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7077-801F • 08/20
B. Draft
Draft is the pressure difference needed to vent appliances
successfully. When an appliance is drafting successfully,
all combustion by products are exiting the home through
the chimney.
Considerations for successful draft include:
• Preventing negative pressure
• Location of appliance and chimney
To measure the draft or negative pressure on your appliance
use a magnehelic or a digital pressure gauge capable of
reading 0 - .25 inches of water column (W.C.).
The appliance should be running on high for at least 15
minutes for the test. With the stove running on high you
should have a negative pressure equal to or greater than the
number given in the chart. If you have a lower reading than
you find on the chart, your stove does not have adequate
draft to burn the fuel properly.
C. Negative Pressure
NOTICE:
GHP assumes no responsibility for the improper
performance of the chimney system caused by:
•
Inadequate draft due to environmental conditions
•
Downdrafts
•
Tight sealing construction of the structure
•
Mechanical exhausting devices
MODEL
Minimum Vacuum
Requirements
PH35PS-B
0.17 inches W.C.
PH50PS-B
0.17 inches W.C.
PH50CABPS-B
0.17 inches W.C.
E. Tools And Supplies Needed
Tools and building supplies normally required for
installation, unless installing into an existing masonry
fireplace:
- Reciprocating Saw
- Channel Locks
- Hammer
- Phillips Screwdriver
- Tape Measure
- Plumb Line
- Level
- Framing Material
- Hi-temp Caulking Material
- Gloves
- Safety Glasses
- Framing Square
- Electric Drill & Bits (1/4”)
- 1/4” Self-Tapping Screws
May also need:
- Vent Support Straps
- Venting Paint
Correct low draft or low vacuum problems by doing one of
the following:
• Thoroughly clean the exhaust path and venting
(See
Maintenance Section)
.
• Inspect for worn or broken gaskets. Repair any gaskets
suspected of leaking, or adjust the trim.
•
Upper level air leaks such as:
-
Recessed lighting
-
Attic hatch or open windows
-
Duct leaks
To minimize the effects of negative air pressure:
• Install the outside air kit with the intake facing prevailing
winds during the heating season
• Ensure adequate outdoor air for all combustion
appliances and exhaust equipment
• Ensure furnace and air conditioning return vents are not
located in the immediate vicinity of the appliance
• Avoid installing the appliance near doors, walkways or
small isolated spaces
• Recessed lighting should be a “sealed can” design
• Attic hatches weather stripped or sealed
• Attic mounted duct work and air handler joints and seams
taped or sealed
D. Inspect Appliance & Components
• Remove appliance and components from packaging and
inspect for damage.
• Report to your dealer any parts damaged in shipment.
• Read all the instructions before starting the
installation. Follow these instructions carefully
during the installation to ensure maximum safety
and benefit.
Negative pressure results from the imbalance of air available
for the appliance to operate properly. It can be strongest in
lower levels of the house.
Causes include:
• Exhaust fans (kitchen, bath, etc.)
• Range hoods
• Combustion air requirements for furnaces, water heaters
and other combustion appliances
• Clothes dryers
• Location of return-air vents to furnace or air conditioning
• Imbalances of the HVAC air handling system
Risk of Asphyxiation!
Negative pressure can cause spillage of combustion
fumes and soot.
WARNING
!
Inspect appliance and components
for damage.
Damaged parts may impair safe operation.
•
Do NOT install damaged components.
•
Do NOT install incomplete components.
•
Do NOT install substitute components.
Report damaged parts to dealer.
WARNING
!
