58SP0A/58SP1A: Installation, Start–Up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
27
A190272
Fig. 45 – Furnace Setup Switch Description
A200303
Fig. 46 – Airflow Selection (based on 350 CFM/TON) for A/C (SW2-6, 7, 8) and *CF (SW2-3, 4, 5)
A93059
Fig. 47 – Orifice Hole
2. Determine the correct orifice and manifold pressure adjustment. All
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
d. Find closest natural gas heat value and specific gravity in
.
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.
NOTE:
If orifice hole appears damaged or it is suspected to have been
redrilled, check orifice hole with a numbered drill bit of correct size.
Never redrill an orifice. A burr-free and squarely aligned orifice hole is
essential for proper flame characteristics.
g. Replace orifice with correct size, if required by
. Use
only factory-supplied orifices. See EXAMPLE 1.
3. Adjust manifold pressure to obtain correct input rate, see
SW1
OFF
ON
1
1
SW2
C/
A
F
C
OFF
ON
OFF
DLY
TST
CFM
C/E
RCL
TWN
CFM
4T-045/4T-070
3T-045
5T-070 /
090 / 110
DEF.
DEF.
1.5T
2T
2T
2.5T
2.5T
3T
3T
3.5T
3.5T
4T
4T
5T
4T
DEF.
1.5T 2T 2.5T 3T
3T 3T
3T
5.5T
A/C OR CF AIRFLOW BASED ON COOLING UNIT TONNAGE (FOR PWM MODELS)
2
2
2
1
1
1
6 7 8
OFF
6 7 8
OFF
6 7 8
OFF
6 7 8
OFF
6 7 8
OFF
6 7 8
OFF
6 7 8
OFF
6 7 8
OFF
3 4 5
OFF
3 4 5
OFF
3 4 5
OFF
3 4 5
OFF
3 4 5
OFF
3 4 5
OFF
3 4 5
OFF
3 4 5
OFF
CF
AC
1. Default A/C airflow when A/C
switches are in OFF position.
2. Default Low stage A/C airflow
when CF switches are in OFF position.
MODEL
SIZE
CAUTION
!
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,
.
BURNER
ORIFICE