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Weil McLain WTGO-3 Flue Question

Vin
Vin Member Posts: 4
I have a Weil McLain WTGO-3 in the basement. It is back vented into a standard clay chimney.

My issue...the chimney has been removed because it was falling apart.

I am thinking of installing the new chimney internal. The boiler flue comes out 7 inch. The manual calls for 6 inch round. Weil Mclain support said I can reduce down to 6 inch at the boiler

To install internally, I would need to run a 6 inch flue approx 4 ft vertical before turning up (there is a window on the floor above.) The stack will be about 17 ft in total. 

The stack will be trplie wall flue and framed in.

Question...do you see any issue reducing this boiler flue to 6 inch?

PS...I also have the option to install the flue outside, where the old chimney was and frame in. I am considering installing indoors to improve the appearance of the house.

Thx

Vin 

Comments

  • Vin
    Vin Member Posts: 4
    Weil McLain WTGO-3 Flue Question

    Sorry...this is an oil fired boiler



    thx

    Vin
  • JStar
    JStar Member Posts: 2,752
    Vent

    6" should be fine, according to the GAMA tables.
  • Ron Jr._3
    Ron Jr._3 Member Posts: 603
    Jstar is right

    6 inch round is the minimum for a Weil 3 section . They do allow you to connect the boiler to the chimney in 5 inch too , but I'd keep it 6 . 
  • icesailor
    icesailor Member Posts: 7,265
    Vent Connector:

    The 5" or 6" horizontal vent connector is one issue. The venting in the chimney is another. The length of the chimney comes into play. And what is the tripple wall pipe? Is the inside liner Stainless Steel? Are the outer liners galvanized steel?
  • Vin
    Vin Member Posts: 4
    Weil-McLain-WTGO-3-Flue-Question

    Thanks everyone for your replies,

    Boiler flue is out the back, 7" elbow into a 2' Barometric Flue Damper.

    I would reduce to 6" bend after the damper. The 6" would run vertical about 4 feet, then another bend up....connecting to the triple wall pipe. The triple wall is 6" inside diameter. The first 8' of triple wall is galvanized since it is indoors. I will need to offset the top with 2 30 degree bends to get around a roof rafter (bends are also galv). once through the roof, then about 6' of stainless steel triple wall.

    My concern is the 4' of vertical flue at the boiler to get to the triple wall stack and the 4 bends needed with this layout.

    Thx 
  • Vin
    Vin Member Posts: 4
    Weil McLain WTGO-3 Flue Question

    Sorry folks, I meant to say the 6" would run HORIZONTAL about 4 feet (with about a 30 degreen pitch), then another bend up....connecting to the triple wall pipe. The triple wall is 6" inside diameter and stainless on the inside

    My concern is the 4' of HORIZONTAL flue at the boiler to get to the triple wall stack and the 4 bends needed with this layout.



    Sorry for the confusion...I need more sleep !
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