HOW TO SECURE & INSULATE PIPES BEHIND WALLS

Hap_Hazzard

A lot of people like the Blue Monster products. Personally, I use Great White, which is a joint compound with PTFE in it, and it never hardens. I tried the Rectorseal with PTFE, but I didn't like the consistency and couldn't get the joints to stop leaking under even the slightest pressure.

I generally tighten fittings about a full turn after they start to get tight. I figure as long as there's some kind of PTFE, be it tape or compound, the joints will swing if they need to.

hankwylerjr

@Hap_Hazzard so if I stay with the monster do I still need the tape as well? Some of the work I've done I used the tape first then the dope never had a leak sometimes I just used the dope on my steam oipes and no leak. I'll try the stuff you use when I'm empty it starts to get clumpy after a bit. I might assemble my joints use a coupler and this way everything is easy. I don't have lots of space for my wrenches but don't want to have any leaks behind my kbee wall leading to my ceiling hence the questions

ethicalpaul

I'm looking forward to the answer to your question--the one about the tightness, not the one about the tape/dope

The tape/dope is a religious war. I use the blue tape only (no dope--this is steam lines I'm talking about, gas is a different story) and have never seen a leak yet. Some use dope on top of tape, OK fine, not sure why. Some use tape on top of dope which just sounds insane to me

As for the tightness, I tighten until they get a little tight (like a quarter beyond hand tight, and then I do about one more 360 turn after that, depending on where I want my final angle. But that is a completely self-taught practice. Again, I want to hear what the pros say. At our pressures, the steam just isn't motivated to squeeze through my joints. If it were 100 psi I'm sure mine would be far from tight enough.

If I had to guess, I bet they'll say something like: tighten it until it won't go any more, then do up to another full 360 after that (I've seen some of their arm muscles in pictures)

Hap_Hazzard

As I understand it, the dope is to make sure it doesn't leak, and the tape is to allow movement and to be kind to your future self if you ever need to take it apart in years to come. Ordinary pipe dope hardens after a few years and it makes it very hard to unscrew the pipes, and it keeps penetrating oils from working because they can't penetrate the threads. By adding thread tape or using a compound that contains PTFE, you allow the joint to move if it needs to.

ethicalpaul

Oh yeah, speaking of joints moving, My old joints do not move. Maybe my new ones do, but those old ones, no way.

hankwylerjr

Lol I'm more confused now then I posted the question. 🤔 Maybe I'll just stay with the tape and a light coat of monster like I have in the past albeit, not on these types of challenging and expensive joints. Hand tight and then a full 360 sounds like a plan. Pray for np leaks above my head right where my bed will be

ethicalpaul

Let some pros answer first before you commit, but yeah even my worst steam joint has never leaked yet (but I know I make better ones now than I used to).

I think the more important thing is to make sure you don't create any valleys where water will sit.

Larry Weingarten

Hello, Once you get it assembled, but before it's hooked up to the system, is there a way to air test it at some pressure higher that it will ever see with steam? That test would let you sleep at night.

Yours, Larry

Hap_Hazzard

@hankwylerjr, sorry if I confused you. I do have a tendency to overexplain things.

I think the dope + tape is fine for the swing joints and every other joint, and I know there are a lot of pros here who use this method. Here are a couple of threads on the subject:

https://forum.heatinghelp.com/discussion/176752/pipe-dope-plus-teflon

https://forum.heatinghelp.com/discussion/173365/plumbers-tape-or-pipe-dope-does-it-matter

These both happen to be in the Radiant Heat forum, but there have been similar discussions in this forum.

