I am now running 125 psi in my floor heat and its no better....

[bassman]

I have an owb and it is non pressurized and all the local boiler guys and plumbers are always saying that a system that is pressurized is better .
so I installed a tank and plate exchanger for my in floor heat and plumbed in a air nozzle and filled it to 125 psi.
it heats no better than it did with no pressure .
again I have busted a myth.
shayne

 

[ericjeeper]

the only thing "Better" about a closed system

Is no oxygen coming into play havoc with the water or mix.
125 is NUTS?? Get that off of there before you bust a pipe.20-30 psi is all you need or want.

 

[ASEMASTER]

air trap

you may have air traped in your system put a bleed in at the high points.
there is no way you need that kind of pressure and that is supposed to be water not air pressure.

 

[Ken05]

Domestic hot water baseboard systems run at 2-3 psi. At work I have a high pressure steam boiler that runs at 120 psi and 355 degrees f. The piping is all done in schedule 80 black iron.
Can you say BOOM!

 

[trimmmed]

Let some of that air out now! 125 psi is way high. I think mine is @ 20 psi.

Do you have an air scoop on the system? In the area that is not heating, is the water circulating through those pipes?

 

[mga]

hot water baseboard heat is not the same as boiler steam heat. boiler steam heat is exactly that: steam heat under pressure. very few homes still use that type of heat because it's dangerous for houses. usually only industry uses that.

home "boilers" are just hot water heaters, but are often called "boilers". they don't boil the water like an industrial steam boiler does. home systems just heat the water up to around 195 degrees. home systems are designed to relieve itself if the water pressure reaches 30 PSI. as a general rule they run around 15 when hot. 30psi is so that you don't blow your house up with steam heat.

an OWB also heats water, but is often an "open" system...meaning that the only water pressure should be from the pump. most of the guys here know what the normal pressure should be in an average OWB.

if you're running at 125 PSI, then ken05 is correct: you're sitting on a bomb and you're risking not only your life, but family as well. additionally, IF something were to happen because you altered your system, you might have the fight of your life with the insurance company.

 

[RaisedByWolves]

The copper pipes, when properly installed should handle that pressure fine. The rest of the system???


As far as this making a good bomb, well, Yes and No. Vessel pressure testing is done at extremely high pressures without great risk of explosive depressurization due to the method of completely filling the vessel with water. Water is not compressible, therefore if the vessel ruptures under pressure it dosent explode but rather goes SQUCT! and Immediately releases all pressure.


In the case of the heating system, the only danger due to pressure is in the pocket of air which is in the system. If theres a pint sized pocket of air and the system ruptured, you would probably hear it rupture, but it wouldn't do so violently.



If there were gallons of air, you would certainly have a problem.




Heres a good site full of info, just select the proper type of pipe, they state 300-400psi as an average.


http://www.copper.org/applications/plumbing/techref/cth/tables/cthindex_table.htm






.

 

[mga]

good info, RBW, but one has to consider the installation of any system.

not that i'm saying bassman doesn't know what he's doing, obviously he does, but just in case some others are reading this at least we can put them on a safe track if they are going to try any home improvements to a boiler system.

true, it may not be an actual explosion if anything bursts from pressure, but the mess from the water alone is enough of a concern.

 

[bassman]

let it all out and I am now running about 2 psi.
all is well .
floor heat is the way to go .
dogs and cats love it and the wife wishes it was done in all rooms of the house .

 

[ericjeeper]

Bassman

I have 3200 sq. feet of hydronically heated house. Yes it is the most comfortable heat I have ever lived in. I would keep 20 psi in the system that way you can watch for leaks. Enjoy the heat

 

[goblin]

Back in the day almost all large office buildings in the northeast were heated with huge steam boilers. Even large residential buildings were. Man, those cast iron radiators could get hot too.

 

[ktm250rider]

Check out mythbusters where they blast the 40 gal water heater close to 500 feet in the air. Pretty darn cool if you ask me.

 

[LNG24]

The problem with charging your hotwater system to 125psi. The solder was not pressure tested at that rating so you don't know if it will hold or not and the walls are covered up so if it does pop, you wont know it until its too late. However, if it lest go at a baseboard and someone is there...well can you say OOOOWWWWW. Some sever burns will result!