John Wood Oil-Fired Direct Vent - Manual (Page 7)

To attach the flex duct to the water heater see Figure 6.
1. Place the band clamp around the transition piece (6”
diameter) of the flex duct.
2. Slide the transition piece over the water heater flue out-
let.
3. Leave a gap of approximately 5/8” to 3/4” between the
edge of the transition piece and the water heater casing
top.
4. Slide the band clamp down so that the gasket
straddles the edge of the transition piece. The crimp of
the clamp must engage the bead on the transition piece.
5. Tighten the gear clamp.
INITIAL START-UP
The burner is equipped with pre-purge and post-purge
control. The pre-purge is set for a timing of 15 seconds,
+5 seconds, -0 seconds. The post-purge is set for 3
minutes.
After the burner has started to fire, allow the heater to
operate for 10 to 15 minutes (from a cold start).
Take a smoke reading. An opening for smoke readings is
provided in the transition piece of the duct (Figure 7).
The smoke must be adjusted to a maximum of # 1 smoke.
With an adjustment of #1 smoke, the overfire pressure
should be between .20” and .25” W.C. Take care to
replace the sealing screw in the overfire pressure test
port to prevent flue gas from escaping from the combus-
tion zone into the home. (Figure 8).
TEST FOR LEAKS
With the heater still running, test around the band clamp
at the flue connection of the heater for leaks. Use a
smoke pencil or similar device. Make sure the clamp is
tight and no flue gases escape at this point.
Repeat the procedure at the connection between the flex
duct and the vent terminal (inside the house). If leakage
is detected, it may be due to misplaced clamps over the
joint. Please repair all leaks.
NOTE: The gasketing material is a special high tempera-
ture Teflon. DO NOT SUBSTITUTE. If more gasketing is
required for repair it can be obtained from this company.
See page 7 for replacement parts.
Figure 6 Figure 7
SMOKE TEST PORT
AND COVER IMPOR-
TANT: REPLACE
COVER AFTER TEST
ENGAGE EDGE OF
CLAMP OVER BEAD
SEAT CLAMP
WITH GASKET
OVER JOINT
SMOKE TEST PORT
AND COVER IMPOR-
TANT: REPLACE
COVER AFTER TEST
TRANSITION PIECE
OF DUCT
Page 6