Install Instructions

Ratings
Notes:
1. Shield water heaters require special gas venting. Use
only the vent materials and methods specified in the
Shield Installation and Service Manual.
2. Standard Shield water heaters are equipped to operate
from sea level to 4,500 feet only with no adjustments.
The water heater will de-rate by 4% for each 1,000 feet
above sea level up to 4,500 feet.
3. High altitude Shield water heaters are equipped to
operate from 3,000 to 12,000 feet only. The water
heater will de-rate by 2% for each 1,000 feet above sea
level. High altitude models are manufactured with a
different control module for altitude operation, but
the operation given in this manual remains the same as
the standard models. A high altitude label (as shown in
FIG. A) is also affixed to the unit.
Derate values are based on proper combustion
calibration and CO
2
’s adjusted to the recommended
levels.
4. The Shield 286-125 model can be alternatively vented
using a 3" vent/air size. If the 3" vent/air size is used,
the maximum vent/air pipe lengths are limited to 60
equivalent feet each.
7
Maximum allowed working pressure is located on the rating plate.
Model Number
Note: Change “N”
to “L” for L.P. gas
models.
CSA
Input Modulation Btu/hr
(Note 2)
Water Content
Gallons
Water
Connections
Gas
Connections
Vent/Air Size
Min Max
(Note 1,4)
SNR126-065 25,000 - 125,000 62 1-1/2" 1/2" 3"
SNR151-100 30,000 - 150,000 91 1-1/2" 1/2" 3"
SNA151-100 30,000 - 150,000 91 1-1/2" 1/2" 3"
SNR201-100 40,000 - 200,000 92 1-1/2" 1/2" 3"
SNA201-100 40,000 - 200,000 92 1-1/2" 1/2" 3"
SNA286-125 57,000 - 285,000 116 2" 3/4" 4"
SNA401-125 80,000 - 400,000 117 2" 1" 4"
SNA501-125 100,000 - 500,000 117 2" 1" 4"
NOTICE
Figure A High Altitude Label Location
UNIT EQUIPPED FOR
HIGH ALTITUDE
3,000 FT. TO 12,000 FT.
IMG00462
Installation & Service Manual
HLW
LOW LEAD CONTENT