Payne PG95ESA Installation, Start-Up, Operating And Service And Maintenance Instructions Download

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Recommended Combustion Air Inlet Moisture Trap

Recommended to prevent moisture from trickling into the furnace

vestibule, a trap can be installed in the intake air pipe near the
furnace. To prevent moisture, connecting a drain line to the trap is

recommended as trace amounts of moisture will evaporate into the
intake air stream. If the combustion air inlet is located near a

moisture exhaust duct, or there are other concerns of excessive
moisture being drawn into the combustion air inlet, it is

encouraged to connect a drain line to the trap.
The trap can be constructed from a running tee of the same
diameter of the intake air pipe with

EITHER

a removable cap

attached to a 6-inch long pipe connected to the tee or the External
Vent Trap Kit to help prevent contaminants from entering the

furnace. See Fig. 39.
The External Vent Trap Kit accessory may be used as a trap for the
combustion air inlet pipe if a large amount of moisture must be

removed. The drain line may be connected to the same drain as the
furnace condensate and the evaporator coil condensate line

ONLY

if the inlet air trap drain and the evaporator coil drain empty into an
open segment of pipe above the drain. See Fig.17. When using

the External Vent Trap Kit, refer to those instructions for proper

drain connections.
The tee may also be connected to the intake air pipe on the side of

the casing. See Fig. 39.
In any configuration, it will be necessary to add the equivalent

length of the tee (15 feet/5 M) to the Total Equivalent Vent Length

of the venting system.

ADDITIONAL INFORMATION FOR

POLYPROPYLENE VENTING SYSTEMS

Polypropylene venting systems include flexible vent pipe.

These flexible vent pipes have a different equivalent vent

length than straight sections of PVC/ABS DWV vent pipe. Be

sure to make the appropriate deductions from the Maximum

Equivalent Vent Length (MEVL), or additions to the Total

Equivalent Vent Length (TEVL), when applying flexible vent

pipes

polypropylene

venting

systems.

See

the

polypropylene vent system manufacturer’s installation

instructions for details.
When using metric-sized venting systems, use these

equivalencies for obtaining the proper MEVL from the Tables:

Use 2” Vent Tables for 60 mm (o.d.) vent systems

Use 3” Vent Tables for 80 mm (o.d.) vent systems

Use 4” Vent Tables for 100 mm (o.d.) vent systems

NOTICE

The measured length of pipe used in a single or 2--pipe termination
is included in the total vent length. Include deductions from the

Maximum Equivalent Vent Length (MEVL) contained in the

Venting Tables for elbows and flexible vent pipe.

Factory

accessory concentric vent terminations or pipe lengths and elbows

used for “standard” vent terminations do not require a deduction
from the Maximum Equivalent Vent Length. See vent termination

figures associated with Table 16. Include a deduction for a Tee

when used for Alberta and Saskatchewan terminations.

NOTE

: Polypropylene venting systems MAY require additional

deductions from the MEVL, or additions to the TEVL, for vent
terminations and flexible pipe sections. See the polypropylene
venting system manufacturer’s instructions for details on
equivalent lengths of vent terminations and flexible vent pipes,
and for calculating total vent lengths.
To calculate the Total Equivalent Vent Length (TEVL) of the

venting system:

1. Measure the individual distance from the furnace to the ter-

mination for each pipe.

2. Count the number of elbows for each pipe.
3. For each pipe, multiply the number of elbows by the equi-

valent length for the type of elbow used. Record the equi-

valent length of all the elbows for each pipe.

4. If a Tee is used on the termination (Alberta and Saskat-

chewan, when required) record the equivalent length of the
Tee used.

5. Calculate Total Equivalent Vent Length by adding the equi-

valent lengths of the fittings to the lengths of the individual
vent and combustion air pipes.

6. When using polypropylene venting systems with flexible

vent pipes, perform adjustments for the equivalent length of
the flexible vent pipe to the calculated total equivalent

venting system length. See the polypropylene vent system
manufacturer’s instructions for details.

7. Select a diameter of vent pipe from Tables 16 and note the

Maximum Equivalent Vent Length (MEVL) shown for that

application for that specific furnace input size. Compare the
Total Equivalent Vent Length (TEVL) to the MEVL:

8. If the Total Equivalent Vent Length is

shorter

than the

Maximum Equivalent Vent Length for the diameter of pipe
chosen, then that diameter of pipe selected may be used.

9. If the Total Vent Length is

longer

than the Maximum

Equivalent Vent Length for the diameter of pipe chosen,
that diameter pipe MAY NOT be used for venting the
furnace. Try the next larger diameter pipe

NOTE

: If the calculated Total Equivalent Vent Lengths results in

different diameter pipes for the vent and combustion air, select the
larger diameter for both pipes.

NOTE

: If the Maximum Vent Length for diameter of the pipe

selected is longer than the measured length and the equivalent
length of all the fittings and terminations (TEVL), recalculate
Total Equivalent Vent Length using the next smaller diameter. If
the Maximum Equivalent Vent Length is still longer than the
longer TEVL of the vent pipe or combustion air pipe, then that
diameter of pipe selected may be used.
When installing vent systems pipe lengths of 10 ft. (3 M) or less,

use the smallest allowable pipe diameter. Using a pipe size greater

than required for short venting systems may result in loss of
efficiency, incomplete combustion, flame disturbance, or flame

sense lockout.
For vent systems longer than 10 ft. (3 M), any larger diameter vent

pipe shown in Table 16

FOR THAT SIZE FURNACE

may be

used.

Combustion Air and Vent Piping Insulation

Guidelines

NOTE

: Use closed cell, neoprene insulation or equivalent.

The vent pipe may pass through unconditioned areas. The amount
of exposed pipe allowed is shown in Table 15.