View Full Version : 1/2" IPS -what connector?

05-24-2011, 09:39 PM
Hello, I have a Danze D113000BT shower mixing valve. It has male ports described as "1/2 inch IPS threaded coupling connections". I bought female (I think I got that bit right!) 1/2" PEX by 1/2" FPT Propex adapaters to hook them up. Checking on the web, I came across the fact that IPS can mean "Iron Pipe Straight", and that connections with this feature should have a gasket (as in hose, or washing machine connections?). The instructions do tell me to use tape, so does that mean the threads are in fact tapered and IPS just means "Iron Pipe Size", and my FPT fittings are ok? It's all very confusing. Thanks for any help.

05-25-2011, 05:40 AM
IPS, the way that faucet, and in most cases, uses it means Iron Pipe SIZE. I do not think I have ever seen it refer to "iron pipe straight". Even when the thread is "straight" such as faucet shanks, they still refer to it as iron pipe size. It is confusing because you are a DIYer rather than a plumber.

05-25-2011, 06:48 AM
IPS means 'iron pipe size' and unless otherwise stated, would usually imply tapered. The term NPS is use for example on a faucet connector, 'national pipe thread straight' as opposed to NPT, tapered. Confused yet?

05-25-2011, 10:21 AM
Thank you both. I think I can move on and use my fittings. There's a lot to this plumbing business.

05-25-2011, 01:18 PM
While pex is fine on the inlet, just make sure you use copper or brass and not pex for the outlets, especially if you have a tub spout with diverter, or you'll end up with problems.

It would be obvious when you tried to thread the adapter into the valve if it was straight or tapered. If straight, it would likely bottom out and never get tight except for hitting bottom. A tapered fitting would tighten down as you went before it hit bottom. Also, if it was a straight thread, it would often come with a gasket or washer.

05-25-2011, 02:49 PM
The mixing valve has 4 male ports. I was going to use Pex (propex expander method) on all four ports. (Two supply ports, one shower head outlet and one outlet to supply a hand-held gismo (via diverter)). What would be the problem with Pex on the outlets?

The attached pic isn't mine, but I assuem this is the sort of thing you're talking about leading to problems?

I understand your comment on the tapered thread.

05-25-2011, 02:54 PM
PEX is an undersized pipe. If you read the instructions on the valve, it will warn you not to use PEX for the tub spout.

Here is what happens with PEX; when you run the tub, since the piping is undersized, some of the water will divert up to the shower head as you are filling the tub.

That's why they have the warning about PEX in the instructions.

05-25-2011, 02:58 PM
The problem only occurs when you are using a tub spout with a diverter, as PEX has a smaller I.D. than copper. If you are doing a shower valve only, there should not be an issue. Most plumbers prefer to use all copper on a shower or tub valve as it is more easily secured inside the wall than PEX which helps to ensure the valve or shower arm will not become loose in the wall.

05-25-2011, 04:02 PM
Thanks again. Yes the instructions do indeed say to use only copper or iron pipe to the tub spout.
I understand the logic there, but I have a hand held thing with a diverter (no tub) coming off the bottom port. So does the argument of not using pex on the bottom outlet of the valve still apply? I'm thinkint the diverter will just shunt water one way or the other and that I fall under cacher_chick's scenario. (I'm leaning to pex because it gives me flexibility in the final position fo the valve with respect to where I think the finsihed wall will be). Thanks for all the help.

05-25-2011, 04:18 PM
It depends, some diverters switch the water by actually shutting off ports and reconnecting others. Some, just cover the port you don't want, and the others are still open, relying on gravity or volume to get it where it is supposed to, and stopping it from being able to flow where you don't want it. If there is more restriction than designed, water could go places you don't want it to.

05-25-2011, 04:45 PM
OK thanks. Since I don't know how this diverter works, it looks like I should play it safe and use copper for the lower port. Thanks all.

05-26-2011, 07:14 AM
Your installation SHOULD have problems no matter what kind of pipe you use. ANYTHING attached to the bottom opening, other than a diverter spout, WILL cause water to flow up to the shower head everytime the valve is turned on. The only thing the diverter, and I am not sure what kind you would have, will do is stop the flow to the handheld. If you had used copper tubing instead of PEX, you could have eliminated the adapters and connected the tubing directly into the valve's ports.

05-26-2011, 10:55 AM
Just to clarify, I haven't done anything yet (the photo was not my set-up-I added it to address jadnashua's input; it perhaps confused things).
Anyway, I'm now a little confused. Are you saying that the lower port on my mixing valve can only ever be used for a tub spout (with copper)? Is there a configuration that will work for the hand-held?

If the diverter just shuts off the hand held, and the pipe to the hand held is bigger than the one to the shower head, then wouldn't water go to the handheld, given it's always lower? Just trying to understand this and not get soaked every time I clean the shower pan. Thanks.

05-26-2011, 01:16 PM
Exactly what diverter valve are you planning on using? Some work by the differential sized openings, and when you close one, it forces it out the other. But, when you don't have it closed, both are open...it's just that one has less restrictions, and so the water flows out there. If you add restrictions, then it can force water out both outlets. Some diverter valves do literally close off ports as they open up others. To see if it'll work, you need to know exactly what you have.

Many valves are made so that you can use them as a female fitting for the specified pipe and not have a threaded connection there at all. Or, you can thread on a female adapter and make your connection to whatever. The fewer threaded connections you have, the better off you are, in my view, especially when there's more than one on the valve. Move it, and one tightens and the other loosens...not the best situation. Solder them in, and they're solid forever.

05-26-2011, 04:22 PM
Since the instructions warn me that I should use copper on the lower port if I was to use the lower port for a tub spout, I think the diverter must work in the 1st way you described; that is, in the "tub spout" position the shower head and lower port are both open and in the "shower head" position, the lower port is shut off and water's forced up to the shower head. It may end up being a trial and error thing for me as I plan on using the shower w/out th walls finished for a few days (plastic sheeting) and I can see if it works.

(I understand your point on the threaded connections and there is indeed a soldering option on these ports but the instructions warn me I may not get the whole unit hot enough (too much of a heat sink?) to solder, even with MAPP gas. Given that and my limited soldering skill, I'm leery about doing it that way). Thanks for your responses.

05-26-2011, 05:32 PM
If you take the cartridge out, what's left is all brass, and the heat shouldn't bother it...but, lots of people screw in a fitting and don't have problems. Hassle is, if it does leak after it's all together, it gets really messy. Maybe not as bad with pex, since it may slide and you could give the fitting another 1/4-turn or so.