87%-Efficiency Boilers; Special Instructions - Raypak Hi Delta 992B-1262B Installation & Operating Instructions Manual

87%-Efficiency Boilers –

Special Instructions

NOTE: The constructions of the 84%- (standard)
and 87%-efficiency (optional) boilers are very similar,
and they are installed to the same requirements,
except as noted in this section.
Water Piping
An 87%-efficiency boiler requires a minimum inlet
water temperature of 120ºF (49ºC) to prevent exces-
sive condensation in the combustion chamber. An
87%-efficiency boiler operated with an inlet tempera-
ture of less than 120ºF (49ºC) must have a manual
bypass or an approved low-temperature operation
system to prevent problems with condensation. A man-
ual bypass, shown in Fig. 15, must be piped into the
system at the time of installation. This piping is like a
primary/secondary boiler installation with a bypass in
the secondary boiler piping. Raypak strongly recomm-
20°F T
Model
No.
gpm
992BE 86
1262BE 110
1532BE 132
1802BE N/A
2002BE N/A
2072BE N/A
2342BE N/A
Note: Basis for minimum flow is 40°F ΔT. Basis for maximum flow is 132 gpm.
Combustion
Air Supply
From Inside Building
(Non-Direct Venting)
From Outside Building
(Direct Venting)
Table P: Category Determination for Venting Purpose and Venting Arrangement
30°F T
P (ft) gpm P (ft)
5.6 57 2.5
10.3 73 4.6
16.5 89 7.6
N/A 104 11.5
N/A 116 14.8
N/A 120 15.8
N/A N/A N/A
Table O: Heater Rate of Flow and Pressure Drop
Exhaust
Configuration
Vertical Natural Draft
Venting
Horizontal Through-
the-Wall Venting
Vertical Natural Draft
Venting
Horizontal Through-
the-Wall Venting
ends that a thermometer be placed into the boiler inlet
piping next to the in/out header to facilitate tempera-
ture adjustment. Inlet water temperatures below 120ºF
(49ºC) can excessively cool the products of combus-
tion, resulting in condensation on the heat exchanger.
Venting
CAUTION: Proper installation of flue venting is criti-
cal for the safe and efficient operation of the boiler.
Appliance Categories
See Table P for appliance category requirements for
the 87%-efficiency Hi Delta.
NOTE: For additional information on appliance
categorization, see appropriate code NFGC (U.S.)
and B149 (Canada), or applicable local building
codes.
40°F T Min. Flow
gpm P (ft) gpm
43 1.4 43
55 2.6 55
67 4.3 67
78 6.5 78
87 8.5 87
90 9.1 90
102 12.9 102
Heater Venting
Category
II
Stainless Steel
(Gas Tight)
IV
II
Stainless Steel
(Gas Tight)
IV
45
Max Flow
P (ft) T gpm
1.4 40 132
2.6 40 132
4.3 40 132
6.5 40 132
8.5 40 132
9.1 40 132
12.9 40 132
Certified Combustion Air
Materials Inlet Material
AL29-4C
Galvanized Steel
AL29-4C
PVC
ABS
CPVC
P (ft) T
13.1 13
14.8 17
16.5 20
18.3 24
19.0 26
19.0 27
21.4 31