Raypak 2503, Инструкция по установке и эксплуатации

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pump.
Pumps must use a separate power supply and run the
power through a field-supplied contactor. Use appro-
priately-sized wire as defined by NEC, CSA and/or
local codes. All primary wiring should be 125% of min-
imum rating.
If any of the original wire as supplied with the heater
must be replaced, it must be replaced with 105°C wire
or its equivalent.
All high voltage wiring connections to the MVB heater
are made inside the rear wiring box as shown in
Fig. 18. There are three factory supplied pump inter-
lock relays in the rear wiring box to provide an enable
signal via dry contact (5A max) for the Boiler Pump,
System Pump and Indirect DHW Pump as required for
the system depending on the mode selected within the
VERSA IC control system.
Field-Connected Controllers
It is strongly recommended that all individually-pow-
ered control modules and the heater should be
NOTE: Field-supplied isolation relays should be
installed when field-connected controllers are
mounted more than 50 equivalent feet (18 AWG)
from heater. See wiring diagrams.
Electrical Power Connections
Installations must follow these codes:
• National Electrical Code and any other national,
state, provincial or local codes or regulations hav-
ing jurisdiction.
• Safety wiring must be NEC Class 1.
• Heater must be electrically grounded as required
by the NEC.
• In Canada, CSA C22. 1 C.E.C. Part 1.
The MVB heaters are wired for a 240 VAC, single-
phase power supply. Consult the wiring diagram
shipped with the heater. Before starting the heater,
check to ensure proper voltage to the heater and
Natural Gas – 1,000 BTU/ft
3
, 0.60 specific gravity at 0.5 in. •
WC pressure drop
Propane Gas – 2,500 BTU/ft
3
, 1.53 specific gravity at 0.6 in. •
WC pressure drop
Table H: Maximum Equivalent Pipe Length
NOTE: Manifold pressures should be ±0.2 in. WC.
Table I: Manifold Gas Pressure Settings
Fig. 19: Wiring Electrical Connections
NOTE: Minimum 18 AWG, 105°C, stranded wire
must be used for all low voltage (less than 30 volts)
external connections to the unit. Solid conductors
should not be used because they can cause
excessive tension on contact points. Install conduit
as appropriate. All high voltage wires must be the
same size (105°C, stranded wire) as the ones on the
unit or larger.
Model
No.
2-1/2 in. NPT 3 in. NPT 4 in. NPT
N P N P N P
2503 55 135 160 400 600 --
3003 40 85 120 250 500 --
3503 30 45 80 200 400 600
4003 25 35 65 160 300 400
CAUTION: For proper operation, no more than a
30% drop in gas supply pressure from no-load to full-
load conditions is acceptable. Under no
circumstances should the pressure be outside the
listed operational range.
Model
No.
Manifold Gas Pressure
(High Fire Values)
Natural Gas Propane Gas
2503 -4.8 -6.4
3003 -6.7 -8.8
3503 -6.8 -9.5
4003 -4.7 -7.4