Braided Supply hose interface - NPSM

[ValenteBandR]

I have a need to purchase longer supply hoses for a roman tub but am trying to determine definitively if it's comp, IP or other. Manufacturer and distributor are not able to ID, but I did receive a pic calling it out as 3/4-14NPSM-2B (and yes, it's 3/4 to 3/4). It would appear to me as comp (especially as the original has a cone washer), but one supplier said pipe. Anyone familiar with this call out?

 

[Reach4]

I interpret the 4 connections you pointed to in red as being part of the assembly delivering water from valves to spigot, rather than supply lines. I think #16 would have been the included connection lines.

 

[Sponsor]

 

[ValenteBandR]

I interpret the 4 connections you pointed to in red as being part of the assembly delivering water from valves to spigot, rather than supply lines. I think #16 would have been the included connection lines.

the 4 points in red are the connection between the cartridges / handles and the spout. 12" lines were supplied but I need appr. 16-24 depending on routing and spout intake orientation. So yes, I have 2 3/4x12" braided supply, which I took to two suppliers (including Fergusons who is the parent company of Signature Hardware) neither of which could definitively tell me if it's one or the other (one said I should be able to use IP hoses but I'd not 'guess' as a 2nd store water leak above a kitchen could cost a lot to repair. If either had comp 3/4x3/4 I would have just bought them but no one locally stocks such an item. Yes, I mocked up one connection with a 3/4x3/4 IP end (water heater hose) with no observable leaks but I'm feeling hugely confident that that's going to prove out in time. I did consider stepping down to 1/2 (since that's what supplies the tub anways) so that I can use more common 1/2 comp lines....

 

[ValenteBandR]

I did finally find this that explains NPS (M presumably male), though I myself have not heard it referrd to as this. It's definitely not IP (NPT) though... I am under the impression "compression" is attained though a combination of 'seat' on the nipple and the tapered bushing/ washer. Any clarification appreciated.

 

[Reach4]

The NPS gets sealed with a gasket off the end of the thread.

NPT and NPS are not totally incompatible. On the top of a water heater, for example, some connections use a gasket and straight threads, but you can also put a tapered FNPT fitting alternatively, on that very same nipple.

If the female piece has a gasket, do not use PTFE tape. If not, use PTFE tape and/or pipe compound (pipe dope).

 

[Terry]

MIRED3RT BN/CP

 

[ValenteBandR]

What brand and model number is the tub faucet?

Hi Terry, nothing I would consider specific but here's what they publish:
They have it as a max 8"o.c. but in this instance we had to offset the valves/ handles and the spout is appr. 12" away. The spout has a inlets @ 180degrees opposite so routing requires a little more mucking around...

EDENTON 3-HOLE ROMAN TUB FAUCET​

SKU : 948679
https://www.signaturehardware.com/e...fcVT9xd1wjTZQTwSE8AL4Val0kNmLnBoCFmoQAvD_BwE#

Edenton 3-Hole Roman Tub Faucet - With Rough-In Valve - Brushed Nickel | Signature Hardware

Shop Edenton 3-Hole Roman Tub Faucet - With Rough-In Valve - Brushed Nickel. Enjoy free shipping on orders over $99.

www.signaturehardware.com

 

[John Gayewski]

I'm about sure npt and nps have the same threads per inch and a braided supply line would fit on either one.

 

[Jeff H Young]

national pipe straight mechanical thread . i think a water heater flex fits that

 

[Terry]

I think I would be inclined to see if 3/4" FIP would work for those fittings and then use PEX. I'm not a fan of braided connectors that aren't where you can replace them when they fail.

 

[Terry]

Or maybe stainless steel water heater flex. They are much better than braided supplies.

