Improved Radiator Efficiency

[Geno]

My cogen system is working pretty well. When I push it my coolant heatex is a little undersized but that doesn't happen often. The biggest change I've made recently is a modification to the rad in the house.


Hot goes in on the bottom and "cold" comes out the top. I thought the heat would spread throughout the rad and it does to some extent but not well enough. A couple weeks ago I took the bottom fitting off, attached a 3/4" copper pipe which extends 10 ribs into the rad. I capped the end and drilled a 3/8" hole in it. I then drilled 10 or so smaller, decreasing size holes in the pipe leading back to the fitting. I tested it with a garden hose before putting it back in.  It's much more effective this way and the coolant drops about 10°F I don't know if I doubled the heat output but it's got to be close to that.

Thanks, Geno

[mobile_bob]

Geno, i assume you are using a pump to move the hot water with?

if so what pump are you using?

nice looking setup you have there

bob g

[bschwartz]

In a standard system, the hot goes in the top, and cold(er) comes out the bottom.
Why did you reverse your system?

[Geno]

It's a 3 speed Grundfos pump ~70 or so watts on high IIRC. All 3/4" pex.

The flow is that way because at the time I was worried about air being trapped in the top of the radiator and I didn't want to manually bleed it all the time. This way all air goes to the high spot in the loop where it is bled out in the expansion tank. I didn't realize those little automatic bleeders could be had for 15$ or I would have screwed one into the bleed fitting on the rad.

Thanks, Geno