Longer Vent Runs - Munchkin HIGH EFFICIENCY HEATER with the "925" Controller Operating Instructions Manual

Do not exceed the 85 foot maximum requirement (intake plus exhaust piping added
together) including fitting allowance.
Example: Installation requires the following material for both inlet and exhaust piping for the
Munchkin
Required: 4 Pcs. (2" or 3") 90 degree elbow (4 x 5 = 20 Equivalent Feet) = 20 Equivalent Feet
Required: 20' of (2" or 3") Plastic PVC Pipe (20 x 1 = 20 Equivalent Feet) = 20 Equivalent Feet
Total Friction Loss in Equivalent Feet (20 + 20 = 40 Equivalent Feet) = 40 Equivalent Feet
C. LONGER VENT RUNS
The connection of the air inlet and exhaust vent at the heater must remain at the standard vent size
from the unit (2" for the T50/T80) (3" for the 80M/140M/199M). If a transition is required, it must occur
at a minimum of 15 equivalent feet for both intake and exhaust. Then transition to the next size pipe.
See the friction loss equivalent table to apply longer vent runs. The overall extended combined
length of pipe on the inlet and exhaust must not exceed 125 equivalent feet total.
Transitioning from 2" to 3" or 3" to 4" should be done in the Vertical position to avoid
condensation blockage. If done in the horizontal position check to make sure
condensation blockage will not occur.
Example: Installation requires the following material for both the inlet and exhaust piping when
extending the vent run for the Munchkin.
3" Vented Appliance
2 Pcs. – 3" 90 degree elbow
20' of 3" Plastic PVC Pipe
Total of 3" Equivalent Piping with Fittings
Transitioning to 4" Venting
6 Pcs. – 4" 90 degree elbows
4 Pcs. – 4" 45 degree elbows
40' of 4" Plastic PVC Pipe
Total of 4" Equivalent Piping with Fittings
Total Friction Loss in Equivalent Feet for both 3" and 4"
Friction Loss Equivalent in Piping and Fittings
Fittings or Piping
90 degree elbow
45 degree elbow
Coupling
air inlet tee
Plastic Pipe
concentric vent kit
V500 or V1000 vent kit
CAUTION
CAUTION
(2 x 5 = 10 Equivalent Feet)
(20 x 1 = 20 Equivalent Feet)
(6 x 3 = 18 Equivalent Feet)
(4 x 1 = 4 Equivalent Feet)
(40 x 1 = 40 Equivalent Feet)
(30 + 62 = 92 Equivalent Feet)
Equivalent Feet
= 5
= 3
= 0
= 0
= 1
= 3
= 0
VENTING
= 10 Equivalent Feet
= 20 Equivalent Feet
= 30 Equivalent Feet
= 18 Equivalent Feet
= 4 Equivalent Feet
= 40 Equivalent Feet
= 62 Equivalent Feet
= 92 Equivalent Feet
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