 

[Jeff H Young]

If there is no access than forget about any type of water heater flex, That I know of! Tub valve manufacture might have something approved. Terrys Idea of PEX is good be sure your threaded connection at valve fits the requirement since its not a tapered thread it will have some sort of hose washer, I'm not 100 percent sure of the legal aspect, but would be sure of the proper joint before burying it

 

[ValenteBandR]

If there is no access than forget about any type of water heater flex, That I know of! Tub valve manufacture might have something approved. Terrys Idea of PEX is good be sure your threaded connection at valve fits the requirement since its not a tapered thread it will have some sort of hose washer, I'm not 100 percent sure of the legal aspect, but would be sure of the proper joint before burying it

Thanks for the tip, no braided (I was replacing in kind with what was provided). Had thought about corrugated copper but space limitations make tight bends a little tricky. I can go pex; I use the crimp fittings but haven't seen the pex fittings that are pictured if you wouldn't mind sharing what they are. Also looks like that's hard piped with corrugated copper. Little more room under there than what I'm dealing with; okay a lot more room And yes, a pilot FIP supply connection hasn't shown leaks, yet, but I don't want to risk it. Will go to Pex and FIP.

 

[ValenteBandR]

Thanks for the tip, no braided (I was replacing in kind with what was provided). Had thought about corrugated copper but space limitations make tight bends a little tricky. I can go pex; I use the crimp fittings but haven't seen the pex fittings that are pictured if you wouldn't mind sharing what they are. Also looks like that's hard piped with corrugated copper. Little more room under there than what I'm dealing with; okay a lot more room And yes, a pilot FIP supply connection hasn't shown leaks, yet, but I don't want to risk it. Will go to Pex and FIP.

(not that I believe _everything_ I read on the internet )

Q: Are NPT and NPS threads compatible?
A: NPT/NPS and BSP threads are not compatible due to the differences in their thread forms, and not just the fact that most sizes have a different pitch. https://www.valvesonline.com.au/references/threads/

"NPT (National Pipe Thread) and NPS (National Pipe Straight) have the same thread angle, shape, and pitch (threads per inch). However, NPT threads are tapered and NPS threads are straight (parallel). Both threads have a 60° included angle and have flat peaks and valleys"

 

[Jeff H Young]

A copper corrugated water flex will fit and if you have an access to it I'd use it. The pictured installation with PEX is not the same as you have and that install is no question legal to me.
Are you planning PEX with a FIP to go on a 3/4 npsm thread might not be good idea.

 

[ValenteBandR]

A copper corrugated water flex will fit and if you have an access to it I'd use it. The pictured installation with PEX is not the same as you have and that install is no question legal to me.
Are you planning PEX with a FIP to go on a 3/4 npsm thread might not be good idea.

The way I was reading it was FIP is as likely to work as any other available (since I can't find 3/4 comp or NPS) so the only change I would make is instead using braided is to use a PEX with a FIP termination or as you suggested corrugated copper. Any last words? Tomorrow is go day... And thanks to all.

 

[John Gayewski]

The way I was reading it was FIP is as likely to work as any other available (since I can't find 3/4 comp or NPS) so the only change I would make is instead using braided is to use a PEX with a FIP termination or as you suggested corrugated copper. Any last words? Tomorrow is go day... And thanks to all.

There is an adapter. If you search this site it's come up before.

 

[John Gayewski]

https://www.amazon.com/Fitting-Converter-Adapter-Connector-Extension/dp/B08JCLHLDK/ref=sr_1_5?keywords=nps+adapter&qid=1648200049&sr=8-5

 

[ValenteBandR]

https://www.amazon.com/Fitting-Converter-Adapter-Connector-Extension/dp/B08JCLHLDK/ref=sr_1_5?keywords=nps+adapter&qid=1648200049&sr=8-5

Thank you for the link! That's exactly what I was looking for but couldn't find (Finding things online is amazing isn't it? )

 

[Reach4]

Thank you for the link! That's exactly what I was looking for but couldn't find (Finding things online is amazing isn't it? )

I don't think that is an NPS to NPT adapter. It adapts to a G thread, which is a European thing.