Rinnai Energysaver EX38C User manual

Energysaver ®
Gas Direct Vent Wall Furnace
—Do not store or use gasoline or other ammable vapors and liquids in the vicinity of this or any other
appliance.
—WHAT TO DO IF YOU SMELL GAS
 Do not try to light any appliance.
 Do not touch any electrical switch; do not use any phone in your building.
 Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instrucons.
 If you cannot reach your gas supplier, call the re department.
—Installaon and service must be performed by a licensed professional.
If the informaon in these instrucons is not followed exactly, a re or explosion
may result causing property damage, personal injury or death.
WARNING
READ ALL OF THE INSTRUCTIONS THOROUGHLY BEFORE INSTALLING OR OPERATING
THIS HEATER.
This manual provides information on the installation, operation, and maintenance of the heater. For
proper operation and safety, it is important to follow the instructions and adhere to the safety
precautions.
A licensed professional must install the fan convection heater according to the exact instructions
within this manual.
The consumer must read the entire manual to properly operate the heater and to have regular
maintenance performed.
EX38C.................(RHFE-1005FTA)
Installer: Leave this manual with the appliance.
Consumer: Retain this manual for future reference.
This appliance may be installed in an aftermarket, permanently located, manufactured (mobile)
home, where not prohibited by local codes.
Register your product at www.rinnairegistration.com or call 1-866-RINNAI1 (746-6241)

2Rinnai Corporation EX38C Manual
This appliance may be installed in an aftermarket, permanently located, manufactured home
(USA only) or mobile home, where not prohibited by local codes.
This appliance is only for use with the type of gas indicated on the rating plate. This appliance
is not convertible for use with other gases, unless a certified kit is used.
Table of Contents
This appliance may be installed as an OEM installation in a manufactured home (USA only) or
mobile home and must be installed in accordance with the manufacturer’s instructions and the
Manufactured Home construction and Safety Standard, Title 24 CFR, Part 3280, in the United
States, or the Mobile Home Standard, CAN/CSA Z240 MH Series, in Canada.
Consumer Safety Information
Safety Definitions .............................................3
Safety Behaviors and Practices .......................3
Safety Features................................................4
Specifications
Appliance Specifications ..............................4, 5
Features ...........................................................5
Flue Manifolds..................................................5
Operating Instructions
Getting to Know your New Heating Appliance 6
Control Panel ...................................................7
On / Off.............................................................7
Child Lock ........................................................7
Setting the Clock ..............................................8
Operating the Heater Manually ........................8
Setting and Operating the Timers ....................8
Override Function.............................................9
Economy (Energy Saving Mode) .....................9
Set Back .........................................................10
Humidifier and Air Flow Direction...................10
Care and Maintenance...................................11
Before Making a Service Call.........................12
Fault Codes....................................................13
Restart Function.............................................14
Troubleshooting .............................................14
Installation Instructions
General Instructions....................................... 15
Gas Connection .............................................16
Clearances to Combustibles..........................16
Flue Terminal Clearances........................17, 18
Dimensions ....................................................19
Installation Parts ...........................................20
Drilling Flue Hole ...........................................21
Attach Wall Brackets...................................... 21
Attach Back Spacers ..................................... 21
Flue Manifold Installation .........................22, 23
Extension Kit Installation...........................24-26
Connecting the Appliance..............................27
Adjust Gas Pressure Settings..................28, 29
Operating Instructions.................................... 30
Cut-Away Diagram.........................................31
Wiring Diagram .............................................. 32
Ladder Diagram ............................................. 33
Parts List ...................................................34-41
Consumer Support
Warranty Information .....................................42
Limited Warranty......................................42, 43
State Regulations..............................................44

