So it sounds like you have the return air hooked up...that may be the difference.
I bet you would be surprised how much the filter restricts flow with gravity heating....even a clean filter.
Yes- this is why one of the 8" outlet ducts are cold and one hot before the fan kicks in on a cold start up - gravity flow would rather go that way then though the filter.
 
	 
	 
 
		 
 
		
![[Hearth.com] Everything Drolet Tundra - Heatmax...](/talk/data/attachments/192/192442-d84b02cbfb392b3b8d8b4a4a39ab8763.jpg?hash=8Ur_jT-zLa) 
			 
 
		 . Its nothing more than an extension to prevent the rubber hose from melting. Any bends u see in it were just to hold it in position. I rigged it up quick an re located it again leaving pipe bent. Brenn sends me this draft measuring thingy an i had to call him to figure out how to use it properly lol but all i had was a short fitting an a rubber hose w the kit so i grabbed the first piece of metal tube i could find, jammed it on over fitting an foil taped it planning on a more permanent connection that never got done an just aint really needed. I have a camera setup on the dials an was monitoring draft speeds thru out burns to move along faster in understanding were temps would be at dif draft readings. I can remotely monitor an control the entire setup from my phone. T stat, temp controller, power all of it has remote controlling capabilities using my phone an wifi junk. I been meaning to set up a over fire alarm just hadnt got around to it. I do have power loss alarms that go to my phone so I can run home if power goes out. Planning on a battery backup system ive found that will run tundra for about a day if power goes out. Charges an grid power runs thru. No kids no wife no life lol just me an the stove lmao
. Its nothing more than an extension to prevent the rubber hose from melting. Any bends u see in it were just to hold it in position. I rigged it up quick an re located it again leaving pipe bent. Brenn sends me this draft measuring thingy an i had to call him to figure out how to use it properly lol but all i had was a short fitting an a rubber hose w the kit so i grabbed the first piece of metal tube i could find, jammed it on over fitting an foil taped it planning on a more permanent connection that never got done an just aint really needed. I have a camera setup on the dials an was monitoring draft speeds thru out burns to move along faster in understanding were temps would be at dif draft readings. I can remotely monitor an control the entire setup from my phone. T stat, temp controller, power all of it has remote controlling capabilities using my phone an wifi junk. I been meaning to set up a over fire alarm just hadnt got around to it. I do have power loss alarms that go to my phone so I can run home if power goes out. Planning on a battery backup system ive found that will run tundra for about a day if power goes out. Charges an grid power runs thru. No kids no wife no life lol just me an the stove lmao
 Dan
 Dan
 
 
		 
 
		 
 
		![[Hearth.com] Everything Drolet Tundra - Heatmax...](/talk/data/attachments/192/192530-85edf9bd1bc30c408b4317ffb5c26792.jpg?hash=mMEWPN7bGC) 
			![[Hearth.com] Everything Drolet Tundra - Heatmax...](/talk/data/attachments/192/192531-4b9226b9467d3e4c64295dfea8ec4007.jpg?hash=l-5jQA9eci) 
			![[Hearth.com] Everything Drolet Tundra - Heatmax...](/talk/data/attachments/192/192532-3a9bba290fcf6b046419242b2d1bb90d.jpg?hash=JKLv3sVg_V) 
			 
 
		 So far the house heats right up and I have not seen any ill effects due to the 45's. I may consider changing it however since my insurance will want a few pics of the install.
 So far the house heats right up and I have not seen any ill effects due to the 45's. I may consider changing it however since my insurance will want a few pics of the install. 
 
		