Who is making double wall Indirects

The Steam Whisperer · January 29

I have seen more and more companies drop the double wall, though ASME appears to still require them. I am especially interested in those that work would as a hot water loop off a standard low pressure steam boiler. I see Laars has some, but the coils are carbon steel…so probably more prone to corrosion. It would be nice to have stainless steel coils. The Triangle tube units will tend to collect sludge at the bottom, with no way to drain it.

I find them a good fit for 6 flats here in Chicago…. but the heating capacity is limited.

mattmia2 · January 29

looks like htp still makes them.

hot_rod · January 29

How do you feel about reverse indirects?

I've heard they qualify as double walled protection.

Chiltrix has some stainless versions. Turbomax for copper coil type.

I would not suggest a steel coil inside a steel coil. They tend to condense and corrode away between the layers.

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The Steam Whisperer · January 30

I was using the HTP, but I believe I was told they were no longer making the double wall. I looked through thier website and didn't see the double wall models.

Hot Rod, I'll look at those options you've suggested. I haven't come across those yet.

Thank you.

mattmia2 · January 30

I don't know. I would contact HTP. Their web site is very confusing, and large… In some places they mention a double wall hx but don't seem to list models that specifically say double or single wall. I think WM makes their own tanks too, might look there.

Who is making double wall Indirects

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