use of unions??

Matt_29

I like to use unions and shut-off valves between all boiler trim (steel or copper piping)..for the easy isolation and disassembly of devices that may fail or need replacement...I was recently advised that this was not a good practice to use alot of unions on hydronic systems...would there be a logical explanation as to why this would not be a good practice?? but to be more specific we are talking about closed hot water boiler systems...and my work never leaks...

Michal

I do the same

WellI do the same on all jobs, to facilitate installation, the only reason I figure not to do it, is that it takes more time and costs a few more doillars. I have never had issues with leaks on them. Unions can leak, but if installed correctly we all know they will not. wonder what the feed back will be from others,

Mark Eatherton1

Unions had their place and time...

back around the turn of the century, coal miners were being abused by "The Company" and the unions were necessary to straighten these situations out...Whats that? OHHHh, THAT union... Sorry, guess I misunderstood. Let me change hats.

There... Unions, while required by code on any appliance that may need changed in the future, are view by the weekend warrior as "Velcro". It invites dangerous and unnecessary HO participation that leads to situations that do not meet the intent of the code, and can cause loss of life. (Water heater on bricks because new water heater was 5" shorter than previous heater, got knocked off bricks by kids rough housing, flooded basement and filled house with natural gas due to broken flex connector)

For THAT reason, I do not use unions unless required to by AHJ, and that has only happened once in my career.

A sawzall is faster than a wrench IMHO...and couplings are cheaper than unions!

ME

Big Ed

Odd

Maybe they were refering to isolation valves . A wrong placed valved could isolate a safey or expandtion tank .

I know of no harm in unions....

REF

Ease of service

I know so-called experts can put a spin on anything; however; unions make life really easy when you need them to. I will give you one real world example. We installed a fitting that had a sand hole in it, but because the union was there it was a quick and easy replacement. Ease of service when you're the one that has to maintain the system is always a good thing.

Respectfully,

Richard Fox

oil-2-4-6-gas

a sawzall may be quicker than a wrench but why would anyone cut a copper pipe to replace something and not put in a union --i've seen many pipes with 2 or more couplings-it just looks like crap --and for black pipe you have no choice --but if it needed to be serviced once it will need to be serviced again put in unions--especially on those feeders --the male-copper unions are nice----i think the even worse is the incorrect placement of unions--there is no way to spin out the piping ---i see this on many feeders and domestic coils--male to a 90 then a union--but the pipes are the same distance from the coil--so why bother

Mark Eatherton1

I was referring

to copper pipes. Guess I should have clarified that.

You must be of East Coast heritage. We only use black iron pipe on gas lines. Everything else is copper. If I have to replace something, I generally cut a 90 in half and resolder back to that point. You can't even tell I was there, and there are NO UNIONS for the DIYer to latch onto.

Not a "spin", just my professional opinion...backed by 32 years worth of Gettin' 'er done!

ME

REF

To Mark

Hey Mark-I was referring to those folks that told the original professional not to use unions on hydronic systems. No offense intended towards yourself. Yep, I'm a yankee. I just agree with the notion that it makes a cleaner job; if they are installed correctly. Even the radiant manifolds we use have unions. They are a lot of ways to skin a cat, and that is one of the great parts of this job. We just removed 5" gravity lines, and if I could thank the deadmen who put the unions in I would. It was so much easier to lower the 5 million pounds of iron to the ground.

PS The quality of all the parts of the job right down to the hangers really amaze all of us. The carpenters were in awe too. 100 years later to the year and I don't know their names, but I still marvel at the craftsmenship. From what I can gather by reading the posts 100 years from now they will marvel at your work and hopefully ours. All the best.

Respectfully,

REF

Weezbo

\"Unions? Break em Straight from the gate...\"

always liked that quote since i was about 5 years old

bob young

onions

unions definitely have their place on threaded screw pipe systems. on copper systems they usually do more harm than good. copper unions are usually flimsy and distort easily. a slip coupling usually works well on a repair if you are a competent mechanic.