Purchased a big Maxx 50k btu heater and now need to figure out the venting. I would prefer to vent through the roof but I will need to run a section an 8 ft section at a 45 degree angle to get the pipe away from the second level. If I recall, the exhaust must not be lower than any window or vent. As you can see in the pic below, I am planning to come out near the top of the roof. Does anyone see issues with this? Any concerns running pipe at 45 degree angle to achieve proper vertical venting? Thanks!
Venting experts
- Thread starter wiegs1
- Start date
D45
Well-known member
It depends on the roof pitch as well
75gmck25
Well-known member
Most heating appliances have an installation guide that lists the max vent length, including some adjustments for the number of 45 or 90 degree angle fittings. I would just follow the manufacturer's recommendation, and my guess is that your installation will be fine as long as you keep it the required distance from that window.
If you look at the Duravent catalog online there is a page that lists the length of pipe needed to jog a vent over x inches with two 30 degree elbows. For example, IIRC I had to use two 30 degree 5" B-vent fittings and a 24" pipe between them to move my vent over 16" to the next joist bay. The table also showed the total vertical rise/space of about 36" that was needed from the top to bottom of the 30 degree elbows.
Bruce
If you look at the Duravent catalog online there is a page that lists the length of pipe needed to jog a vent over x inches with two 30 degree elbows. For example, IIRC I had to use two 30 degree 5" B-vent fittings and a 24" pipe between them to move my vent over 16" to the next joist bay. The table also showed the total vertical rise/space of about 36" that was needed from the top to bottom of the 30 degree elbows.
Bruce
Last edited:
That was my plan. B vent all the way with two 45 degree elbows. My pitch is 9/12.
They make adjustable lengths for B-vent. Makes it a tad easier to hit your roof penetration.to lay out your offset take the center to center measurement and multiply by 1.414. Take that product and subtract the center to make in on the two 45's.
danski0224
Well-known member
Just to avoid any confusion, it is against code to use single wall pipe for a flue in an enclosed attic space.
Type B vent installations in an insulated attic require a spacer to keep insulation at least 1" from the B vent.
PWC Repair
Well-known member
Yes, it's all spelled out under "venting" in the installation manual. They don't specify vertical total BUT they DO specify total length of 30ft for horizontal. I'm sure vertical should be a bit more. Also every 90 counts as 5ft of pipe so two 45's counts as 5ft of your total allowable length. Also distance above roofline and such is also in there. I know it's hard for most men but read the instructions.
danski0224
Well-known member
It's also easier to ask random strangers on the internet, instead of opening up the factory supplied kneepads (aka instructions).
Wow... thanks for being a jerk fellas. Karma is a *****!!!
And for the record, I did read the instructions before asking but they are not clear.
GFY
danski0224
Well-known member
Guess I'm on the opposite side of the fence, because I've found the flue venting portion of the instructions to be quite specific and detailed.
So, GFY back atcha
So, GFY back atcha