Bulletin 549-A
This bulletin should be used by experienced personnel as a guide to the installation and maintenance of AM-91A,
-92A, 93A; AMAF-91A, -92A, -93A; AMEF-91A, -92A, -93A; FSA-91A, -92A, -93A; VSA-91A, -92A, -93A direct area humidifi ers. Se-
lection or installation of equipment should always be accompanied by competent technical assistance. We encourage you to contact
Armstrong or its local representative if further information is required.
Installation and Operation
AM-91A, -92A, 93A; AMAF-91A, -92A, -93A; AMEF-91A, -92A, -93A;
FSA-91A, -92A, -93A; VSA-91A, -92A, -93A
Humidifi ers for Direct Area Humidifi cation
Step 1. Check Shipment Against Packing List
All components are listed on the packing
slip. Report any shortages immediately. If
the humidifi er or accessories have been
damaged in transit, notify us and fi le claim
with the transportation company.
Step 2. Mount the Humidifi er
Support it from the ceiling, Fig. 1-3, or bracket
it to a column as shown in Fig. 1-4. There are
holes on both sides of the humidifi er for mounting
purposes.
Exception: Where supply and return connections
for the 91 & 92 size are short, a pipe hanger to
the steam supply line should be suffi cient.
Figure 1-3.
Figure 1-4.
Humidifi er suspended from ceiling. Humidifi er bracketed to column.
*Standard spring — furnished when no spring range is specifi ed.
AM, VSA Models
AMEF, AMAF,
FSA Models
Figure 1-1.
Figure 1-2.
Dimensions, Armstrong Area Humidifi ers. Fig. 1-1 VSA, AM models do not
have fans. Fig. 1-2 FSA, AMEF models have electrically operated fans. AMAF
models utilize air powered fans.
Installation Procedure
B
C
DF
J
E
H
G
C
D
F
B
J
E
Table 1-1
Model No. B C D E F G H J
AM-91A 15-15/16” 3-3/8” 3-13/16” 6-1/16” 3-1/16” — — 13-1/4”
AMAF-91A 15-15/16” 3-3/8” 3-13/16” 6-1/16” 3-1/16” 15-5/8” 14-9/16” 13-1/4”
AMEF-91A 15-15/16” 3-3/8” 3-13/16” 6-1/16” 3-1/16” 18-9/16” 15-3/4” 13-1/4”
FSA-91A 10-7/8” 3-3/8” 3-13/16” 6-1/16” 3-1/16” 17-3/8” 15-3/4” 13-1/4”
VSA-91A 10-7/8” 3-3/8” 3-13/16” 6-1/16” 3-1/16” — — 13-1/4”
AM-92A 15-15/16” 3-3/8” 3-13/16” 6-1/16” 3-13/16” — — 13-1/4”
AMAF-92A 15-15/16” 3-3/8” 3-13/16” 6-1/16” 3-13/16” 15-5/8” 14-9/16” 13-1/4”
AMEF-92A 15-15/16” 3-3/8” 3-13/16” 6-1/16” 3-13/16” 18-9/16” 15-3/4” 13-1/4”
FSA-92A 10-7/8” 3-3/8” 3-13/16” 6-1/16” 3-13/16” 17-3/8” 15-3/4” 13-1/4”
VSA-92A 10-7/8” 3-3/8” 3-13/16” 6-1/16” 3-13/16” — — 13-1/4”
AM-93A 25-1/2” 4-5/8” 4-3/4” 9” 4-3/4” — — 24”
AMAF-93A 25-1/2” 4-5/8” 4-3/4” 9” 4-3/4” — 17-3/4” 24”
AMEF-93A 25-1/2” 4-5/8” 4-3/4” 9” 4-3/4” 21” 18-1/4” 24”
FSA-93A 20-3/8” 4-5/8” 4-3/4” 9” 4-3/4” 21” 18-1/4” 24”
VSA-93A 20-3/8” 4-5/8” 4-3/4” 9” 4-3/4” — — 24”
Table 1-2
Note: AM models 91, 92 and 93 shown on this bulletin are furnished with
Armstrong C-1801 pneumatic operators. Operator Spring Ranges for
pneumatically controlled humidifi ers.
Armstrong C-1801
Operating Range Adjustable Start Points
5 lbs. 3 psig min. - 6 psig max.
*10 lbs. 3 psig min. - 6 psig max.