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Need advice on custom system

Casey150 Member Posts: 1
I'm trying to help my parents restart a boiler system that has not been used in about 4 years. It's in a vacation home which hasn't gotten much winter use.  The last time it was used, one of the baseboards sprung a leak, but I have used the valves to isolate that loop, and it doesn't leak anymore. 

The system is wood fueled.  I believe the prior owner of the house was a pipe fitter and welder, and he built and used the system for many years. 

It is a gravity fed system, but appears to have a circulator on the loop that is turned off. The problem is that I am able to heat up the wood stove, and that in turn heats up the main tank.  However, the water temperature in the wood stove will get very hot (over 200F) but the main tank will only increase in temperature to about 82F.

There is a valve which controls the flow from the stove to the main tank, but if I open it too much I get a water hammer.  The radiators and baseboards do not become warm. 

I drained the expansion tank, which, as far as I can tell, is not otherwise vented to the outside.  The system pressure reads 18 psi when cold, and around 22 when it "warms up." 

I need to know why the system will not warm past 82F, and why the baseboards and radiator will not warm up. I would think that because they are highest, the warm steam would heat them first. 

I do not know the water level of the main tank, not even how I might check it.

Any help would be very much appreciated, as I am a novice when it comes to home heating.

I have made a diagram of the system, here:

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  • lchmb
    lchmb Member Posts: 2,997

    Is there a circulator to move water from the wood boiler to the storage tank? I'm wondering if the closed zone did more to help the system and with it shut down the entire system will not function...Then again, do you know if it ever worked or someone just said it used to?
  • EricAune
    EricAune Member Posts: 432
    Likely not hammer

    When you open the valve on the supply from the wood boiler you are probably hearing the water flash to steam.  This is potentially dangerous, I strongly recommend having a professional take a look at it.  There are many available on this site, just click the 'Find a Contractor' button above.
    "If you don't like change, your going to like irrelevance even less"
  • LarryC
    LarryC Member Posts: 331
    Open the valve to the stove!

    Do like ERIC stated, get a professional in there !!

    I agree that the valve to the stove needs to be opened to start the gravity flow into the main tank.  It was probably installed to prevent to loss of heat up the chimney when the fire went out.


    If you are hearing the "water hammer" or the water flashing to steam, you are playing with some very dangerous conditions.  Steam occupies approximately 1700 times the volume of an equivalent amount of water.  When the volume changes that much, that can create a LARGE amount of force.  Boiler explosions have been deadly.


    For your safety and for  the safety of the family, get a qualified heating professional to examine the system.
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