Simple Plumbing Question - Hopefully

chome360

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Hi All,

I think I have a simple plumbing question here, but haven't found anything online and I've searched a lot!

First time doing my own plumbing. Laying everything out and I found a snag. I thought glide glue my pipe into my bulkhead and do a union on the other end of the pipe. Then slide the whole thing through my drain hole on my tank. I checked and that side of The union fits through the hole in my glass just barely. But that doesn't work because the nut can't slip over the side of that the half of the union.

What's the most common practice here? I imagine I could flip my bulkheads upside down, keeping the rubber washer on the water side. That's how Innovative Marine does it. Everything I've bought so far is slip to slip, maybe I need to be slip to thread? Or I put everything in as originally planned but then I can't remove it, I'm going to have to cut plumbing in order get anything disconnected down the road.

I know I'm missing something obvious here, any help pointing me in the right direction?

Haven't bought the pipe yet, but attached is the picture of the bulkhead and true Union I'm using. Hayward and Spears.

1000043644.jpg




1000043645.jpg
 

UncommonSense

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Hi All,

I think I have a simple plumbing question here, but haven't found anything online and I've searched a lot!

First time doing my own plumbing. Laying everything out and I found a snag. I thought glide glue my pipe into my bulkhead and do a union on the other end of the pipe. Then slide the whole thing through my drain hole on my tank. I checked and that side of The union fits through the hole in my glass just barely. But that doesn't work because the nut can't slip over the side of that the half of the union.

What's the most common practice here? I imagine I could flip my bulkheads upside down, keeping the rubber washer on the water side. That's how Innovative Marine does it. Everything I've bought so far is slip to slip, maybe I need to be slip to thread? Or I put everything in as originally planned but then I can't remove it, I'm going to have to cut plumbing in order get anything disconnected down the road.

I know I'm missing something obvious here, any help pointing me in the right direction?

Haven't bought the pipe yet, but attached is the picture of the bulkhead and true Union I'm using. Hayward and Spears.

1000043644.jpg




1000043645.jpg
You aren’t missing anything obvious! This is quite a common trap!

Bulkhead fittings with a slip socket on the locking nut side are typically a one-time use item! (unless you leave a long enough pipe stub glued into the bulkhead before your next fitting to cut your plumbing there then re-glue to a new fitting using your remaining pipe stub)…

It’s a very common problem, honestly…

Solutions:

— use a straight Slip to NPT adapter immediately after the bulkhead, allowing you to unscrew the downstream plumbing from the bulkhead… this means you loose several inches to adapter fittings, though…

— return those Hayward bulkhead fittings (excellent choice, by the way!) in favor of the model which is slip on the flange side, and NPT on the nut side! (Or just NPT/NPT)


I usually like to do Slip X thread bulkheads (slip on flange side) for holes in the bottom pane of a tank, allowing me to stick standpipes straight into them! — I then use a threaded nipple to a NPT union (or ideally, NPT on one side of union, slip on the other side; this combines your union and an adapter fitting!)

I use a union immediately after each bulkhead despite the NPT bulkhead choice, because it allows me to quickly remove plumbing for access/service without risking breaking the tank’s “seals”! — the union also tends to want to rotate at the friction coupling before the bulkhead fitting above it tries to unscrew when plumbing is jostled!
 
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chome360

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You aren’t missing anything obvious! This is quite a common trap!

Bulkhead fittings with a slip socket on the locking nut side are typically a one-time use item! (unless you leave a long enough pipe stub glued into the bulkhead before your next fitting to cut your plumbing there then re-glue to a new fitting using your remaining pipe stub)…

It’s a very common problem, honestly…

Solutions:

— use a straight Slip to NPT adapter immediately after the bulkhead, allowing you to unscrew the downstream plumbing from the bulkhead… this means you loose several inches to adapter fittings, though…

— return those Hayward bulkhead fittings (excellent choice, by the way!) in favor of the model which is slip on the flange side, and NPT on the nut side! (Or just NPT/NPT)


I usually like to do Slip X thread bulkheads (slip on flange side) for holes in the bottom pane of a tank, allowing me to stick standpipes straight into them! — I then use a threaded nipple to a NPT union (or ideally, NPT on one side of union, slip on the other side; this combines your union and an adapter fitting!)

I use a union immediately after each bulkhead despite the NPT bulkhead choice, because it allows me to quickly remove plumbing for access/service without risking breaking the tank’s “seals”! — the union also tends to want to rotate at the friction coupling before the bulkhead fitting above it tries to unscrew when plumbing is jostled!
Thank you! I'm definitely wanting to return and get the right parts to really do this text book. Here's a diagram of my current planned setup. I've bought everything you see except for all the straight pipe sections and the 2 ball valves (didn't draw the ball valves).

