Taller baseboard enclosures

[vtwoodheater]

Does anyone know of any real performance numbers with taller enclosures? I have spent countless hours searching and reading. Best I can find is "the taller the better", and " around 15% more".

Just wondering if anyone has any data?

Thanks in advance.

 

[tom in maine]

No hard data, but Dick Hill told me that he used to have ME students test the height of enclosures. They would use steam and rather than try to measure the BTU output, they would measure the amount of condensate produced. More condensate, more heat delivered. He felt there was no physical limit to the height performance. He told me they had some very tall enclosures.
I suspect there might be a friction component that will ultimately limit performance.

One way to quantify this would be to check out the performance data that convector manufacturers offer for their different units.
You might be able to work up some valid data.

 

[Fred61]

I would think that the temperature of the fin tube would control the acceleration of the air. Taller housings would only create more friction.

 

[vtwoodheater]

The only real data I could find was the Multi Pak 90 IIRC, 14" vs 21" tall enclosure. Seemed like 15% more BTU delivered.

So if friction is the limiting factor eventually, just making the enclosures as tall as you can without obstructing windows or outlets, is close enough?

 

[tom in maine]

Hotter is better, but if there is any temperature differential between ambient and the fintube, buoyancy is induced and the taller the enclosure, the greater the draft (same as a chimney). Friction is an issue, but that is something an engineer can sort out. I have some worksheets on it somewhere. There are similarities between this and thermosyphon solar hot water systems. Both function on buoyancy. I suspect air is less susceptible to frictional losses than water.
And I do know that taller thermosyphon systems work better.

That about taps out my knowledge or memory on this unless I come across the paperwork on this.

 

[vtwoodheater]

I appreciate the conversation. Just trying to gather some info.

So it seems the taller enclosure the better, there will be some gains made.

If I ever get time, I am going to try it.