Dope & tape?

Too many leaks back when…. Both gives the best of both worlds.

If some is good, and more is better, then too much must be best.

I've givin' up on the yellow stuff for Megatape on just about everything. Megatape just feels good the way it goes on. Last week, I used Locktite on a Lochinvar indirect tank on the 1-1/2" stainless to copper in and out water supply. I learned my lesson. NO LEAKS. I did use Megatape and the blue dope on the heat exchanger to copper connections which cause me some concern on an earlier job. When everything got fired up, NO LEAKS. I did my happy dance.

Belt and suspenders when you don't want a leak….which is all the time but especially in walls or inaccessible locations. I have done jobs with dope only. Teflon tape makes fitting go on smoother IMHO.

I don't know when Teflon Tape started but I started in 73' and it was in use then.

I can remember a huge job at Amherst College when I started, and we went there for some reason while it was being built.

There was an apprentice sitting in the corner with crates full of black nipples…tons of them. His job was to sit there all day and put Teflon tape on all the nipples…. think I would have quit if I was him.

Tape was available when I started in 1980, but it was thin. Easy to snap off when you’re done winding, but you had to wrap it 10 times to get enough material on the threads. I found a place back east that offered a thicker mil tape and ordered it by the case.

My head hurts :)

What did you do yesterday?

We talked about pipe dope all night.

Maybe we should talk about a Hartford Loop or a Drop Header or something.

Still far, far better than sitting watching reality tv….

At least that's my honest opinion.

Viessmann's Lambda Pro combustion system anyone?

It uses an ionization probe to monitor flue gases, allowing the boiler to auto-calibrate for gas type, quality, and altitude, ensuring high efficiency (up to 98%) and low emissions without manual adjustments.

How come others don't use it?

baxi does, calls it GA "gas adaptive"

you will also see it as a spec option for some commercial units, common engineering term now is "O2 trim" I think the lochinvar name is "hellcat" (an option for Crest boilers), aerco offers "aertrim" for their Benchmark boilers. I'm not positive they all function on the exact same principles as lambda pro, which itself has gone through changes. (just looked up aerco, they are directly monitoring o2 with a sensor, so similar results but a much more expensive way to get there imo)

the current lambda pro+ (plus!) also uses a mass flow air sensor in its calculations in addition to the ionization current.

as to why most don't utilize this? cost primarily. but also they aren't nearly as in control of their supply chain as a company like Viessmann has been. seems silly but the more complicated your burner control, the tighter tolerances you need for components. That adds cost sure, but its also just really hard to do.

I am very much a fan of lambda pro but I am also confident I could steel-man an argument against it if called upon

Yeah, a lot of guys do that tape first, then a light coat of dope over it. It can help lubricate the threads and seal up any tiny gaps the tape might miss.

That said, it’s usually overkill for most jobs. Good quality tape applied properly is enough on its own for most threaded fittings. Just make sure you’re using the right tape (yellow for gas, thicker tape for larger threads, etc.).

If you do use both, go easy on the dope too much can make a mess or even crack fittings if you over-tighten. And always check what the manufacturer recommends, especially for plastic or specialty fittings.

I like blue monster on larger pipe but the typical thin stuff in small stuff like 1/4" and smaller.