Rinnai Corporation EX38C Manual 3
WARNING
CAUTION
Safety Behavior and Practices
 Do not block the warm air discharge. Do not allow
anyone to sleep directly in front of the appliance.
 Due to high temperatures, the appliance should be
located out of traffic and away from furniture and
draperies.
 Children and adults should be alerted to the hazards
of high surface temperature and should stay away
to avoid burns or clothing ignition.
 Young children should be carefully supervised when
they are in the same room as the appliance.
 Clothing or other flammable material should not be
placed on or near the appliance.
 Any safety screen or guard removed for servicing
must be replaced prior to operating the appliance.
 Do not insert items into the louvers.
 Do not spray aerosols near the appliance while it is
operating. Most aerosols contain butane gas which
is flammable.
 Do not unplug the appliance while it is operating or
while the fans are on.
 Do not use bare hands to touch the front louvers
due to high temperatures which may cause burns.
 Wear hand protection when touching the side back
covers, front louver, and rear intake for the
convection fan.
 Prevent dust from accumulating on the power cord,
side covers, and parts behind the appliance.
 Do not sit on the heater.
 Do not place containers of liquid on top of the
heater. Water spillage can cause extensive
damage to the appliance and may result in electric
shock.
 Repairs should be performed by a qualified service
technician.
 Keep the area around the appliance clear and free
from combustible materials, gasoline, and other
flammable vapors and liquids.
 Never store liquid propane containers indoors.
 Do not use this appliance if any part has been under
water. Immediately call a qualified service
technician to inspect the appliance and to replace
any part of the control system and any gas control
which has been under water.
 This appliance is equipped with a three-prong plug
for your protection against shock hazard and should
be plugged directly into a properly grounded three-
prong receptacle. Do not cut or remove the ground
prong from this plug.
 Any alteration to the appliance or its controls can be
dangerous.
 Do not operate appliance with the panels removed,
cracked or broken. Replacement of the panels
should be done by a licensed or qualified service
person.
Consumer Safety Information
Safety Definitions
This is the safety alert symbol. This symbol alerts you to potential hazards that can kill or hurt you and
others.
Indicates an imminently hazardous situation which, if not avoided, will result in death or
serious injury.
Indicates a potentially hazardous situation which, if not avoided, could result in death or
serious injury.
Indicates a potentially hazardous situation which, if not avoided, could result in minor or
moderate injury. It may also be used to alert against unsafe practices.
DANGER
CAUTION
WARNING

4Rinnai Corporation EX38C Manual
Application For manufactured home (USA only) or mobile home or residential installation
convertible for use with natural gas and liquefied petroleum gases (propane /
LPG) when provision is made for the simple conversion from one gas to the
other.
For commercial setting.
For installation at altitudes up to 10,200 feet (3109 m).
General Description Forced combustion, forced convection, flued gas furnace
Operation Push button electronic
Gas Connection 1/2 in NPT
Gas Control Electronic
Burners Stainless steel Bunsen burner
Temperature Control Electronic thermostat
Ignition System Electronic spark ignition
Flue System The flue must be terminated to atmosphere with only flue components listed
with the appliance’s certification. Warranty will be voided if non listed
components are installed.
Humidifier Tray Capacity - 6.3 pints (3000 cc)
Electrical Connection AC 120V, 60 Hz, 117 watts
Weight 88 lbs (40 kg)
Noise Level 39 - 46dB
Specifications
Rinnai is continually updating and improving products. Therefore, specifications are subject to change without
prior notice.
The efficiency rating of this appliance is a product thermal efficiency rating determined under continuous operating
conditions and was determined independently of any installed system.
Safety Features
 Overheat: The appliance will automatically shut
down when the appliance exceeds a predetermined
temperature.
 Flame Failure: The appliance will automatically
shut down if the burner flame is extinguished.
 Power Failure: The appliance will cut off the gas if
it loses electrical power.
 Power Surge Fuse: A glass fuse on the PC board
protects against overcurrent. If the fuse blows then
all indicator lamps will be off.
 Spark Detector: The appliance automatically shuts
down if there is an abnormal spark at ignition.
 Fusible Link: In case the overheat feature
prevents the temperature from rising then the fusible
link will break shutting off the appliance.
Appliance Specifications

Rinnai Corporation EX38C Manual 5
Features
Appliance Specifications
The following flue manifold sizes are
available for different wall thicknesses: Name Kit No. fits walls
S Vent Kit FOT-150 3 - 4 1/2 in (75 - 115 mm)
A Vent Kit FOT-151 4 1/2 - 9 1/2 in (115 - 240 mm)
B Vent Kit FOT-152 9 1/2 - 15 3/4 in (240 - 400mm)
C Vent Kit FOT-153 15 3/4 - 23 5/8 in (400 - 600 mm)
D Vent Kit FOT-154 23 5/8 - 31 1/2 in (600 - 800 mm)
Natural Gas Propane Gas
Minimum supply gas pressure 3.5 in (89 mm) W.C. 8.0 in (203 mm) W.C.
Maximum supply gas pressure 10.5 in (267 mm) W.C. 13.0 in (330 mm) W.C.
BTU/hour input Low 13,200 High 38,400 Low 13,200 High 36,500
BTU/hour output Low 10,560 High 30,720 Low 10,560 High 29,200
Flue Manifolds
 Restarts automatically when ignition or combustion
fails.
 Clean Heating Forced Flue Type
 Easy Operation One-Touch Ignition
 Sensible Temperature Control Feature
 Programmable Thermostat
 Warm Air Outlet at Floor Level (keeps your feet
warm)
 Child Lock
 Room Temperature Setting Memory
 Clean the Air Filter - Indicator Lamp
 Energy Saving Economy Setting
 Humidifier Tray
 Air Flow Directional Louvers
 Direct Vent Easily Installed
 Proportional Heating Variable Capacity
 Hush! Quiet Operation
 Modern Design Minimizes Floor Space
Requirements
 Dimmer
 Fault Code Message Display
 Temperature Settings in Fahrenheit or Celsius
 Temperature Setting in Timer Operation
 Timers 1 and 2
 Set back (setting a minimum temperature)
 1F°(1C°) increments
Vent A Kit is included with
the appliance.

