Page 4
D
RAFT
C
ONTROL
I
NSTALLATION IN
T
YPE
B V
ENT
P
IPE
CAUTION:
DO NOT use the supplied collar when mounting draft
control to Type B Vent Pipe. Install by using a Type B Vent Pipe Tee.
1. Install a vent pipe reducer or increaser into the inner pipe and
fasten using sheet metal screws. (See Figures 6 & 7)
2. The opening of the Type B Vent Tee, at the draft control mounting
location, should be sealed with a high temper- ature sealant or
equivalent.
3. Refer to Insertion of Draft Control Section.
I
NSERTION OF
D
RAFT
C
ONTROL
S
ECTION
Insert the draft control into the collar or tee. The front face of the
control MUST be plumb and the bearing surfaces MUST be level
whether the control is on a horizontal, vertical or sloping flue pipe.
Use a spirit level and level accurately. (See Figures 6 & 7) Secure
the control in the collar by tightening the clamping screws. If a tee is
used or a collar is supplied locally, the control may be held in place
by sheet metal screws.
ADJUSTMENTS
A
DJUSTING THE
D
RAFT
C
ONTROL WITH
4" MG1
The control MUST be adjusted to the desired draft setting by adding
or removing the washer-type weights supported by the two chains on
the side of the draft control. (See Figure 8) DO NOT move the weight
attached directly to the gate, this is used only for balancing at the
factory.
A
DJUSTING THE
D
RAFT
C
ONTROL WITH
5" AF
Vertical Flues Mounting -
The control is shipped for installation in a
vertical flue. The adjustment weight should be in the right hand slot
when you face the control. See Figure 9.
Horizontal Flues Mounting -
For hori-zontal flues, remove the
weight from the right hand slot and attach it to the left hand slot as
shown in Figure 9.
What Draft Setting to Use -
When adjusting the control, two things
are essential:
1. The burner must be operating for at least 10 minutes to obtain
maximum chimney draft.
2. An analysis of the flue gases is necessary to determine the
percentage of CO
2
and check for presence of CO. Refer to the appliance instructions and/or to the local
gas company for the proper CO
2
readings and allowable CO levels. A rule of thumb for draft setting is
between .01" to .03" of water column draft at the appliance outlet. (Check equipment requirement.)
Changes in the adjustment of the 4" MG1 control should be made by adding or removing the washer-like
weights (supplied with the control) to or from the weight holder chain assembly. After the control is adjusted,
it's action will be entirely automatic, the gate will open or close by itself to correct for changes in the draft that
occur in the chimney.
Figure 7
Figure 6
Figure 8
Figure 9