Can you tell me which parts in that diagram should be NTP? I'm having trouble picturing it.

Plumbing.png
 

UncommonSense

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Thank you! I'm definitely wanting to return and get the right parts to really do this text book. Here's a diagram of my current planned setup. I've bought everything you see except for all the straight pipe sections and the 2 ball valves (didn't draw the ball valves).

Can you tell me which parts in that diagram should be NTP? I'm having trouble picturing it.

Plumbing.png
If it was my plumbing project, I would do it like this:

IMG_0271.jpeg


Blue circles are segments that would be NPT, red lines are changes from 90 elbows to 45 elbows:

(All pipe stubs inside blue circles would instead be threaded nipples, or would just be omitted in favor of fittings with male NPT on one side!)

— the threads/lock nut side of each drain bulkhead fitting (so they can be easily removed for preventative gasket replacement in a half-decade or so)

— one half of each display tank side drain union would be NPT (these then serve as both unions and NPT to slip adapters in one fitting!)

— the gate valve, with an NPT to slip 45 degree adapter elbow coming out of it, maybe “spigot” (aka “street”) style with male threads… (alternatively, a 90 adapter elbow does work; the drains just do better without any horizontal plumbing)

— the two return plumbing tank side bulkheads are NPT on BOTH sides of the fitting, use a NPT to slip 90 adapter elbow immediately after each bulkhead… possibly street style with male threads if it doesn’t bring the subsequent plumb too close to the tank wall for your downstream valves/unions to fit! (NPT on both sides of return bulkhead fittings allows you to remove and change the nozzles/etc inside the tank!)

— the three red lines just indicate how you can make the three drains connect to the sump while using 45 degree elbows, vs. 90 degree elbows; ensuring your gravity drains constantly flow downhill!

— the bulkheads and unions down at the sump being all slip/glued is typically fine, as they can just be decoupled and moved with the sump! — these parts rarely need to be serviced, if ever!


Example of Hayward slip to NPT bulkhead fitting:
image.jpg
image.jpg
 
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chome360

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If it was my plumbing project, I would do it like this:

IMG_0271.jpeg


Blue circles are segments that would be NPT, red lines are changes from 90 elbows to 45 elbows:

(All pipe stubs inside blue circles would instead be threaded nipples, or would just be omitted in favor of fittings with male NPT on one side!)

— the threads/lock nut side of each drain bulkhead fitting (so they can be easily removed for preventative gasket replacement in a half-decade or so)

— one half of each display tank side drain union would be NPT (these then serve as both unions and NPT to slip adapters in one fitting!)

— the gate valve, with an NPT to slip 45 degree adapter elbow coming out of it, maybe “spigot” (aka “street”) style with male threads… (alternatively, a 90 adapter elbow does work; the drains just do better without any horizontal plumbing)

— the two return plumbing tank side bulkheads are NPT on BOTH sides of the fitting, use a NPT to slip 90 adapter elbow immediately after each bulkhead… possibly street style with male threads if it doesn’t bring the subsequent plumb too close to the tank wall for your downstream valves/unions to fit! (NPT on both sides of return bulkhead fittings allows you to remove and change the nozzles/etc inside the tank!)

— the three red lines just indicate how you can make the three drains connect to the sump while using 45 degree elbows, vs. 90 degree elbows; ensuring your gravity drains constantly flow downhill!

— the bulkheads and unions down at the sump being all slip/glued is typically fine, as they can just be decoupled and moved with the sump! — these parts rarely need to be serviced, if ever!


Example of Hayward slip to NPT bulkhead fitting:
image.jpg
image.jpg
Awesome info! Thanks for pulling this all together for me.

One question - could I get away with just adding male pipe adapters to the ends of the pipe right before going into the bulkheads for the drains and returns? And swapping out those bulkheads for trheaded instead of slip? In the updated pic below I added male threaded pipe adapters. The parts marked in red are what I would change to threaded. Does that work?

for the pipe adapters, something like this https://www.bulkreefsupply.com/schedule-80-male-pipe-adapter.html

Looking at your picture, you're also going threaded all the way to the gate valve, as well as one side of the unions.

For the 90 elbows on the drain, I agree. I actually am uing 2 "sweeping" 90's, not the ones I drew.

Plumbing_updated.png
 

UncommonSense

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could I get away with just adding male pipe adapters to the ends of the pipe right before going into the bulkheads for the drains and returns? And swapping out those bulkheads for trheaded instead of slip?
Yup! This works! It’s just a bit of extra length of fittings before you can make the plumbing start going where you want it!
 

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