noise in wood-fired convection hot water systems

[northsheep]

Thirty years ago I built the system in the photo, consisting of a wood range with a water jacket connected via a convection loop to a tank. Connected to the house water pressure system it provides hot water to sinks and shower in winter when the stove heats the house. Two years ago I moved the system to a new house in another state. In both cases the water comes from a well, although the soil types are different.

Last year in the new house the system worked fine, as it did for years in the previous house. It has always been noiseless. This year the water gurgles and bangs, the water pipe from the stove to the tank is much hotter, and only a quarter of the tank is hot although it used to be 2/3 hot by the end of a day of running the stove.

My theory is that the water jacket is getting clogged, slowing the water movement in the convection loop so that it heats to the point of "flashing off" steam, especially with sudden pressure changes in the house water pressure system that feeds water to the tank and hot water from the tank. And it is the steam that is causing the noise, as with banging in the old hot water radiators. Does this make sense? If so is there a way to flush or otherwise remove mineral buildup in the water jacket?

 

[flyingcow]

I like the set up. Nice work. Other will chime in. this is a good bulletin board, welcome from another Mainer.

 

[arbutus]

We had a gas water heater in our previous house. That house had a problem with iron bacteria, which formed a layer of snot where ever there was standing water. The gas water bubbled, gurgled, popped, and banged when firing, like a steam radiator, because it couldn't naturally convect near the burner due to the bacterial snot.

Can you open an inspection port and see what the inside looks like?

My other guess would be mineral deposits due to hard water.

The only other possibility is that the convection loop is partially plugged.

 

[GENECOP]

Air?

 

[Clarkbug]

Have you gotten your water tested to know whats in it? Knowing if the water is the problem will go a long way towards troubleshooting.