Register Boot size? - DIY Chatroom

Arnj · 01-25-2009, 02:05 AM

I am running 10'' for hot air and 12'' for return air inside from a outside wood furnace, my question is what size of register boot do I need for both of them? I know it will be 10'' and 12'' but by what 10'' X? X? and 12'' X? X? ?

beenthere · 01-25-2009, 08:09 AM

That depends on what BTU rating the wood stove is.
And what air flow they want for it.

Arnj · 01-25-2009, 04:07 PM

They do not list a BTU rating they say there are to many variable factors that can change it . In the manual it says it has a 1800cfm blower and it should have 600 feet to 1000 feet per minute in the main duct and 400 to 600 FPM at the registers. Does this help any?

Dr Heat · 01-25-2009, 04:20 PM

Quote:

Originally Posted by Arnj

I am running 10'' for hot air and 12'' for return air inside from a outside wood furnace, my question is what size of register boot do I need for both of them? I know it will be 10'' and 12'' but by what 10'' X? X? and 12'' X? X? ?

As a general rule of thumb I like to see terminal boots to have 2X the area of the duct this is to allow for the register and the block that it creates.

Now this being a wood furnace better to go large and let the fan move as much air as possible.

10" round = 9x9 sq.
12" round =11x11

So Your 10" trunk would terminate at about 8x20 the 12" 10x 24

These sould put you in the ball park.

Arnj · 01-25-2009, 04:39 PM

Thank you DR HEAT. I found the BTU rating on the furnaces website it is maximum 200,000 I dought this will change the boot size any, but just thought i'd list it. Thanks again

beenthere · 01-25-2009, 09:23 PM

1800 CFM at 1000 FPM, requires an 18" round duct.

If you use 10", you ain't getting much heat out of that wood furnace, before it shuts down.

Your going to need some really big grilles also.

Arnj · 01-29-2009, 02:36 AM

Does anybody know who makes a 8'' x 20'' heat register ? The biggest I can find is a 8x14.Or would it be alright to just use a return grille? I do find them in that size.

Dr Heat · 01-30-2009, 09:44 PM

Quote:

Originally Posted by beenthere

1800 CFM at 1000 FPM, requires an 18" round duct.

If you use 10", you ain't getting much heat out of that wood furnace, before it shuts down.

Your going to need some really big grilles also.

Ya I missed the 1800 cfm

Dr Heat · 01-30-2009, 09:47 PM

Quote:

Originally Posted by Arnj

Does anybody know who makes a 8'' x 20'' heat register ? The biggest I can find is a 8x14.Or would it be alright to just use a return grille? I do find them in that size.

You might need to go to a commercial grill, special order from continental.

Return grills are different they are not designed to distribute the air.