Hydronic system cast iron replumb

[sjepps]

I am currently at a loss on how to proceed with replumbing my 1921 orginally gravity fed hydronic system.

I am trying to convert the house from a single zone to a four zone system. I tried to include local contractors but not a single one would do a load calculation or offer anything outside of a generic solution of replacing my boiler with the same thermals. 0/3 even knew what a buffer tank was (I'm planning on adding an outdoor reset and radiant floor system). I was very dissapointed with the local "experts." I designed and modeled the system myself and feel comfortable with what I have planned (1.5" copper headers to 50gal buffer tank [oversized I know] to 6 [eventual] pump fed zones).

Most of the house is 6-inch cast. I don't want to remove the cast but I do need to replumb it to separate it out to different zones. I'm having trouble removing the male connections. I've tried torching the female ends and using pipe break to no avail. I am considering using a larger propare torch or using a chain pipe breaker and then grinding out the male end to allow me to knock out the male pieces from the female in order to adjust plumbing.

Any suggestions on how to proceed? I would like to save what I can, even if I'm not going to use it.

 

[Fitter30]

Guess this is hot water and cast radiators. Knowing that your dealing with 103 year old pipe and what year is the boiler? Don't know the age take a few pics of it. Let me guess 2 or three floors 3k sq ft

 

[Sponsor]

 

[sjepps]

Guess this is hot water and cast radiators. Knowing that your dealing with 103 year old pipe and what year is the boiler? Don't know the age take a few pics of it. Let me guess 2 or three floors 3k sq ft

Three floors. 3.5k. Boiler was "upgraded" in the 70s. I'm going to drill out the unions perpendicular to the male and see if I can just break them off. 6" pipe is fun to work with.

 

[John Gayewski]

If your have 6 inch pipe your very likley not going to be able to take it apart without a special tool.

You'd be better off having someone tig weld your changes.

 

[John Gayewski]

You need a 60" one of these. Looks like they are almost $1000.


https://www.ridgid.com/us/en/compound-leverage-wrench

 

[Fitter30]

If you start getting into the 6" piping it will be a very costly very fast. Can zone individual radiators some brands even have smart thermostats. Every radiator doesn't have to.be controlled. Contractor that you would want to call is a design and build mechanical contractor. It would contractor to have a machine that could thread 6". Most if a thread is needed would buy a nipple cut it in half and weld it on after both sides were prepped. The other way that two companies make Grovloc and Victaulic
Roll a groove on the near end of pipe and a bolt together fitting is clamped on. Would need a hi temp gasket to 250° standard is only rated to 150°.

Thermostatic radiator valve - Wikipedia

en.m.wikipedia.org

 

[sjepps]

I ended up using a cut off wheel and a good size punch to crack the unions. Worked perfectly.

 

[Fitter30]

I ended up using a cut off wheel and a good size punch to crack the unions. Worked perfectly.

Try taking two ball peen hammers one the bottom held tight smacking the top and sides of the union. One and two lb hammers with the two on the bottom.

 

[John Gayewski]

Was the question how to split a union? Weren't you asking how to work on 6" threaded pipe? Or how to take it apart without destroying it?

 

[sjepps]

Was the question how to split a union? Weren't you asking how to work on 6" threaded pipe? Or how to take it apart without destroying it?

That was originally the question but it ended up being more adventagous to crack the unions to remove the pipes. I tried heating and cooling for two days and never got them to move, even with a hell of a cheater bar.

 

[John Gayewski]

That was originally the question but it ended up being more adventagous to crack the unions to remove the pipes. I tried heating and cooling for two days and never got them to move, even with a hell of a cheater bar.

Yeah 6"is another beast

 

[Fitter30]

Heat is your friend full size oxy acetylene torch with a big rosebud tip. What size wrench are you using? Steel or aluminum? 12' cheater? Two people, heat, cheater and 2- 4 lb hand sledge. With lots of pressure on the cheater smack the wrench couple inches from the end of the movable jaw. If that doesn't work can sawzall the pipe one close to the fitting and further back so have room to work, cut multiple times length wise the pipe in the fitting without cutting the threads with a half round cape chisel cave the pipe in pull the pieces out. 6" Sch 40 weighs 19 lbs a foot. This 4"-6" pipe die also need a drive shaft ,pipe machine, pipe vise and pipe stands.

Ridgid 36630 Model 161 Receding Geared Pipe Threader, 4 - 6 Inch NPT Capacity [Refurbished]

Ridgid 36630 Model 161 Receding Geared Pipe Threader, 4 - 6 Inch NPT Capacity [Refurbished]

www.b2esurplus.com

Any more unless it's spec would cut, groove a nipple and weld it. Or if there enough room would cut to length, groove it in place if the company owned the tool till you could use screwed pipe 2" or under.

 

[sjepps]

Heat is your friend full size oxy acetylene torch with a big rosebud tip. What size wrench are you using? Steel or aluminum? 12' cheater? Two people, heat, cheater and 2- 4 lb hand sledge. With lots of pressure on the cheater smack the wrench couple inches from the end of the movable jaw. If that doesn't work can sawzall the pipe one close to the fitting and further back so have room to work, cut multiple times length wise the pipe in the fitting without cutting the threads with a half round cape chisel cave the pipe in pull the pieces out. 6" Sch 40 weighs 19 lbs a foot. This 4"-6" pipe die also need a drive shaft ,pipe machine, pipe vise and pipe stands.

Ridgid 36630 Model 161 Receding Geared Pipe Threader, 4 - 6 Inch NPT Capacity [Refurbished]

Ridgid 36630 Model 161 Receding Geared Pipe Threader, 4 - 6 Inch NPT Capacity [Refurbished]

www.b2esurplus.com

Any more unless it's spec would cut, groove a nipple and weld it. Or if there enough room would cut to length, groove it in place till you could use screwed pipe 2" or under.

I got it to where I want it now, I bought stands for the pipe because that's a lesson you only need to learn once I was using a 36" aluminum wrench with a 6' cheater. When I needed to save unions I just cut really close to the nipple then sawzaw'd the inside threads, then punched them out. Fun, messy, tiring job.

 

[Fitter30]

I got it to where I want it now, I bought stands for the pipe because that's a lesson you only need to learn once I was using a 36" aluminum wrench with a 6' cheater. When I needed to save unions I just cut really close to the nipple then sawzaw'd the inside threads, then punched them out. Fun, messy, tiring job.

36" wrench is max for 5". Hanging by couple of threads of the movable jaw nut. Aluminum wrench when the handle breaks its right now. Where steel bends.

 

[sjepps]

36" wrench is max for 5". Hanging by couple of threads of the movable jaw nut. Aluminum wrench when the handle breaks its right now. Where steel bends.

I was using a chain wrench too, maybe I should have gotten a bigger pipe wrench