Sequence Of Operation - Rheem RWI Series Installation Instructions Manual

SEQUENCE OF OPERATION

COOLING
Single Stage Cooling
• When the thermostat calls for cooling
(Y), there is a 1 second delay then
the control energizes the high blower
tap (COOL_HI).
• When the thermostat ends the call for
cooling (Y), there is a 30 second
cooling off delay then the control de-
energizes the high blower tap
(COOL_HI).
• A call for cooling has priority over
continuous fan.
HEATING (HYDRONIC)
• On a call for heating the pump will
start.
• After a sixty second delay the control
will look at the FS jumper if this is
jumpered the control will go into
water heating mode and ignore the
temperature sensors.
• If the air supply temperature is
greater than 85°F the control will
energize the indoor blower. If the air
temperature is less than 85°F the
control will turn off the pump and go
into a 5 minute delay.
• If the supply temperature is adequate
the main blower will then be
energized and run for 30 seconds.
• After the 30 second delay the control
will monitor the supply temperature. If
this drops the control will turn off the
pump and go into a 5 minute delay. If
the temperature is greater than the
shut off temperature the control shall
remain in heating mode.
• There must be a minimum delta of
10°F to remain in the heating mode.
• When the W call ends the pump shall
de-energize the blower shall turn off
after a blower off delay.
The FS input shall be used to allow a
way to bypass the system to allow it to
run. If this is jumpered the control will
ignore the temperature and go into a
heating cycle.
HEATING (Heat pump is the
primary source of heat)
Single Stage Heating
• The thermostat calls for heating (Y,
R, and B), there is a 1 second delay
then the control energizes the high
blower tap (COOL_HI).
• When the thermostat ends the call for
cooling (Y), there is a 30 second
cooling off delay then the control de-
energizes the high blower tap
(COOL_HI).
• When the thermostat calls for
emergency heat (W), the hydronic
heating mode is activated.
BLOWER TIME DELAY (HEATING
OR COOLING)
All models are equipped with a blower
time delay (BTD) in lieu of a blower relay
(BR) (see Figure 19). The blower will run
for 30 seconds after the blower time
delay (BTD) is de-energized.
DEFROST (DEFROST HEAT
CONTROL)
• For sequence of operation of defrost
controls, see outdoor heat pump
installation instructions.
• Supplemental heat during defrost can
be provided by connecting the purple
(PU) pigtail in the outdoor unit to the
W on the thermostat. This will
complete the circuit between R and W
through a set of contacts in the defrost
relay (DR) when the outdoor heat
pump is in defrost. This circuit, if
connected, will help prevent cold air
from being discharged from the indoor
unit during defrost.
• For most economical operation, if cold
air is not of concern during defrost, the
purple wire can be left disconnected.
Supplemental heat will then come on
only when called for by second stage
room thermostat.
EMERGENCY HEAT (HEATING
HEAT PUMP)
• If selector switch on thermostat is set
to the emergency heat positioin, the
heat pump will be locked out of the
heating circuit, and all heating will be
hydronic heat. Jumper should be
placed between W and E on the
thermostat sub-base so that the
electric heat control will transfer to the
first stage heat on the thermostat. This
will allow the indoor blower to cycle on
and off with the electric heat when the
fan switch is in the auto position.
ROOM THERMOSTAT
(ANTICIPATOR SETTING)
See instructions with outdoor section,
condensing unit or heat pump for
recommended room thermostats.
• The thermostat should be mounted
4 to 5 feet above the floor on an
inside wall of the living room or a
hallway that has a good air
circulation from the other rooms
being controlled by the thermostat.
It is essential that there be free air
circulation at the location of the
same average temperature as other
rooms being controlled. Movement
of air should not be obstructed by
furniture, doors, draperies, etc. The
thermostat should not be mounted
where it will be affected by drafts,
hot or cold water pipes or air ducts
in walls, radiant heat from
fireplaces, lamps, the sun, T.V. or
an outside wall. See instructions
sheet packaged with thermostat for
mounting and installation
instructions.
MODULATING HEATING
(HYDRONIC)
On a call for heat, the pump will start.
After a two-minute delay the control
will start monitoring the supply air
temperature sensor.
If the air supply temperature is
greater than 85ºF the control will
energize the indoor blower. If the air
temperature is less than 85ºF the
control will go into a 5-minute delay.
The pump control will then begin to
control the system to try and maintain
a delta between the inlet water
temperature and the supply air
temperature. There is an adjustment
on the pump control 1 to 10. Each
point is a difference of 5 degrees. A
setting of 4 will provide a 20ºF
difference between the air and the
water temperatures.
Example: 120º Water inlet a setting of
4 will provide 100ºF leaving air
temperature.
If the supply air drops below 85ºF for
30 seconds the control will go into a
5-minute delay and restart the heating
cycle if necessary.
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