6Rinnai Corporation EX38C Manual
Getting to know your New Heating Appliance
Operating Instructions
GAS CONNECTION
1/2” NPT
PLASTIC TIE
FOR AIR INLET
POWER CORD
PLUG 120V AC
AIR FILTER
VENT TERMINAL
COMBUSTION /
EXHAUST
EXHAUST PIPE
COMBUSTION AIR
INTAKE HOSE
AIR FILTER
PIPE STOPPER
THERMISTOR
BENT ELBOW
WARM AIR OUTLET
HUMIDIFIER
OPEN THE DOOR
AND POUR WATER
INTO THE TRAY
CONTROL PANEL
OPERATION /
TEMPERATURE
CONTROL DISPLAY
FILTER LAMP
OPERATION LAMP
RATING PLATE
MODEL NUMBER,
SERIAL NUMBER,
GAST TYPE, ETC.

Rinnai Corporation EX38C Manual 7
Control Panel Control Panel
Sensible Temperature Control
Child Lock
The Child Lock will help to prevent accidental operation of the appliance and to
prevent children from operating the appliance.
To activate Child Lock, press the Child Lock button. The indicator will light and a beep
will sound.
To deactivate the Child Lock, press the Child Lock button and hold for about 2
seconds. The indicator light will go out and a beep will sound.
 The lock can be activated when the heater is ON or OFF.
 If activated while the heater is ON, all controls other than the OFF switch will be
locked.
 If activated while the heater is OFF, then all controls will be locked.
 If the heater is turned off while the Child Lock is activated, it cannot be turned on
again until the lock is deactivated.
 Deactivating the lock releases the control buttons.
The sensible temperature control feature allows
comfortable heating which matches the conditions in
the room.
Based on the information collected by the room
temperature thermistor when the heating starts, the
heating capacity is automatically adjusted to achieve a
comfortable heating effect and to reach the
temperature setting quickly.
Occasionally, the room temperature may briefly exceed
the temperature setting due to the layout of the room or
heating area.
On / Off
Press the ON/OFF button to operate the heater. The ON indicator will glow green.
Once the burner ignites, the ON indicator will glow red. When the heater warms up,
the convection fan will automatically start.
To turn the heater off, press the ON/OFF button. The ON indicator light will go out. The
fan will continue to operate for several minutes after the burner has gone out in order
to cool the heater. Do no unplug the heater while the fan is running.
Display
After the heater is turned on and begins operating, the display will dim. The display will turn off when the heater is
turned off. While programming the timers the display will turn off for several seconds after a button is last pushed.
Fahrenheit or Celsius (Factory default is °F)
1. The heater must be turned off.
2. Press the Timer 1 and Timer 2 button at the same time for about 5 seconds. The display will show “°C” or “°F”.
3. Use the arrow keys to select the temperature scale.
4. Press the ON/OFF button.

8Rinnai Corporation EX38C Manual
Operating the Heater Manually
Setting the Clock
1. Press the “Program” button.
2. The light next to “Clock” should be flashing. Press
the up and down arrows to set the time. Holding
down either of the arrow keys will change the time
more quickly.
3. Press the “Program” button until none of the time
options are flashing up.
Setting and Operating the Timers
Confirm the clock is correct.
NOTE: The clock will have to
be reset in case of a power
failure. However the timers will
retain their settings.
The heater will start before the
programmed starting time in
order to heat the room by the
programmed starting time.
The timers can be set while the
heater is on or off. To operate
the timer, the heater must be
on.
Setting the timers:
1. Press the “Program” button twice to set Timer 1.
2. The light next to “Timer 1 on” should be flashing.
Press the up or down arrows to set the start time.
Holding down either of the arrow keys will change
the time more quickly.
3. Press the “Program” button again so that the
Timer 1 off position is flashing. Press the up or
down arrows to set the end time. Holding down
either of the arrow keys will change the time more
quickly.
4. Press the “Program” button again so that the
Timer 1 Temp Position is flashing. Press the up or
down arrows to set the temperature.
5. Press the “Program” button again to set the times
for Timer 2. Follow the same steps above to set
the start and end times.
6. Press the “Program” button until none of the time
options are flashing up.
Operating the timers:
To operate the heater using a Timer, press the ON/
OFF button and the appropriate Timer button. The
heater will operate from the start to end times you
have entered for that Timer. It will operate at the
temperature setting that has been set for the heater.
The timer can be set while the heater is operating.
1. Turn the heater on by pressing the “ON/OFF”
button.
2. Press the up or down arrows to set the
temperature. The left display shows the
temperature setting. The right display shows the
room temperature.
The thermostat automatically modulates the burner
and the fan to maintain the temperature setting.
The temperature settings available are:
 LO - burner is on minimum combustion
 60° F - 80° F in one degree increments
 HI - burner is on maximum combustion
While in standby, the timer LED will be on with a solid
light. When operating the LED will be flashing.

