greenwood 100 new install

[lizard]

I just installed a greenwood 100. I have it set up as a closed loop. It has been running since sunday with no real problems. I got up to a clod house this morning and found that my pex pipe bursted at the boiler. Anyone have any idea why. I am controling my boiler with a honeywellt775p2003 digital boiler control. I have max temp set to 180 f. As I have watched the boiler run it get up to about 182-185 then temp start droping. The damper does shut down at 180, it is increase because of residual heat.

Help please I am not sure what to do

 

[maple1]

Were you monitoring pressures?

Do you have an adequate expansion tank?

How close to your boiler is the Pex? Maybe replace with copper near-boiler, if it's near-boiler?

 

[lizard]

I am monitoring presure right at the boiler in my supply line. Also monitoring it in the basement at heat exchanger I have been running 12 psi.

I have a xt-30 expansion tank.

My pex is about 16" from the boiler.

 

[stee6043]

How did your pex "burst"? Did it split in the middle of a section or did it fail at a fitting? Most pex should be able to withstand temps well into the 200's without failing. But it's true that not all pex is created equal. Did you use a name brand? Crimp fittings or compression?

Aside from all the pex talk most folks around this board have used copper or iron pipe for all near-boiler piping. I think it may even be a manufacturers recommendation on some models. If you want to sleep well at night for the next 30 years and not worry about this happening again I'd say tear out the pex and put some black iron in there. Money well spent, easy to work with, DIY friendly...

 

[lizard]

It split just after a shark bit fitting about a 6" split down the middle of pipe. I am using raupex oxygen barrier 1" insulated. I have iron and copper then switches to pex as it leaves my ploe barn and goes into house.

 

[paragonbuilders]

I have a greenwood 200 I just got up and running a few weeks ago and the refractory holds so much heat that even with the damper closed it can overheat very quickly. Mine happened to get a bubble of air at the circulator and it was cavitating. It started producing steam real fast. Fortunately I was there to open the fresh water in valve and get it cooled down. Mine is all cast iron to storage. Pex to the house but at least 15' of pipe away from the boiler. It showed me quick that I need a dump zone plumbed in, in case of pump failure or if Murphy shows up.
Dan

 

[mr.fixit]

Try running with a lower temp setting to allow more headroom for when there is no call for heat.
Mine did that same thing before I had the storage connected.Half a load of wood,no call for heat and boiler temp climbs fast especially if you have good draft. It will only do this if you aren't watching it!

 

[stee6043]

Still seems a bit odd to me. Pex shouldn't be bursting at temps/pressures that do not trigger the pressure release valve on the boiler.

I assume you do have a pressure relief valve?

Any pictures of the area where the failure occured? This might help identify other potential issues.

 

[Jesse-M]

you should have two relief valves, one pressure, one pressure/temp.......and you must have a dump zone plumbed in. I also would turn the aquastat temp down. Make sure the setting on the dump zone aquastat is around 185.

 

[heaterman]

Along with what others have said, my personal opinion is that "shark Bite" type fittings have no place in a boiler system.

 

[Jesse-M]

Along with what others have said, my personal opinion is that "shark Bite" type fittings have no place in a boiler system.

I agree.....