Heat Exchanger recomendations???

[Paso One]

I'm looking for some recomendations on what is the best heat exchanger you have installed.

I'm looking to get the most heat transfered into the shop. ( space not an issue)

I have found out some surprising facts with previous experiments.

I have a heat exchanger that is 48 x 40 two row that puts out less heat than a 25 x 33 exchanger that has 3 rows.

Both are fed with 1/2 inch line.

The 48 x 40 have two very strong fans behind them and cool it off very quickly. I have installed the 25 x 33 in front of the 48 x 40 and use the same fans and it does not restrict flow and seems to throw surprisingly lots of heat.

I have a old suspended heat exchanger that is approx 24 x 20 that originally had 1 1/4 inch inlets that I am feeding it with 3/4 inch pex heat is not as good as I expected.

I have also hooked up the Bus radiator that is 6 inches thick and approx 28 x 32 This Radiator pukes out the heat steadily.

What have you found the best factory built heat exchanger???

3 row 4 row large inlets???

Thanks for reading this long post.

 

[mtfallsmikey]

Dunno if mine is "best", but I used Heil coils, have a local dealer, price not bad. 1/2" feed is a little small, need at least 4-5 GPM for them to work right but...ask me again in Jan. when it is bone-a!sed cold!

 

[Paso One]

I had to google heil coils I 'm still not sure what exactly you are using for the exchanger. Do you have any pictures??

 

[mtfallsmikey]

www.goheil.com

House coil: mounted on Miller oil furnace, 65K BTU output (oil)

Shop coil: Recycled Goodman gas furnace, burners, HX stripped out, mounted hydrocoil/secondary circulator. I made this all by my 'lil self!

 

[Paso One]

Okay thanks I have a better idea on what you used.

What size is the coil and what is the inlet and outlet sizes??

p

 

[mtfallsmikey]

You had to ask!...i'm at work, so as best as I can remember:

Model-HWC-1900
56K BTU @180 deg. water, 70 deg. inlet air temp, 4 GPM flow.
15 1/2" x 16" duct size (?..close!)

These are cased coils (in cabinet)...designed to fit on most Heil/Carrier air handlers/furnaces. One side is recessed to fit into air handler, other side is tuened (flared) to fit ductwork/plenum chamber.

 

[mtfallsmikey]

I forgot to post this pic...the finished product.

 

[Paso One]

Are you using 3/4 inch lines coming and going on your heat exchanger??

I am really having a hard time trying to confirm "that size matters"

Does larger lines on the heat exchanger increase the amount of heat or does the GPM thru the heat exchanger produce more heat.

 

[mtfallsmikey]

Yes, i have 3/4" lines going to my HX...and size does matter, as well as the GPM going thru the coil. Just look at the specs on any coil. The following parameters are used to determine the BTU output of the coil:

GPM
Entering dry bulb air temperature (dry bulb)
Entering water temperature
CFM going over the coil

And also, another factor not listed in the specs....ductwork size, and positioning of the coil. Remember, the ratings/specs are done under ideal conditions in a lab. If you have everything else dialed in correctly, but uneven airflow over the coil, all bets are off.

 

[Paso One]

I saw a heat exchanger on a web site that is 25 x 30 that appears to have 2 large tubes for the inlet and outlet ( guessing 1 inch ) that splits out to alternating rows looks like at least six rows. They are claiming 255,000 BTU's

I was hoping someone had some experience with this type of heat exchanger.

My own experimenting shows a big increase ( of heat) from 2 rows to 3 rows

I can imagine the 6 row throws more heat yet.

Does anyone else have thicker than normal heat exchangers?? ( Lots of rows)

I saw this exchanger on www.outdoorwoodfurnaceparts.com Page 7