Weil-McLain Ultra Electric Water Heater - Manual (Page 9)

Part number IWHA016A/1103
9
PLUS Line Instruction Manual Supplement
PLUS & PLUS
WATER HEATERS WITH GAS
-
FIRED WATER BOILERS
Wiring a system circulator
1. For combined systems, to activate a system
circulator when the Boiler circulator operates, wire
as shown at bottom of Figure 7, page 8.
2. You must install a relay as shown. DO NOT wire in
parallel with the Boiler circulator. See CAUTION
in Figure 7.
Routing line voltage wiring
1. Route line voltage connections to the jacket
openings shown in Figure 8.
Low voltage connections (Fig. 9)
1. Connect low voltage wiring to low voltage terminal
strip (Figure 9, item 1) as shown in Figure 9 and
the boiler wiring diagram.
2. Route all low voltage wires through grommeted
jacket opening to right of low voltage terminal strip,
as shown in Figure 8.
Room thermostat (space heating)
1. For combined space heating/water heating systems,
connect Figure 9, item 2, room thermostat or end
switch (isolated contact only) between terminals 5
and 6.
2. Install thermostat on inside wall away from
influences of drafts, hot or cold water pipes, lighting
fixtures, television, sunrays, or fireplaces.
3. Thermostat anticipator (if applicable):
a. If connected directly to boiler, set for 0.1 amps.
b. If connected to relays or other devices, set to match
total electrical power requirements of connected
devices. See device manufacturers’ specifications and
thermostat instructions for details.
Outdoor temperature sensor
1. Outdoor reset operation applies only to combined
space heating/water heating systems.
2. Connect outdoor temperature sensor (Figure 9,
item 6) between terminals 1 and 2 to enable
outdoor reset operation of the Ultra boiler. If fixed-
temperature operation is required, do not install
outdoor sensor.
3. Mount sensor on exterior wall, shielded from direct
sunlight or flow of heat or cooling from other
sources.
4. Install a summer/winter switch (Figure 9, item 7)
across terminals 1 and 2 to force fixed-temperature
operation during summer months. (When the
switch is closed, boiler will attempt to maintain
constant temperature.)
5. Route sensor wires through the grommeted hole
at right of the electrical entrance (see Figure 8).
PLUS water heater thermostat
1. Connect PLUS water heater aquastat terminals “C”
and “1” to Ultra Boiler low voltage terminal strip
between terminals 3 and 4 (Figure 9, item 3).
Additional limits
1. Connect additional limit controls and interlocks
between the terminals shown in Figure 9.
2. Controls connected between terminals 6 and 7 (see
Figure 9, item 4) will cause a soft lockout
(automatic reset). When limit(s) closes, boiler will
resume normal operation.
3. Controls connected between terminals 6 and 8 (see
Figure 9, item 5.) will cause a hard lockout (manual
reset). The boiler will only restart after the Ultra
display panel RESET switch is pressed.
Field wiring
(continued)
3
Figure 8 Routing field wiring