-120 (Jerich #25350).
That's a lot of money for a bad O-ring.
See attached photos:
Good luck (if anyone at all finds this, and finds it helpful)!
- Eric
This is my first post on this forum, and may be my last.
I wanted to post some information I learned through trial and error about this particular valve, and this was the only place I could find where it looked appropriate to put it, since I don't have a YouTube channel with a million followers.
The previous owner of my house liked to spend money on plumbing fixtures, and did so with reckless abandon.
All of our fixtures and faucets are Herbeau, with the exception of the shower valve, which is Sigma, which has exactly the same operating components (with the same names and the same posted pdf diagrams) as the Herbeau version.
[image from SigmaFaucetParts.com]
One day, my shower valve began to leak. This didn't bother me, as it was just leaking out of the valve stem and down the drain.
So I left it. For a year or so. Until the basement ceiling began to leak, wrecking some of my wife's paper goods (NOT happy).
At that point I knew I had to act. So I put a pot under it.
Then it started to leak more. So I decided to take things apart (I hate plumbing).
Now, knowing that every faucet in the house says Herbeau on it, I didn't much think about the fact that this one doesn't. It looked just like the units on the Herbeau web page. Herbeau had files with exploded views [see page 2], but no instructions.
So I started removing things.
Pitfalls:
1. Apparently, Herbeau always used a metal temperature dial, but Sigma used to use a plastic one, but doesn't anymore, and they are 100% unavailable.
Without clear instructions, I was unsure of what parts the water would spray out from if I removed them, so I did not want to remove the nut on the valve housing that holds the faceplate on. Instead I pried on the plastic dial, thinking it would snap off. This was a mistake. I bent it up before I realized that it was actually UNDER that nut, which has to come off first.
I did get it all apart, but the plastic dial was a little bent up, so I figured I'd heat it a bit in water to soften it and reshape it.
This was also a mistake, The water had no effect on the plastic until it reached boiling, at which point it turned the plastic into a shriveled warped mess.
Did I mention that new ones are unavailable?
2. The little 90°-valve levers for the two shower outputs look like they have little caps on them that pry off, with screws underneath.
They don't. Those caps are actually little screw heads. Do not pry them. Grab them with Vise-Grips and some sort of cushion and unscrew them.
This is not at all obvious, even from the exploded views.
Fortunately, Sigma has an excellent disassembly guide on their web site (If I'd known this was a Sigma, I would have viewed it and saved a lot of time and destruction).
So,
- Unscrew cap-like screws holding tiny levers on and remove,
- Unscrew 2mm Allen set screws (2) in knob and remove,
- Slide off trim ring under knob,
- Unscrew larger (1/8") Allen set screw and remove pointer assembly,
- Unscrew large brass nut on valve shaft,
- Gently slide off whatever scale or plastic ring-like piece is on there (note orientation - it has stops for the valve),
- (With plastic stop piece / temperature scale removed, the knob can turn infinitely – DO NOT ALLOW IT TO DO THIS).
- Slice, cut, scrape pry, or whatever is necessary to remove faceplate. It pulls straight off.
- Use a screwdriver or 1/2" socket (new version / old version) to turn stop valves 90° to OFF,
- Vent pressure by turning on shower valves,
- Use a shower valve socket (the biggest one in the set from LoweDepot) to unscrew the housing
- Carefully, but very firmly, pull thermostatic cartridge unit straight out.
- Mark "clock" orientation of cartridge, for reassembly.
Sigma wants $220 for these (Sigma Part #18.30.082). Other plumbing supply houses want $90-120 (Jerich #25350).
That's a lot of money for a bad O-ring.
See attached photos:
- Have a clean work area.
- Remove clip on valve stem,
- Firmly grasp the top and bottom half of the cartridge case, push together, and rotate about 5° CLOCKWISE,
- You are disengaging 4 tiny plastic tabs – That's it, just push together and give a little twist.
- Now, gently pull the two halves apart and remove the pieces.
- WATCH ORIENTATION! Lay everything out just as it comes out, then carefully dry them, then mark them with a felt-tip marker, or whatever, so that you can "clock" them all the right way on reassembly. Does this matter for all parts? I don't know. Why risk it?
- You can clean the areas of the parts that you have made the lines on, one area at a time, so you can accurately re=draw the lines.
- Clean parts. Soak in vinegar overnight, then a quick brush with some ScotchBrite or a fine wire brush.
- BE VERY CAREFUL of the fancy thermostatic unit at the center. It rides in the center of the piston.
- DO NOT Push or Pull on it.
- DO NOT Twist or Turn it.
- Just leave it alone.
- You can push or pull or bang on the piston itself with impunity if you use a couple of sockets the right diameter to get past the thermostatic gizmo.
- Once all is clean, install O-rings as in the pictures.
- Use silicon grease (dielectric grease, available in tiny cheap packets at the auto parts store cash register, if you don't want to buy a tube) on all O-rings, sparingly.
- I bought a bunch of O-rings of various sizes to do this job, then afterwards I wasn't sure exactly which ones I used for which places, hence the question marks in my photos. Get one bigger and one smaller, and you'll be sure to have the right ones.
- Check the clearance of the case O-ring without the internals before trying to reassemble – I used one that looked right, and there was no way that thing would close. I had to use one that seemed just a tiny bit "too small," which worked perfectly.
- The piston O-ring will want to stick in the upper groove of the case. It needs to slide past it (it operates between the upper and lower grooves). Some firm pushing with a socket (NOT on the thermostatic part) will get it past IF it is greased (and not if it is not). It will be a bit of a balancing act to keep the O-ring from popping back up into the groove under spring pressure, before you can remove the socket and attach the other case half, but you can do it.
- On reassembly, you'll have to overcome the force of the spring plus compress the new case O-ring in order to get the tabs to engage – dry hands and firm pressure should do it.
- Once it's together, push it firmly into the housing and set in place by tightening the cover with the shower socket.
- Remaining reassembly is obvious.
- Calibrate temperature at your own risk. When I did, the top setting was barely hot enough to take a comfortable shower (maybe I'm an outlier), so I set it with the needle pointing a bit hotter than 12:00 at my normal temperature).
Good luck (if anyone at all finds this, and finds it helpful)!
- Eric
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