Rinnai Corporation EX38C Manual 9
Override Function
This function is used only when the
heater is in Timer operation.
It allows you to “override” the reset timer
setting until the beginning of the next
Timer period.
For example, if the heater is ON,
pressing the “Override” button will turn
the heater OFF until the next period. If
the heater is OFF, pressing the “Override” button will
turn the heater ON, and allow you to select a
temperature setting, until the next period. The heater
will remain on until the next timer period or until the
Override function is turned off.
When in override function, pressing the “Override”
button will return the heater to the operation of the
current timer period.
Economy (Energy Saving Mode)
The Economy mode can only be set
while the heater is operating (heating).
Once it is set, it will remain in the system
memory until deactivated.
1. To turn the Economy mode on, press
the “Economy” button. The Economy
indicator is lit.
 The Economy mode now remains
in the system memory.
 If the appliance is turned off manually, or stops
heating as a result of an OFF timer period, the
“Economy “ indicator will go out.
 Whenever the appliance starts heating again,
the “Economy” indicator will light.
2. To turn the Economy mode off, press the
“Economy” button. The “Economy “ indicator will
go out.
 The Economy mode can only be turned off while
the heater is operating (heating) and when the
“Economy” indicator is lit.
Economy Mode Information
After the room is heated initially, the air temperature
may be dropped to a lower level without affecting
comfort. The Economy Mode reduces the
temperature by 2 ºF, 30 minutes after the room
temperature setting is reached. After another 30
minutes, it reduces the temperature setting by another
2 ºF, effectively saving energy. The room temperature
setting will drop up to a total of 4 ºF.
The Economy Mode will not operate if the heater is
under capacity for the room size.

10 Rinnai Corporation EX38C Manual
Humidifier and Air Flow Direction
Adjusting Air Flow Direction
The vertical louvers may be adjusted to move the air
flow more to the right or to the left.
Use a screw driver or similar object to bend each
louver to the desired position.
Do not bend repeatedly (no more than 5 times) or else
the louver will break.
The horizontal louvers (which determines the vertical
air flow direction) are fixed and cannot be adjusted.
CAUTION
Do not adjust the air flow
louvers while warm air is
flowing.
Adding Water to the Humidifier
Set Back
This function allows a minimum room temperature to be pre-set, between 38ºF
and 78ºF (in 1ºF increments). This temperature should be set below the room
temperature setting. The default setting is 60ºF. Once the Set back function is
selected the appliance will start heating whenever the room temperature falls
below the selected temperature, regardless of timer or manual settings.
Follow these steps to set and operate the Set back feature:
1. Make sure the heater is turned OFF.
2. Press the “Set back” button. The light above the button will come on.
3. Press the up and down buttons to set the minimum temperature.
When the “Set back” indicator is on, frost protection is operating, and will always
prevent the room temperature from falling below the pre-set minimum
temperature (as long as electric power and gas is supplied).
To turn this feature off, press the “Set back” button.
The unit will retain its ON or OFF setting after a power failure. (Set Back feature
is on by factory default.)
Access Door
Max. Fill Line
Humidifier Tray
Filler Spout
Do not force door open too far.
Close door during operation.
Pull
To fill the tray, open the door as shown in the diagram
and pour water into the tray using the spout built into
the door. The air will be humidified as it passes over
the water in the tray.
During operation a small amount of condensation is
produced in the flue system and drains into the
humidifier tray.
If the water overflows from the water level hole, then
do not add any more water.
CAUTION
Do not fill the tray while the
appliance is in operation.
Close the door after filling.
The humidifier tray and
surrounding area are hot
when the appliance is on.