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chocabloc

intake+extraction size, intake/extraction thru chimney?

Hey there,

So I have a number of questions related to my enviroment which I will try and number to make it easier.

Ok so my plan is a 1kw parabolc in a 1.2 x 1.2 x 2.2 metre tent (green qube). Using DWC ( 2 100litre coolers) and SMS Hybrid controller.

Now my original plan was to get an 8" RVK L1 so I could upgrade in future if neccessary. However I have been advised that it is too big for tent my size even on controller. I read that a fan shouldnt be turned below 40% and was told that an 8" would be, especially in winter. This will cause it to burn out.

So I have a number of options. There is a vent in the bedroom where the chimney was (fireplace was taken out recently as we got the whole house plastered and vent is now there instead). I can intake from the fireplace and extract into the room or else extract through the fireplace. This is a close family members house so I cant do anything major. Beneath the vent the hole is about 7 inches long and 3 to four inches high. Now this doesnt fit the 6" or 8" ducting.

1. Can I cut through this plasterboard to make it bigger (under the vent it is just plaster board and hasnt been skimmed over like the rest of the wall)?

2. Will intaking through the fireplace bring in nasties (even with bug catcher over it)? Will it be stale air?

3. I can extract through the chimney and intake from the room. Also I could possibly put black out lining on the window in the the room with net curtains in front of it fro summer. Cut a hole and attach spigot to the black out lining as a fresh air intake. Issue with this is I would prefer not to keep the window open all the time and im afraid that houses across the way (20 feet) might see that it doesnt look right.

4. Will extracting through the chimney cause lots of condensation in winter time due to hot air meeting cold. Im afraid of water streaming down the chimney as it isnt my house. Chimeny isnt shared with neighbours im pretty sure. I have heard people mentioning dryer vents not sure exactly what they are or how they work. Have found some on ebay i think but only 4". I think this might work. Its a condensation trap. (Description: 10mm, 125mm and 150mm Condensation Traps, for fitting in vertical rigid PVCu pipe ducting. Must be used where pipe ducts pass through unheated roof voids. Fitted with 20mm pipe connection for running off condensate. Not suitable for use with flexible ducting.) I know it says not useable for flex ducting but im sure i could fashion something. http://www.vent-axia.com/range/condensation-trap.html

4. What size extraction/intake is needed for a 1kw. I want to dial it down with a controller to make it alot more quiet. I was hoping a 6" RVK L1 (Ruck Rvk 150 - L1 = 715 m3) would be enough but have been advised it might not be enough to even properly extract the heat, never mind dial it down. So I can get an intake no problem. Should I get the 6 inch A1 (Ruck Rvk 150 - A1 = 470 m3) for intake? Would that be correct and would it be enough to dial it down but not be too much so that it will be dialled down too much during winter etc? I could get the 8" RVK (1000 cfm) but i wont have the height for it or the filter in the tent i reckon so id need to vent into the room im in.

Think thats all for now anyway. Cheers for any replies. Ill like all comments too :-)

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I'd suggest 6"L1 out and probably the A1 out as you suggest. Maybe even 5"A1 to allow for the restriction from the Carbon filter to allow for negative pressure.

In winter it would be likely best to extract through chimney and in summer months intake and try to blow into room with window open. If their is a fireplace downstairs stuff a cushion or pillow up it so the air goes upwards and not up and down into the room below.

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Fireplace is the same downstairs. Just a vent there that I can close. Presume that is okay? They say a carbon filter is 25% so that would make the L1 536 cfm which is only 60 cfm above the lower powered 6". With ducting and bends etc you might be right in needing the smaller fan. Im afraid if i go smaller though I wont be able to turn down the fan.

Where my chimney vent is, the hole is probably seven inches wide. Realised this is too big even if i tried to cut it into a circle rather than the rectangle it currently is.

Reckon duct taping a box over the hole and attaching the duct to the box would suffice for extraction up through?

I know the only way to know for sure is to buy the gear but its costing me 1500 euro plus prob 5- 700 I already spent so wanna be sure.

Cheers Deranged

Also if anyone knows about cutting through the plaster board and whether there will be condensation in the chimney would appreciate input. Or anything to add to derangeds comment

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