RX Heat RX-TM-0809 User manual

RX12
DIRECT GAS-FIRED
CONSTRUCTION HEATER
TECHNICAL MANUAL
mWARNING:
Fire, burn, inhalation, and explosion
hazard. Keep solid combustibles, such as
building materials, paper, or cardboard,
a safe distance away from the heater as
recommended by the instructions. Never
use the heater in spaces which do or may
contain volatile or airborne combustibles,
or products such as gasoline, solvents,
paint thinner, dust particles or unknown
chemicals.
FOR YOUR SAFETY:
The use and storage of gasoline or other flammable vapors and liquids in open containers in the
vicinity of this appliance is hazardous.
RX-TM-0809
RX12
08/10/09
®
This heater is designed and approved for use as a construction



m
Failure to comply with the precautions and
instructions provided with this heater can
result in death, serious bodily injury and
property loss or damage from hazards of
fire, explosion, burn, asphyxiation, carbon
monoxide poisoning, and / or electrical
shock.
Only persons who can understand and fol-
low the instructions should use or service this
heater.
If you need assistance or heater information
such as an instruction manual, label, etc.
contact the manufacturer. mWARNING:
Not for home or recreational vehicle use.
Made in the USA
HeatTM


Cambridge Engineering, Inc. (“Manufacturer”) warrants its products (“the Products”) to be free from defects in
material and workmanship. Manufacturer’s Rx-Series Products shall be warranted for a period of 12 months from the
date of shipment, except that burner assemblies are warranted for five years from date of shipment.
Buyer’s sole and exclusive remedy for any nonconformity with this warranty shall be, at Manufacturer’s
option, repair or replacement of nonconforming parts, provided that Buyer shall return to Manufacturer, shipping pre-
paid, said non-conforming part(s) bearing a durable tag indicating the Serial Number of the Product from
which the part was taken. In addition, Manufacturer may opt not to repair or replace nonconforming Product
or part(s), but instead may refund to Buyer the price thereof, in lieu of repair or replacement. In no event shall
Manufacturer be liable for more than a refund of the purchase price or replacement value of the Product or
part(s), whichever is less. This Warranty does not apply to field labor charges.
This Warranty does not apply and shall be void as to any Products that are misused or misapplied, that are
installed, operated or maintained not in conformity with Manufacturer’s design, specifications, instructions, or
Technical Manual, or are installed, operated or maintained in violation of any applicable national or local codes
or industry standards.
Manufacturer does not warrant Products, if they are abused, improperly operated or maintained, subjected to
abnormal wear and tear, damaged due to improper gas or electric service, damaged in transit, or that have been
repaired or modified by others without Manufacturer’s written authorization.
Buyer shall have no right to enforce this Warranty unless it has complied with all of its obligations under the
contract for purchase/lease of the Products, including without limitation, being current on all payment terms.
THIS LIMITED WARRANTY IS MANUFACTURER’S ONLY WARRANTY WITH RESPECT TO THE
PRODUCTS, AND IT IS IN LIEU OF AND SUPERSEDES ANY AND ALL OTHER WARRANTIES OF
ANY KIND WHATSOEVER, WHETHER WRITTEN, ORAL OR IMPLIED, INCLUDING WITHOUT
LIMITATION ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE. THE REMEDIES AFFORDED BUYER BY THIS WARRANTY ARE THE ONLY REMEDIES
AFFORDED BUYER FOR ANY NONCONFORMITY WITH THIS WARRANTY OR FOR ANY
DEFECT IN PRODUCTS, SERVICES, OR REPRESENTATIONS PROVIDED BY MANUFACTURER
IN CONNECTION WITH SUCH PRODUCTS. IN NO EVENT SHALL MANUFACTURER BEAR
ANY LIABILITY FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND WHATSOEVER,
INCLUDING WITHOUT LIMITATION PERSONAL INJURY (INCLUDING DEATH), PROPERTY
DAMAGE, LOST PROFITS OR OTHER ECONOMIC LOSS.
Buyer acknowledges that the foregoing warranty, limitations, and exclusions are a reasonable allocation of
commercial risks by and among sophisticated business entities and are not subject to dispute as to their com-
mercial reasonableness, fairness or ability to satisfy the essential purposes of the parties’ transaction.
RxHeat, LLC, has a continuous product improvement program; it reserves the right to change design and speci-
fications without notice.
RxHeat, LLC
760 Long Road Crossing Dr.
Chesterfield, MO 63005
Phone: [phone], Fax: [phone]
www.RxHeat.com
Copyright 2009
All Rights Reserved