Also, if you do a search for "blue monster," you'll find their products very popular here. I might be the only guy who uses Great White, and I'm not even a pro.

hankwylerjr

@Larry Weingarten no, I have no idea how to do that. I'm hoping to get it done in few days I'll keep everyone posted

Jamie Hall

Just tighten them up as you would any threaded joint. To get the alignment you want, it's better to go tighter -- so don't be a gorilla on initially threading them on! Yes, there will be movement, but the angular amount is very small and the joint with tape won't be bothered. Can't really describe how tight is tight enough... there's a feel to it.

hankwylerjr

Fellas, problems here. It took roughly 6 hours to get this far. Through the floors, drilling cutting cleaning up. What is the best way to get these 90s for 2 swing joints? I could not finish tonight because I'm out of energy. Any advice would be great thanks. I am not going to get that required pitch maybe I'm doing something wrong

Hap_Hazzard

I usually work out all the angles before I start tightening anything, then I tighten one joint at a time.

hankwylerjr

I did but then when I put it back together it didn't line up maybe I need another nipple and 90 or something else not sure yet. I'm working behind the knee wall couldn't really assemble it fully then bring it to the 1 1/2 pipe

Hap_Hazzard

If you could line it up loose it should line up when you tighten everything, unless you didn't get them all tight in the right positions. If you tightened them one at a time, at what point did the alignment not work?

hankwylerjr

I wish I knew to be honest. What I need to do is take apart a couple of elbows and start over I didn't tighten them like a guerrilla yet. The problem is that the pipe itself needs to be a little lower but I'll have to make some adjustments to the floor joist maybe notch it out by an inch or so so it doesn't affect the strength or may sister it if I have to cut out more. Looked so easy and pretty before I was laying in cellulose insulation with zero headroom

hankwylerjr

So far... Need adv in how to get these rads aligned with the nipple? Smaller one looks like it lines up better than the larger can't really turn the pipe anymore. Maybe another swing joint near rad? The pipes are pitched as much as possible if you can see the bubble on the level. Thanks

ethicalpaul

I think I’d try a couple 45s and nipples

EBEBRATT-Ed

Using the right size pipe wrench for the pipe and you will automatically know when it's tight. 1"=14" wrench, 1 1/4"=18" wrench.

Sometimes you have to use a wrench larger that you would normally have to use if in an awkward position position. Try tightening a couple of fittings when you are in a good spot just for practice.

Teflon tape and most any pipe dope is fine. It's like asking what kind of beer you like everyone has a favorite

hankwylerjr

@ethicalpaul I tried a couple 45s nipples still didnt get my pipes to line up properly the nipple off the riser is crooked due to the angle . Did I confuse you with last post? Sorry I rambled on because there are a few things I talked about in one post.
The other thing I talked about was the pitch on both nipples going to riser. Is this pitch acceptable? Thank you

hankwylerjr

@EBEBRATT-Ed sorry i confused anyone. Got the correct tightness down pretty good. I am using 2 24 inch and have a 3 foot helper just in case. The issue is lining up the nipples coming off the risers. I cant get them so Ive used 2 90s and nipples near the riser but maybe need more near the rad to make the connection. Im using blue monster tape and dope on everything

ethicalpaul

The pitch looks plenty good. It’s hard to tell without being there, but some combination of fittings should get you there. If it can’t you’ll have to work backwards to redo some of it.

I will say in my limited experience with pipefitting, that last few inches is the hardest!

hankwylerjr

@ethicalpaul I can't really rework the pipe there is nothing further at the connector to the riser I can't do at the end in my opinion. I've dry fitted various combos with 90s that's the best with this angle I'm going to get I'll keep you posted though

Hap_Hazzard

If you have room to add a union, that might help.

hankwylerjr

@Hap_Hazzard I do but because of the pitch and whatnot, I am finding it hard to connect to rad. I'm even wondering about a 22 1/2 or I think they make an 11 1/2 angles but way too expensive. I don't think that by adding another 90 at the riser connection will help because of the crazy angle. Maybe some 45 degree angles with nipples or combo of 90 and 45s? Very frustrating and I need heat very soon. I guess I could just connect it with rad at an angle but look like crap unless I can build or buy rad cover box like piece to hide it

JUGHNE

IIWM, I would start at the rad valve and dry fit back towards the riser.
Put the rad where you want it, have a pipe go into the wall connected to the valve, it would have to slope down to 1 90 to head towards the riser, then at the riser use 2 90's to get the slope on the first horizontal pipe.
I use short lengths with couplings for dry fitting.
Get things lined up and measure for pipe lengths.

If you lack enough slope from the rad you might have to prop the rad up with 2 X 4 blocks with an added shim on the vent end.

May or not work for your situation