background image

26

Heater Component Function

Air Proving Switch

Safety device used to insure that the proper air flow is being
achieved before the gas valve is opened.

Burner

Cast iron component used to channel gas and provide an
area at which the fuel may ignite.

Burner Orifice

Brass metering device used to feed gas to burner at a
specific rate.

Fan Housing

Chamber used for delivering air for efficient air movement.

Fan Wheel

Component used in conjunction with the motor and fan
housing to pull the hot air from heater and blow it into room
for heating (also known as a squirrel cage).

Gas Control Valve

A device which consists of a low pressure regulator and
electrical solenoids which are used for the control of gas
flow to the burner assembly.  A feature of the control is a
built in gas shut off which is used to isolate the heater from
its gas supply when servicing.

Gas Hose

Flexible connector used to convey gas from supply line in
building to heater.

Heat Chamber

Metal “fire box” within the appliance that provides an area
where burner flame mixes with combustion air, thereby
providing heat.

High Limit Switch

Safety device wired into the control system which is used to
break an electrical circuit to the gas control valve in event of
overheat situation.

Hot Surface Igniter

Ignition device used on automatic ignition control systems.
Ignites gas by surface temperature rather than spark or
flame.

Ignition Control Module

Electronic printed circuit board which sends and receives
voltages to various controls in an automatic ignition system.
An important safety feature of the control board is that it will
shut down the entire heater, thereby stopping the flow of
fuel gas if burner flame goes out.

Motor

Electric device used to force preheated air through the
heater and to circulate heat within a certain area.  Converts
electrical energy into mechanical energy.

Motor Relay

Electrical component wired between ignition control and
motor.  Used to feed voltage to motor upon receipt of voltage
from ignition control.

Regulator

Mechanical device used in L.P. and natural gas distribution
systems to reduce a higher inlet pressure to a preset lower
pressure.  The regulator is responsible to supply a steady
outlet pressure to the heater(s) despite changes in inlet
pressure, heater demand and weather conditions.

Thermostat 

(Accessory)

Electrical device used as an automatic “on/off” switch
which will respond to changes in temperature in a certain
area.  Can be wired so contacts in the thermostat open or
close on temperature increase or decrease.

Transformer

Electrical control used to accept line power supply primary
voltage and reduce it to lower secondary voltage to operate
certain control systems.

Summary of Contents for Therma Grow 120NG

Page 1: ...s Manual and Instructions Therma Grow Greenhouse Heaters View this manual online at www lbwhite com 150 27595 REV B ATTENTION ALL USERS This heater has been tested and evaluated by C S A Internationa...

Page 2: ......

Page 3: ...s heater can result in Death Serious bodily injury or burns Property damage or loss from fire or explosion Asphyxiation due to lack of adequate air supply or carbon monoxide poisoning Electrical shock...

Page 4: ...stributor dealer or the L B White Company Contact your local L B White distributor or the L B White Co Inc for assistance or if you have any questions about the use of the equipment or its application...

Page 5: ...d electrically interlocked with the heater to prevent heater operation if air inlet and exhaust outlet do not open when heating is required Model Indoor Mounting Air Exchange Requirements 1 Burner Man...

Page 6: ...lding and area before you return Properly trained service people must repair the leak check for further leakages and then relight the appliance for you WARNING n Do not use this heater for heating hum...

Page 7: ...ipped with a manual reset high limit switch and an air proving switch Never operate this heater with any safety device that has been bypassed Do not operate this heater unless all of these features ar...

Page 8: ...ground or to a height that would prevent snow blockage of heater s air inlet Refer to instructions provided in the optional L B White outdoor mounting and ducting kit part number 23579 4 The heater mu...

Page 9: ...appropriate alarms 16 Take time to understand how to operate and maintain the heater by using this Owner s Manual Make sure you know how to shut off the gas supply to the building and also to the indi...