Rx-Series



Page
Hazard Summary ....................................................... 2
Typical System Description............................................... 3
Component Identification ................................................ 4
Accessory Options ...................................................... 5
Usage Instructions ................................................... 6-10
Wiring Diagram ....................................................... 11
Supply Pressure Requirements ........................................... 12
Gas Train Components ................................................. 12
Electrical Components.................................................. 13
Component Parts List .................................................. 14
Replacements Parts & Service............................................ 15
Maintenance Instructions..............................................15-18
Disassembled View of ASCO Valve....................................... 19
Troubleshooting Guide ...............................................20-24
Minimum Fire Adjustment Procedure...................................... 25
Maintenance Log ...................................................... 26
RxHeat, LLC
760 Long Road Crossing Dr.
Chesterfield, MO 63005
Phone: [phone], Fax: [phone]
www.RxHeat.com
Copyright 2009
All Rights Reserved
Index

RxHeat, LLC 2 RX-Series Technical Manual


Warnings and Cautions appear at appropriate sections throughout this manual. Read these carefully.
mWARNING: Indicates a potentially hazardous situation which could result in
death or serious injury.
m Indicates a potentially hazardous situation which may result in
minor or moderate injury. It may also be used to alert against
unsafe practices.
 Indicates a situation that may result in accidents with equipment or
property damage only.
The following safety precautions apply to the operation and maintenance of the equipment described by this
technical manual.
mWARNING:
Any unauthorized modification of this equipment shall void warranty.
mWARNING:
Operation, service, and repair of this equipment could result in exposure to electrical,
mechanical or other potential safety hazards and should only be performed by qualified personnel.
Use extreme caution and observe safety regulations at all times.
mWARNING:
Recirculation of room air is not permitted.

can lead to carbon monoxide poisoning, leading to serious injury or death. Symptoms of
carbon monoxide poisoning can include headaches, dizziness and difficulty breathing.
mWARNING:
All factory provided lifting lugs must be used when lifting any unit. Failure to comply with this
safety precaution could result in property damage, serious injury or death.

RX-Series Technical Manual 3 RxHeat, LLC
This heater is designed for outdoor use only. It is intended for use in providing portable, temporary heat to buildings under
construction, alteration or repair. Adequate ventilation must be provided while heater is operating. Combustible solids, such
as building materials, paper or cardboard must be kept a minimum of 6 inches from the sides and top of the heaters, 0 inch-
es from the bottom. Never use this heater in spaces which do or may contain volatile or airborne combustibles, or products
such as gasoline, solvents, paint thinner, dust particles or unknown chemicals.
Adequate building relief shall be provided so as to not over pressurize the building when this heater is operating at its
rated capacity. It should be noted that this can be accomplished by taking into account, through standard engineer-
ing methods, the structure’s designed infiltration rate, by providing properly sized relief openings, by interlocking a
powered exhaust system or by a combination of these methods.



These instructions must be retained for future reference.

The RxHeat™Heater, with high temperature rise Blow-Thru®Technology, includes a control system that is designed
to electronically modulate the gas flow using an amplifier, discharge temperature sensor and heat adjustment dial.
The discharge temperature sensor, which is mounted in the heater’s discharge air stream, transmits a resistance sig-
nal back to the amplifier that corresponds to the discharge temperature. The amplifier creates a voltage output to
drive an electronic proportioning gas valve to maintain the pre-selected temperature that is set on the heat discharge
temperature selector dial.
The RxHeat™Heater is provided with a variable frequency drive (VFD) to allow for variable air
volume between 2400 and 4000 CFM. The VFD air volume control is located in the operator interface panel.
The VFD also limits the fan motor inrush current, allowing the heater to be powered by a generator.

 
The EDL temperature control system utilizes a discharge temperature sensor, which is mounted at the unit’s dis-
charge, to transmit a signal back to the amplifier that corresponds to the discharge temperature. This permits the
adjustment of the discharge air temperature (120°F to 170°F) from the heater’s operator interface panel.
 
The Electronic Discharge w/ Space Modulation temperature control has two modes of operation. The first mode
permits the adjustment of the discharge air temperature from the heater’s operator interface panel as described above.
The second mode utilizes a Remote Space Sensor (RSS), located in the heated space, which transmits a signal to
the amplifier to maintain the user-defined space temperature. The RSS allows the heater to modulate between pro-
grammed MAX and MIN temperatures, factory preset to 210˚F and 40˚F respectively. The space temperature is
field adjustable between 60˚F and 140˚F.

RxHeat, LLC 4 RX-Series Technical Manual

Unit shown with Accessory Options
Rain Hood
Lifting Lug
Disconnect
Connections
Interface
Interface
Operator
Connection
LP Gas Inlet
Heater Unit
Air Deflector
Electrical
Collapsible
(Optional)
Forklift Pockets
Operator
Interface
Panel
(Not shown)
Disconnect
Switch

RX-Series Technical Manual 5 RxHeat, LLC

 Factory installed
option. Includes turning vanes.
Attaches to the discharge of the
unit.
 Factory or field
installed. When combined with
the Caster Set provides on-site
mobility.

For use in EDSM mode. RSS
should be mounted in the heated
space, where it modulates the
heater's discharge temperature
to maintain a user defined space
temperature. RSS attaches to
the heater at the interface on the
Operator Control door and is sup-
plied with a plug and 75' of cord.
OT Remote:
Operating Thermostat for use
in EDL mode. The OT should
be located in the heated space,
where it acts to turn the heat ON
and OFF to maintain user defined
space temperature. In order
to utilize the OT, the Blower
Service Switch must be put in the
"REMOTE" position.

Optional Air Deflector attach-
ments used to easily connect flex-
ible duct for distribution of air
into the building.
 Factory
installed option with integral bird
screen.
 Provides on-site
mobility without the use of heavy
machinery.

RxHeat, LLC 6 RX-Series Technical Manual

mWARNING:
These usage instructions must be followed each time heater is put into service.
mWARNING:
For safety, this heater is equipped with a manual reset high limit
switch, an air-proving switch and redundant electric shut-off valves.
Never operate the heater with any safety device that has been bypassed.


A. Check for any physical damage from shipping or installation that could render heater unsafe or inoperable.
B. Locate heater on level ground in close proximity to the target area and engage the optional caster wheel
brakes located on the wagon’s rear wheels.
m:

C. If applicable, open the heater’s rain hood assembly per the figure below.
D. Install the optional 12" diameter round flexible duct to the optional 12" discharge adaptors and then attach the adap-
tor to the optional air deflector, if applicable. Using the provided worm gear clamps, appropriately secure the duct to
the unit's discharge.

RX-Series Technical Manual 7 RxHeat, LLC
mWARNING:


explosions, personal injury or death. To ensure proper operation and prevent damage
to the unit and bodily injury the following instructions must be followed.


For a heater for connection to natural gas, the installation shall conform with local codes or,






mWARNING:

A. Ensure the manual shut-off valve on the heater’s external gas train is
closed. Verify the unions in the gas piping are tight.
B. A minimum of four (4) 100 lb LP cylinders manifolded together, or one (1)
250 gallon LP tank is required to operate heater. Supply cylinders must be
designed, fabricated, tested and marked in accordance with regulations of the
U.S. Department of Transportation, Canadian Transport Commission or the
Interstate Commerce Commission, and must be arranged to provide for vapor
withdrawal from the operating cylinder(s).


below which they may not allow the heater to operate at rated capacity.
C. LP cylinders must have a pressure regulator rated for at least 1,500,000 Btu/hr at 2 psi to 10 psi
outlet pressure (located downstream of the last cylinder if multiple cylinders are manifolded together).
A 1” female NPT quick disconnect fitting shall be located downstream of the supply cylinder assembly
pressure regulator(s).
mWARNING:


mWARNING:
The hose assembly must be visually inspected prior to each use of the heater. If it is evident there is exces-
sive abrasion or wear, or the hose is cut, it must be replaced prior to the heater being put into operation. The

POL Fittings First Stage
Regulator
Hand Shut-off
Valve
Female Quick
Disconnect
Fitting
Supply Cylinders
Typical LP Supply Cylinder Assembly
Pigtails

RxHeat, LLC 8 RX-Series Technical Manual
D. Connect the gas hose assembly provided with the heater between the LP cylinder(s) and the gas
train.
E. Turn the unit’s “Disconnect Switch” to the “OFF” position. Open the access and control panel doors by
using a flat head screwdriver to turn the access door lock counterclockwise until the latch has disengaged.
Pull open the control panel door and disengage the access panel door latches, located on the inside top and
bottom of the door.
F. Slowly open gas supply valve(s) to allow pressure in manifold assembly to equalize.
mWARNING:
  
  
  
  
G. Check all connections for gas leaks using approved gas leak detectors. Gas leak testing is performed
as follows:
• Check all pipe connections, hose connections, fittings and adapters upstream of the gas supply inlet
connection with approved gas leak detectors.
• In the event a gas leak is detected, check the components involved for cleanliness and proper appli-
cation of pipe compound before further tightening.
• Further tighten the gas connections as necessary to stop the leak.
• Close the access and control panel doors and lock (reverse procedure from item E above)
• Close the external manual shut off valve.
• After all connections are checked and all leaks are stopped, proceed to next step.
 mWARNING:

diagrams to make sure you have a thorough understanding of what is required.
mWARNING:

and should be plugged directly into a properly grounded three-prong receptacle.
A. Check the heater nameplate to determine the voltage and amperage requirements. -
plate voltage may impact heater performance or cause damage to the heater.
B. Install the supply wiring, adequate Branch Circuit Protection and electric grounding in compliance with
the National Electric Code ANSI/NFPA 70 or the Canadian Electrical Code C22.1, Part I.
m


RX-Series Technical Manual 9 RxHeat, LLC

A. Verify that the field wiring, both primary and control, has been installed according to the RxHeat wiring
diagram, National Electrical Code and local electrical codes.
B. Ensure that the rain hood is locked open and the discharge accessories are securely attached. If applicable,
engage the caster brakes and stop blocks.
C. Switch the voltage selector switch (see p. 13) to either 208V or 240V depending on the field wired voltage.
D. Turn the unit’s Disconnect Switch to the “ON” position.
mWARNING:
When disconnect switch is activated with the access doors open, live power is present.
Only experienced technicians with knowledge and respect for live power should proceed beyond this point.
E. Adjust airflow to desired level using the Air Volume Control dial. When using ducting, ensure that bends
are kept to a minimum.
F. Turn the RxSmart™ Selector switch to the “LOCAL” position.
G. Turn the Blower Operating Switch to the “ON” position. The VFD will energize and the blower speed will
slowly increase until operational speed is achieved.
H. Open the external manual shut-off valve located in the heater’s gas train.
I. Turn the Burner ON-OFF operating switch (located on the Control Door) to the “ON” position. The ignition
sequence will begin and the burner “ON” light will energize.

It is normal for air to be trapped in gas hose on new installations. The heater may require
more than one trial for ignition before air is finally purged from line and ignition takes place.


-


J. With the burner operating, spray the complete gas train and supply piping with leak detector solution,
checking all pipe connections and plugs.
mWARNING:
All gas leaks detected must be repaired before heater is placed into service.
K. Adjust the temperature to the desired level using the Temperature Select Dial. Adjust the blower speed to
the desired airflow level using the Air Volume Control.
L. Turn the Burner “ON-OFF” switch to the “OFF” position.
M. Turn the unit’s Disconnect Switch to the “OFF” position.

RxHeat, LLC 10 RX-Series Technical Manual
N. Using the “Local/Remote” Mode RxSmart™ Switch located on the Operator Interface Panel (see pg. 13),
select the unit’s control system mode.
O. When utilizing the “REMOTE” control system, connect the RSS to the RSS Interface using the Remote
Space Sensor male connector.
P. Select the desired room temperature using the “Up” and “Down” arrows on the Remote Space Stat.
Q. Close and secure the Access and Control Panel Doors.
R. To restart unit for normal operation, turn unit’s Disconnect Switch to the “ON” position.
S. Turn the Burner “ON-OFF” switch to the “ON” position.

A. Close the LP supply cylinder valve(s). The gas must be turned off at the LP supply cylinder(s) when the
heater is not in use.
B. Allow the heater to burn off any fuel gas remaining in the gas supply line. Turn the the Burner ON- OFF
switch to the “OFF” position. Close the manual shut-off valve on the heater’s external gas train.
C. Turn the heater Disconnect switch to the “OFF” position.
D. Disconnect the electric supply. Disconnect the gas supply piping from the heater’s external connection.
Seal all gas supply inlets to prevent the entry of debris.
E. Remove any attached flexible duct. Close the rain hood assembly (if used).
F. When the heater is stored indoors, the connection between the propane supply cylinder(s) and the heater
must be disconnected and the cylinder(s) removed from the heater and stored in accordance with the
Standard for the Storage and Handling of Liquefied Petroleum Gases, ANSI/NFPA 58 and the Natural Gas
and Propane Installation Code, CSA B149.1.
mWARNING:
The gas supply hose assembly shall be protected from traffic, building materials and
contact with hot surfaces both during use and while in storage.

RX-Series Technical Manual 11 RxHeat, LLC


AF Air Flow Switch
AMP Amplifier Solid State
AVC Air Volume Control
BOS Burner ON-OFF Switch
CR1 Control Relay - Gas Valve On
CR2 Control Relay - Gas Valve On
CR3 Control Relay - Call for Blower
CR4 Control Relay - Voltage Select
DISC Service Disconnect Non - Fused
DTD Discharge Temperature Dial
DTS Discharge Temperature Sensor
FOS Fan Operating Switch
     
FR Flame Rod
FSR Flame Safeguard Relay (HSI)
FU1 Fuse 24 Volt Control
FU2 Fuse 120 Volt Control
HL High Limit
IG Ignitor
L1 Light - Power
L2 Light - Air Flow
L3 Light - Burner
L4 Light - Alarm
LTC Low Temperature Cutout
M Motor - Blower
MV Modulating Valve
OT Operating Thermostat (optional)
RSS Remote Space Stat (optional)
SOV Shut-off Valve - Gas
SSV Safety shut-off Valve - Gas
SW1 Blower Service Switch
SW2 Switch - SOV Leak Test
SW3 Switch - Operating Mode Selector
SW4 Switch - Voltage Selector
T1 Dual Output Transformer
T2 Class 2 Transformer (24 Volt)
VFD Variable Frequency Drive

RxHeat, LLC 12 RX-Series Technical Manual





GAS


Minimum gas supply pressure
for maximum input adjustment
20" wc
(50 mbar)
5 PSI
(.35 bar)
Minimum gas supply pressure
to maintain ame signal
1.0" wc
(2.5 mbar)
1.0" wc
(2.5 mbar)
Maximum gas supply pressure 10 PSI
(.69 bar)
10 PSI
(.69 bar)
Valve
Supply
Valve
To Burner
Shut-off
4
1
223
76
Drip Leg
5
Shut-off Valve
Manual Burner
Leak Test
Tap for Valve
Valve
Shut-off
Supply
Gauge
Pressure
Inlet
Supply
Disconnect
Male Gas Quick
Regulator
Appliance
Valve
Shut-off
Manual
Safety
Modulating
Gas Train Components

RX-Series Technical Manual 13 RxHeat, LLC

Burner
Peephole
Cover
26
Low
Cutout
Temp
25
Operator Interface
(Cover panel removed)
15
17 16
12a
9a
8
14
9b
10
11
12b
13a
Air Volume Control
Burner On Light (Red)
LTC Reset Light (Amber)
RxSmart Selector Switch
Air Flow Light (Green)Discharge Temperature Selector Dial
Power On Light (Green)
Voltage Selector Switch
Disconnect Handle
OT Interface RSS Interface
Burner Operating Switch
Blower Operating Switch
TM
13b
Door Latch
VFD
Electrical Control Enclosure
20
21
23d 23a 23b
18
30
28 29
31 22
24
27
Disconnect
Switch
Service
Blower
Switch
Test
Leak
208/230
Voltage Select
Control Relay #4
Gas Valve On
Relay #2
Control
Gas Valve On
Relay #1
Control Call for Blower
Amplifier
Relay #3
Control
Relay
Safeguard
Switch
Airflow
Transformer
Class II
Transformer
Control
Fuse 1
Control
Fuse 2
Control
Flame
Limit
Temperature
High
Discharge
32
Sensor
Temperature
T1 Terminal
Block
23c
19
T2 Terminal
Block
07-21-09 1:45PM
Operator Interface Panel
(Cover panel removed)

RxHeat, LLC 14 RX-Series Technical Manual

Rx15 Component Parts List
Item Location (Manual Page) Description Part Number
1 Gas Train Valve - Gas Modulating M611 24-033
2 Gas Train Valve - Gas Shut Off 21-118
3 Gas Train Regulator - Appliance lbs. to inches 24-008
4 Gas Train Manual Burner Shut-off Valve 24-020
5 Gas Train Manual Supply Gas Shut-off Valve 24-115
6 Gas Train Gauge - Supply Pressure 23-633
7 Gas Train Supply Gas Quick Disconnect - 1” NPT 44-123
8 Operator Interface DFTD (Temperature Selection Dial) 23-218
9a Operator Interface Power On Light (Green) 22-601
9b Operator Interface Air Flow Light (Green) 22-601
10 Operator Interface Burner On Light (Red) 22-602
11 Operator Interface LTC Reset Light (Amber) 22-600
12a Operator Interface Voltage Select Switch 22-314
12b Operator Interface Blower Operating Switch 22-314
13a Operator Interface Burner Operating Switch 22-327
13b Operator Interface RxSmart™ Select Switch 22-327
14 Operator Interface Air Volume Controller 22-104
15 Operator Interface Disconnect Handle 22-276
16 Operator Interface Remote Space Sensor Female Connection 22-529
17 Operator Interface Thermostat Connection 22-526
18 Control Enclosure Disconnect 40A Non-Fused 22-269
19 Control Enclosure VFD 3HP 230v 1ph 23-903
20 Control Enclosure Blower Service Switch 22-040
21 Control Enclosure SOV Leak Test Switch 22-762
22 Control Enclosure Air Flow Switch (0.25” Setpoint) 21-124
23a Control Enclosure Control Relay - Gas Valve On 22-761
23b Control Enclosure Control Relay - Gas Valve On 22-761
23c Control Enclosure Control Relay - Call For Blower 22-761
23d Control Enclosure Control Relay - Voltage Select 208/230 22-761
24 Control Enclosure Flame Safeguard Relay 21-142
25 Control Enclosure Discharge Temperature Sensor 23-220
26 Control Enclosure Switch - High Temp Limit - 250°F 23-168
27 Control Enclosure Amplifier - Solid State (DFC -1) 23-217
28 Control Enclosure Control Fuse 6.25 amp 22-019
29 Control Enclosure Control Fuse 1.6 amp 22-078
30 Control Enclosure Transformer Dual Output - 350va 22-111
31 Control Enclosure Transformer Class 2 - 40va 22-693
32 Control Enclosure Low Temperature Cutoff 21-161
Not Shown Power Inlet, Twist Lock 22-141
Not Shown Remote Space Sensor Male Connection 22-528
Not Shown Room Space Sensor 23-221
Not Shown Battery for RSS 23-222
Not Shown 50ft. LP Supply Hose 1” NPT 44-124
Not Shown Gas Quick Disconnect - Female 1” NPT 44-125
Not Shown Flame Rod 21-062
Not Shown Igniter - 24v Hot Surface 21-097
Not Shown 12” Dia. Flexible Duct - Length 24ft. 44-126
Not Shown 4 ft. Power Cord 19-06936
Not Shown 75ft. Power Cord 19-06905

RX-Series Technical Manual 15 RxHeat, LLC

Contact the RxHeat Customer Service Group at 1-866-432-8297.

mWARNING:
The heater area must be kept clear and free from combustible
materials, gasoline, and other flammable vapors and liquids.
The flow of combustion and ventilation air must not be obstructed.
mWARNING:


has been shut down. Allow heater to cool before performing service, maintenance
or cleaning. Failure to follow this warning will result in burns causing injury.

The heater should be inspected before each use, and at least
annually by a qualified service technician.

Motors are pre-greased normally with Shell “Dolium R”. Equivalent greases which are compatible with the motor fur-
nished grease are Chevron “SRI No. 2”and Texaco “Premium RB”.

Using a Browning Belt Tension Checker and a straight edge, attain proper tension according to the following table:
Periodic belt adjustments may be required. Indications of loose belts include barking or squealing when the blower starts.
6 months
HOURS OF SERVICE PER YEAR
Motor Frame Size
5000 Hours
Continous Normal Application
Seasonal Service Motor Is Idle For
6 Months Or More
Continous High Ambients, Dirty Or Moist
Locations, Or High Vibration
SUGGESTED RELUBE INTERVAL
NEMA FRAME SIZE
42 to 215T
5 years
2 years
1 year (Beginning of
Season)
1 year
(Beginning of Season)
  
3 

RxHeat, LLC 16 RX-Series Technical Manual

mWARNING:
The heater shall be periodically evaluated, at least annually, for the seal tightness
of the electric shut-off valves.
The heater is equipped with a leak test facility to assist in checking these seals. A momentary switch and a gas port
for measuring pressure between valves are provided as the leak test hardware. The procedures for the electric shut-off
valve leak check are as follows.
A. Connect a 0 to 10 inches water column (" wc) manometer to the 1/8" NPT tapped fitting located just prior
to the burner. Verify the manometer is properly zeroed.
B. To check the tightness of second electric shut-off valve (SSV), close the manual burner shut-off valve,
hold the momentary leak test switch in the closed position and wait 30 seconds to read the manometer. If the
reading is greater than 0" wc, refer to the Maintenance Instruction Section for information on Gas Valve
Cleaning for the second electric shut-off valve (SSV) and retest. If reading is 0" wc, remove the manom-
eter, install the pipe plug and open the manual burner shut-off valve.
C. To check the gas tightness of the first electric shut-off valve (SOV) in the gas train, connect the manom-
eter to the leak test port between the valves and wait 30 seconds to read the manometer. If the reading is
greater than 0" wc, refer to the Maintenance Instruction Section for information on Gas Valve Cleaning for the
first electric shut-off valve and retest. If reading is 0" wc, remove the manometer and install the
pipe plug.
mWARNING:

or a dry cloth to clean the interior of the heater and its components.

The blower wheel should be examined for accumulation of dust on the blades. These surfaces must be kept clean.
Dirt accumulation will result in significant air flow reduction and/or possible imbalance of the blower wheel.



