Carrier 58ST - Adjustments

35
CAUTION!! FOR THE FOLLOWING APPLICATIONS, USE THE MINIMUM VERTICAL VENT HEIGHTS AS SPECIFIED
BELOW.
FOR ALL OTHER APPLICATIONS, FOLLOW EXCLUSIVELY THE NATIONAL FUEL GAS CODE.
FURNACE
ORIENTATION
VENT
ORIENTATION
FURNACE
INPUT (BTUH/HR)
MINIMUM VENT
DIAMETER (IN.)*
MINIMUM VERTICAL VE NT
HEIGHT (F T.)**
Downflow
Vent elbow left, then
up Fig. 36
154,000 132,000
110,000(036/--- 12 only)
5 12
Horizontal Left
Vent elbow right,
then up Fig. 39
154,000 132,000 5 7
Horizontal Left
Vent Elbow up Fig.
40
154,000 132,000 5 7
Horizontal Left
Vent elbow right Fig.
41
154,000 5 7
Downflow
Vent elbow up then
left Fig. 34
110,000 (036/---12 only) 5 10
Downflow
Vent elbow up, then
right Fig. 37
110,000 (036/---12 only) 5 10
* 4 in. inside casing or vent guard
** Including 4 in. vent section (s)
NOTE: All vent configurations must also meet National Fuel Gas Code venting r equirements NFGC
8. Secure vent connector to furnace elbow with (2)
corrosion--resistant sheet metal screws, spaced approximately
180° apart.
9. Secure all other single wall vent connector joints with (3)
corrosion resistant screws spaced approximately 120° apart.
Secure Type-- B vent connectors per vent connector
manufacturer’s recommendations.
10. The total height of the vent and connector shall b e at least seven
ft. for the 154,000 Btuh gas input rate model when installed in a
downflow application with furnace elbow turned to left side with
the connector elbow outside furnace casing pointing upward.
(See Fig. 36.)
Step 3 —Adjustments
FIRE HAZARD
Failure to follow this warning could result in injury, death
and/or property damage.
DO NOT bottom out gas valve regulator adjusting screw.
This can result in unregulated manifold pressure and result
in excess overfire and heat exchanger failures.
!
WARNING
FURNACE DAMAGE HAZARD
Failure to follow this caution may result in reduced furnace
life.
DO NOT redrill orifices. Improper drilling (burrs, out--of
round holes, etc.) can cause excessive burner noise and
misdirection of burner flames. This can result in flame
impingement of heat exchangers, causing failures. (See Fig.
48.)
CAUTION
!
TABLE 8—ALTITUDE DERATE MULTIPLIER FOR
U.S.A.
ALTITUDE PERCENT DERATE MULTIPLIER
(FT.) OF DERATE FACTOR*
0–2000 0 1.00
2001–3000 8–12 0.90
3001–4000 12–16 0.86
4001–5000 16–20 0.82
5001–6000 20–24 0.78
6001–7000 24–28 0.74
7001–8000 28–32 0.70
8001–9000 32–36 0.66
9001–10,000 36–40 0.62
* Derate multiplier f actors are based on midpoint al titude for altitude
range.
Furnace gas input rate on rating plate is for installations at
altitudes up to 2000 ft.. Furnace input rate must be with in +/-- 2
percent of furnace rating plate input.
1. Determine the correct gas input rate.
In the U.S.A.:
The input rating for altitudes above 2,000 ft.. must be re-
duced by 4 percent for each 1,000 ft.. above sea level. For
installations below 2000 ft.., refer to the unit rating plate.
For installations above 2000 ft.., multiply the input on the
rating plate by the derate multiplier in Table 8 for the cor-
rect input rate.
In Canada:
The input rating must be derated by 10 percent for alti-
tudes of 2,000 ft.. to 4,500 ft.. above sea level by an autho-
rized Gas Conversion Station or Dealer. To determine cor-
rect input rate for altitude, see example 1 and use 0.90 as
derate multiplier factor.
EXAMPLE 1:
88,000 BTUH INPUT FURNACE INSTALLED AT 4300 FT.
Furnace Input
Rate at Sea Level
X Derate Multiplier
Factor
= Furnace Input
Rate at Installa-
tion Altitude
88,000 X 0.90 = 79,200
2. Determine the correct orifice and manifold pressure
adjustment. There are two different orifice and manifold
adjustment tables. All models in all positions, except Low
NOx models in downflow or horizontal positions, use
Table 12 (22,000 Btuh/Burner).
Low NOx models in the downflow or horizontal positions
must use Table 13 (21,000 Btuh/Burner). See input listed
on rating plate.
a. Obtain average yearly gas heat value (at installed
altitude) from local gas supplier.
b. Obtain average yearly gas specific gravity from local
gas supplier.
c. Find installation altitude in Table 12 or 13.
d. Find closest natural gas heat value and specific gravity
in Table 12 or 13.
e. Follow heat value and specific gravity lines to point of
intersection to find orifice size and manifold pressure
settings for proper operation.
f. Check and verify burner orifice size in furnace.
NEVER ASSUME ORIFICE SIZE. ALWAYS
CHECK AND VERIFY.
g. Replace orifice with correct size if required by Table
12 or 13. Use only factory--supplied orifices. See
EXAMPLE 2.
58ST