SECTION A: Before Installation
All Raypak heaters are National Board Approved, and
design-certified and tested by the Canadian Standards
Association (CSA) for the U.S. and Canada. Each heater
is constructed in accordance with Section IV of the
American Society of Mechanical Engineers (ASME)
Heater Pressure Vessel Code and bears the ASME stamp.
The heater also complies with the latest edition of
ASHRAE 90.1 Standard.
WARNING: Altering any Raypak pressure vessel by
installing replacement heat exchangers, tube bundle head-
ers, or any ASME parts not manufactured and/or approved
by Raypak will instantly void the ASME and CSA ratings
of the vessel and any Raypak warranty on the vessel. Al-
tering the ASME or CSA ratings of the vessel also
violates national, state, and local approval codes.
Installations at Elevation
Rated inputs are suitable for up to 4,500 ft elevation with-
out de-rating. Consult the factory for installations at
altitudes over 4,500 ft above sea level. No hardware
changes are required to the heaters for installations up to
10,000 ft (adjustments may be required).
Component Locations
Panels omitted for clarity
Fig. 1: Component Locations - Side
Top panel, blower and gas train omitted for clarity
Fig. 2: Component Locations - Top
Fig. 3: Component Locations – Rear
General Information
MBTUH
Water
Model
Input
Conn.
No.
(NPT)
Max. Min.
503
500
125
753
750
188
1003
999
250
2-1/2 1-1/4
1253
1250 312
2-1/2 1-1/4
1503
1500 375
2-1/2 1-1/4
1753
1750 438
2-1/2
2003
1999 500
2-1/2
Table A: Basic Data
4
Gas
Vent Size
Conn.
(in.)
(NPT)
N
P
Flue Intake
2
1
1
6
2
1
1
6
1
6
1
8
1
8
2
1
8
2
1
8
6
6
6
8
8
8
8
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