Page 10: ...MI HD220 HD220 5B ENG BYNAME JIMI HD220 HD220 5B ENG BYNAME JIMI HD220 HD220 5B ENG BYNAME JIMI HD220 HD220 5B ENG BYNAME JIMI HD220 HD220 5B ENG BYNAME JIMI HD220 HD220 5B ENG BYNAME JIMI HD220 HD220...

Page 11: ...consideration must be given to making sure the heater is located away from the people entering or exiting the greenhouse so they cannot accidentally knock the heater or tamper with the heater and its...

Page 12: ...NTROL VALVE INLET REGULATORVENT GAS FLOW 1 Always use approved pipe thread compound suitable for use with L P gas or natural gas on the threaded connections 2 Assemble the components together accordin...

Page 13: ...roximately 17 seconds After igniter warm up time has been achieved the motor will start again and shortly thereafter ignition will occur NOTE It is normal for air to be trapped in the gas hose on new...

Page 14: ...Periodic cleaning and inspection as well as proper maintenance are essential to avoid serious injury or property damage 1 The area surrounding the heater shall be kept clear and free from combustible...

Page 15: ...ent jumpered Replace the part immediately An alternate method for checking the components is to perform a continuity check 5 Do not jumper the air proving switch If jumpered the ignition control will...

Page 16: ...m the switch which indicates the contacts of the switch have opened 4 Allow the switch cool down for about a minute before firmly pressing the red reset button on the switch 5 Check for electrical con...

Page 17: ...further checking or adjustment is required Proceed to section D 3 If the inlet pressures do not agree with that specified on the dataplate then the regulator controlling gas pressure to the heater req...

Page 18: ...ocated at the end of the igniter leads See Fig 16 2 Loosen the screw securing the igniter shield and the igniter to the mounting bracket Remove the igniter and shield 3 Ensure the igniter is located s...

Page 19: ...ition control Red light on ignition control is illuminated Ignition control sends flame sense current to flame sensor Ignition control module performs self safety check Internal components are tested...

Page 20: ...ace thermostat Is heater connected to power supply No No No Yes Ensure heater is connected to power supply Check breakers Is transformer receiving proper voltage Check wiring for continuity between tr...

Page 21: ...r proving switch been jumpered Yes No Remove jumper from switch Rapid Flash Reverse polarity Have electrician check neutral and hot wire connections that outlet heater is connected to Long Flash Two s...

Page 22: ...sary No Is fan wheel plugged with dirt Is there an obstruction in blower outlet preventing air proving switch closure No Are 115 volts sent from ignition control terminal IND to motor relay No If impr...

Page 23: ...e and component Repair or replace as necessary or replace ignition control Provide proper pressure to heater and check with a gauge Check for voltage to switch Check wiring and repair if defective If...

Page 24: ...l Flame sense is low and that flame failure or improper operation can occur at any time See flame sensor related problems in three time flash pattern Four Times If HSI board does not reset then replac...

Page 25: ...24 Electrical Connection and Ladder Diagram 115 Volt Supply 120 VOLT...

Page 26: ...25 230 Volt Supply 120 VOLT...

Page 27: ...ation Hot Surface Igniter Ignition device used on automatic ignition control systems Ignites gas by surface temperature rather than spark or flame Ignition Control Module Electronic printed circuit bo...

Page 28: ...27 28 30 37 38 39 21 20 19 16 17 6 5 7 8 9 10 11 12 4 3 2 1 14 31 32 33 34 35 26 27 29 36 22 25 13 18 15 24 23 Parts Identification PARTS SCHEMATIC...

Page 29: ...r Igniter Shield 572512 18 Bracket w Screws 570089 19 Flame Sensor 520139 20 High Limit Switch LP Gas 572501 Natural Gas 505566 21 Heat Chamber LP Gas 572499 Natural Gas 572500 22 Control Box w Cover...

Page 30: ...of the equipment and in any event L B White s liability in connection with the equipment including for claims based on negligence or strict liability is limited to the purchase price Some states do no...

Reviews: