22
XTherm heaters are wired for 120VAC single phase
power. Models 1005 and 1505, except WH 1505 mod-
els equipped with a heater pump for hard water,
require 20A service for the heater and 15A service for
the heater pump or a single 40A rated circuit. Model
1505 heaters equipped for hard water require 15A
service for the heater and 25A service for the heater
pump or a single 50A rated circuit. Model 2005
heaters require 25A service for the heater and 25A
service for the heater pump, or a single 50A service.
Consult the wiring diagram shipped with the heater.
Use appropriately sized wire as defined by NEC, CSA
and/or local codes. All primary wiring should be rated
for 125% of the minimum required service. Before
starting the heater, verify that the correct 120VAC volt-
age is being supplied to the heater and pump.
If any of the original wire supplied with the heater must
be replaced, it must be replaced with 105°C or its
equivalent.
Power is connected to the heater via the rear wiring
box as shown at the top of Fig. 19. Main heater power
is connected to terminals 1, 2 and 3 and pump power
is connected to terminals 4, 5 and 6.
Field wiring connections such as sensors, interlocks,
enable/disable and alarm contacts are made at the low
voltage terminal strip at the front of the heater as
shown at the bottom of Fig. 19.
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.
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 I: Maximum Equivalent Pipe Length
NOTE: Manifold pressures should be ±0.2 in. WC.
Table J: Manifold Gas Pressure Settings
Model No.
1-1/4” NPT
1-1/2” NPT
2” NPT
2-1/2” NPT
N
P
N
P
N
P
N
P
1005A
35
55
35
90
125
300
300
1505A
10
15
15
25
60
150
150
275
2005A
35
90
85
210
Model No.
Manifold Gas Pressure
(High Fire Values)
Natural Gas
Propane Gas
1005A
-4.6
-6.6
1505A
-7.1
-8.0
2005A
-4.2
-9.3