pinesawyer
ArboristSite Lurker
A few years ago I installed a Harmon wood boiler in my barn and tied it into my oil boiler in my basement. Piped it under the drive about a hundred feet. The Harmon is rated for heating up to 3,000 sq.ft. However, my cabin is only about 1500.
The unit is great and saves me a bundle, but the pressure always ran high. At 190 degrees (where the aquastat is set on wood boiler) my psi is about 30 to 32 inches. Well the pressure release trips at 35. So I am always worried. Some people have told me that kind of pressure is good. Others said no way. Way too high.
Last spring, after throwing my last load of wood in the boiler for the season, I walked away, jumped in my truck and went to work...forgetting to shut the ash pan door. Well the pressure release valve did not release, and I blew both my inlet and outlet and spewed all my antifreeze onto the cold concrete floor. Wife, lookng out the window, thought the barn was on fire. Steam coming out of everywhere.
So this week I have to get the boiler back online. I am making a few modifications. I have two major questions.
One. If I install an inline pressure tank at the wood boiler in addition to the one already inline on the oil boiler, will this reduce my overall pressure.
Two. The pressure release valve failed last spring when I forgot to close the ashpan door. If it had worked as it should have the valve would have just kept popping and knocking the pressure down until the wood in the firebox burned out. Yah, definately not fun, loss of antifreeze and all, but I would not have blown my lines off the boiler. So is it possible to put a back-up pressure release valve in the system or do they make really, really, really good pressure release valves that absolutely do not fail.
I thought they were pretty much all the same.
Any and all thoughts suggestions are appreciated.
Thanks
The unit is great and saves me a bundle, but the pressure always ran high. At 190 degrees (where the aquastat is set on wood boiler) my psi is about 30 to 32 inches. Well the pressure release trips at 35. So I am always worried. Some people have told me that kind of pressure is good. Others said no way. Way too high.
Last spring, after throwing my last load of wood in the boiler for the season, I walked away, jumped in my truck and went to work...forgetting to shut the ash pan door. Well the pressure release valve did not release, and I blew both my inlet and outlet and spewed all my antifreeze onto the cold concrete floor. Wife, lookng out the window, thought the barn was on fire. Steam coming out of everywhere.
So this week I have to get the boiler back online. I am making a few modifications. I have two major questions.
One. If I install an inline pressure tank at the wood boiler in addition to the one already inline on the oil boiler, will this reduce my overall pressure.
Two. The pressure release valve failed last spring when I forgot to close the ashpan door. If it had worked as it should have the valve would have just kept popping and knocking the pressure down until the wood in the firebox burned out. Yah, definately not fun, loss of antifreeze and all, but I would not have blown my lines off the boiler. So is it possible to put a back-up pressure release valve in the system or do they make really, really, really good pressure release valves that absolutely do not fail.
I thought they were pretty much all the same.
Any and all thoughts suggestions are appreciated.
Thanks