Tjernlund SS1R SideShot (Discontinued Version - Pre UC1 Universal Control) 8504046 Rev 05/95 - Manual (Page 15)

DRAFT ADJUSTMENT OIL
The SS1-R Vent system will properly vent a wide range of BTU/hr. input capacities. To compensate for different burner capacities,
vent connector lengths and wind conditions it features a draft adjustment located on the outside of the Vent Hood. In general,
positioning the draft adjustment inward will cause the SS1-R to operate at lowest capacity. Positioning the draft adjustment
outward will cause the SS1-R to operate at highest capacity.
IMPORTANT:
The following paragraph describes the initial draft adjustment. It may be necessary to make a slight readjustment to compensate
for various conditions: wind, vent connector resistance, negative building pressure and multiple appliances.
ASHRAE lists the average design factor for wind loads in North America at 15 MPH. Refer to the Draft Adjustment Chart below.
We recommend that the 25 MPH category be used to allow for excursions beyond the 15 MPH average. It is not recommended
for the SS1-R to be terminated on a wall that faces the direction of the prevailing winds. Backdrafts by severe winds can cause oil
odors to remain in the structure and/or interrupt heating equipment operation. If the SS1-R is terminated in a direction prone to
higher winds, or if higher winds are common in your geographic area, use the 40 MPH category to determine the proper draft
adjustment setting. If the draft adjustment is set at the 25 MPH category and sustained winds exceeding 25 MPH are present, the
Fan Proving Switch will act to close the oil solenoid valve. Wind loads referenced are based on straight line winds directed against
the Vent Hood.
DRAFT ADJUSTMENT PROCEDURE:
1) Set the draft adjustment to the appropriate setting based on the above instructions and the Draft Adjustment Chart. Adjustment
is accomplished by loosening both nuts on each side of the Vent Hood and centering both indicators to the desired setting.
Tighten the four nuts to secure the draft adjustment at desired setting.
2) Place the appliance and SS1-R in operation. Measure the over-fire draft. Make necessary adjustments to the primary
air intake and barometric draft control to comply with the over-fire draft requirements of the appliance. The over-fire draft
should be in a range of -.02" to -.04" W.C., with the optimum setting at -.03” W.C. If adjustments to the primary air intake and
barometric draft control do not provide the required over-fire draft, the SS1-R draft adjustment must be repositioned, accord-
ingly. Measure over-fire draft after repositioning SS1-R draft adjustment.
COMBUSTION AIR
Adequate combustion air is vital for proper combustion and for safe venting. Likewise, for proper SS1-R performance, adequate
combustion air must be available to the appliance. Many installers assume adequate combustion air is present, especially in older
homes. In some cases this is a false assumption, because many older homes have been made "tight" due to weatherization. Size
the combustion air opening(s) into the appliance room as outlined NFPA 31/NFPA 211. When installing a SS1-R, it is usually not
necessary to supply any more combustion air than normally required when conventional venting. Common symptoms of inade-
quate combustion air include: Fan Proving Switch short cycling, odor present at the end of burner cycle, outside air enters the
structure through the SS1-R Vent System on SS1-R/Appliance off cycle.
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NOTES: All draft adjustments are approximate. This chart is
to be used for initial draft adjustment only. Subsequent draft
adjustments may be required to compensate for various field
conditions: wind, vent pipe resistance, building pressure,
multiple appliances, etc.
BTU/HR input ratings assume 30% or less excess air for
flame retention burners.
Do not exceed the recommended BTU/HR input range of the
SS1-R.
Under no circumstances shall the minimum draft adjustment
be used for the larger input range of this product.
Improper draft adjustment may result in the dispersion of flue
products (carbon monoxide) into the building interior.