Hi all,

A warm one in Melbourne today mostly kept me out of the shed so I turned my eye to some domestic duties..... sort of;

I figured it was a good day to give the wood heater a good clean and yearly inspection. I knew some of the heat bricks were looking a little worse for wear and also the heat baffle that sits above. These are reasonably easily replaced.

One thing that will also need replacing it what is called the air tubes. These are two tubes with holes along their length. They introduce tertiary air into the firebox to help complete the combustion process to help reduce particulate pollution and increase the efficiency of the heater (stated to be 85%)

Anyway, as can be seen from the pics, one is particularly badly rusted and the other not far behind. I'm keen to replace these since it may affect the effeciency of the heater. I'm sure I could just purchase a new manifold but since it's a bit of tube tack welded to a plate I would feel ashamed if I didn't put to use some of my equipment in the shed to make a replacement myself.

These things glow cherry red when the fire is up to temp so they cycle through quite a wide range of temps on a daily basis in the cooler months.

Question is this;

Should I make them out of stainless, either 304 or 316? The extra cost would be bugger all. I'm thinking they may last a bit longer than the 5 years that these did.

They are only held and fixed at one end. The other end just rests on a plate so thermal expansion and/or buckling will pose no issue.

Thoughts anyone?

Simon



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