6
ALTA
Combi Installation, Operating & Service Instructions
110327-04 - 1/22
3
Specifications
Space Heating Ratings
Domestic Hot Water (DHW) Ratings
1
Model
Number
Input
2
(MBH)
DOE
Heating
Capacity
(MBH)
AHRI
Net
Rating
3
(MBH)
AFUE
Input
2
(MBH)
Hot Water Draw Limits GPM (L/min)
2
Min
Max
Min
Max
Max
Min
4
70°F
(39°C)
Rise
77°
(43°C)
Rise
90°F
(50°C)
Rise
ALTAC-136
13.6
120
112
97
95.0
13.6
136
3.7 (14)
3.4 (13)
2.9 (11) 0.5 (2)
ALTAC-200
20
150
141
123
95.0
20
200 5.2 (19.6) 4.7 (17.8) 4.0 (15) 0.5 (2)
1
DHW ratings are not AHRI certified.
2
Input and DHW draw limits for elevations up to 2,000 ft. (610 m) with min vent length. See Table 3-3 for derate at
max vent length.
3
Net AHRI Water Ratings shown are based on a piping and pickup allowance of 1.15. The manufacturer should
be consulted before selecting a boiler for installations having unusual piping and pickup requirements, such as
intermittent operation, extensive piping systems, etc.
4
Min DHW flow rate required through boiler to initiate DHW demand. Higher flow rate through fixture may be require
due to mixing at tempering valve and/or fixture itself.
Model
Number
Depth
in. (mm)
Width
in. (mm)
Height
in. (mm)
Space
Heating
Water
sweat, in.
Domestic
Water
sweat, in.
Gas
NPT
Relief
Valve NPT
Maximum
Allowable
Working
Pressure
psig (kPa)
ALTAC-136 16.3 (413) 17.8 (453) 29.8 (757)
1-1/4
3/4
1/2
3/4
50 (345)
ALTAC-200 20.4 (518) 17.8 (453) 29.8 (757)
1-1/4
3/4
1/2
3/4
50 (345)
Table 3-2: Dimensions and Connections
Table 3-1: Ratings
Table 3-3: Air Intake and Vent Lengths
Model Number
Intake/Vent Size in. (mm)
Min Length
ft. (m)
Max Length
ft. (m)
Approx. Derate at
Max. Length (%)
ALTAC-136
Standard
2 (60)
2.5 (0.76)
70 (21.3)
7
w/ increaser
3 (80)
2.5 (0.76)
135 (41.1)
1
ALTAC-200
Standard
2 (60)
2.5 (0.76)
70 (21.3)
9
w/ increaser
3 (80)
2.5 (0.76)
135 (41.1)
5
Table 3-4: Inlet Gas Pressure Range
Min in. wc (kPa)
Max in. wc (kPa)
Natural Gas
2.5 (0.62)
14.0 (3.48)
LP Gas
8.0 (1.99)