The RxHeat burner is typically self-cleaning. However, if the application is extremely dirty or subject to heavy insect
infestation, it may become necessary to periodically clean the burner. Remove and clean the burner in accordance
with the following recommended procedures:
A. Turn the heater disconnect switch to the “OFF” position. Close the manual burner shut-off valve.
B. Loosen the union in the gas train.

RX-Series Technical Manual 17 RxHeat, LLC

Igniter is made of silicon carbide material and should be handled with care to avoid breakage.
C. Disconnect the ignition cable from the burner and remove the flame rod.
D. Examine the flame rod ceramic for cracks and replace if necessary. Clean dirt/grime build-up from the
insulator.
E. Remove the fasteners that secure the burner to the housing. The burner will then be free to slide out.
m


F. Clean the burner by back-flushing using high pressure air (40-80 psi). Continue back-flushing until dust
and debris has been completely expelled from the burner. Wipe all burner surfaces with a cloth to remove
any foreign matter.
mWARNING:

compressed air may drastically affect heater performance.
G. Perform Discharge Air Temperature Sampling Tube (see below) cleaning at this time.
H. Reassemble the burner using the above steps in reverse order.

With the Burner out of the unit, clean the Discharge Air Temperature Sampling Tube located inside the unit. The
Sampling Tube is located inside the discharge duct beyond the stainless steel burner extension(s). Clean the Sampling
Tube using high pressure air (40-80 psi) until all debris is completely removed from the Tube.

All solenoid valves should be cleaned periodically. The time between cleanings will vary depending on the medium
and service conditions. In general, if the voltage to the coil is correct, sluggish valve operation, excessive noise, or
leakage will indicate that cleaning is required.
mWARNING:
In the extreme case, faulty valve operation will occur and the valve may fail to open or fully close.

It is not necessary to remove the valve from the gas train for cleaning.
mWARNING:
To prevent the possibility of severe personal injury or property damage, turn off electrical power, close
the upstream manual gas valve, depressurize valve, extinguish all open flames and avoid any type
of sparking or igni

RxHeat, LLC 18 RX-Series Technical Manual

Disassemble valve and clean all parts as follows:
: If parts are worn or damaged, install a complete ASCO Rebuild Kit.
A. Remove the solenoid enclosure.
B. Remove the bonnet screws, valve bonnet, bonnet gasket, core/diaphragm sub-assembly and body gasket.
C. All parts are now accessible to clean or replace.
D. Lubricate the bonnet gasket and body gasket with a light coat of DOW CORNING®200 Fluid lubricant or
an equivalent high-grade silicone fluid.
E. Apply a light coat of RemGrit TFL 50®Dry Lubricant to: Valve seat; Valve body surface where
the diaphragm assembly contacts the valve body and body gasket; and the internal surface of the valve
bonnet where the diaphragm assembly contacts the bonnet when the valve is in the energized (open posi-
tion).
:
If the valve has been disassembled for inspection and cleaning only and a Rebuild Kit is not being
®
•Diaphragm assembly on both sides
•Main disc at base of core/diaphragm sub-assembly.
•Pilot disc at base of core assembly.
m:

the diaphragm assembly when lubricating pilot disc.
F. Replace the body gasket and the core/diaphragm sub-assembly with the closing spring attached. Locate the
bleedhole in the core/diaphragm sub-assembly approximately 30˚ CCW from the valve inlet.
G. Replace the valve bonnet and bonnet screws (6). Torque the screws in a crisscross manner to 100 ± 10
inch lbs. Replace the solenoid and make the electrical hookup.
mWARNING:
To prevent the possibility of severe personal injury or property damage, check valve for proper
operation before returning to service. Also perform a gas valve leak check and gas train leak check.

Parts marked with an asterisk (*) in the exploded views are supplied in Rebuild Kits.
When ordering Rebuild Kits for ASCO valves, order the Rebuild Kit number stamped on the valve nameplate. If the
number of the kit is not visible, order by indicating the number of kits required, and the Catalog Number and Serial
Number of the valve(s) for which they are intended.