Clarke CONTRACTOR GRH30 Instruction Manual

OPERATION & MAINTENANCE
INSTRUCTIONS
ORIGINAL INSTRUCTIONS DL0223
TWIN HEAD GAS RADIANT HEATER
MODEL NO: GRH30
PART NO: 6920019

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INTRODUCTION
Thank you for purchasing this CLARKE heater.
This portable gas radiant heater is designed to give safe, efficient and reliable
operation and is for use with Propane Gas only. Propane gas bottles are
readily available from builders merchants or gas suppliers.
The heater is intended for drying and the warming of commercial/industrial
buildings where adequate ventilation is provided.
• It must always be operated as prescribed in this manual.
• It is not intended for domestic use or for the heating of habitable areas.
• It is not intended to be used to reach and maintain a certain level of
human thermal comfort within an enclosed space.
• It is not intended to be used in enclosed areas with restricted ventilation.
• It is not for use in areas with high levels of fluctuating drafts.
• It is not intended for warming animals or live stock.
• We recommend the use of a carbon monoxide detector.
As with any equipment, optimum performance will only be achieved if the
correct application and servicing procedures are followed.
Proper combustion depends upon correct air flow and the heater must not be
modified or operated with parts removed or missing. Likewise, safety systems
must not be circumvented or modified in order to operate the heater.
Before attempting to use this product, please read this manual thoroughly and
follow the instructions carefully. In doing so you will ensure the safety of yourself
and that of others around you and you can look forward to your purchase
giving you long and satisfactory service.
GUARANTEE
This product is guaranteed against faulty manufacture for a period of 12
months from the date of purchase. Please keep your receipt which will be
required as proof of purchase.
This guarantee is invalid if the product is found to have been abused or
tampered with in any way, or not used for the purpose for which it was
intended.
Faulty goods should be returned to their place of purchase, no product can
be returned to us without prior permission. This guarantee does not effect your
statutory rights.

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GENERAL SAFETY PRECAUTIONS
Read and ensure you fully
understand the following precautions
and the hazards associated with this
type of equipment.
1. Check the heater thoroughly for
damage. NEVER operate a
damaged heater.
2. DO NOT modify the heater or
operate a heater which has been
modified.
3. Use only propane gas (LPG).
4. Use only a VAPOUR WITHDRAWAL
propane supply. If there is any
question about vapour with-
drawal, ask your propane dealer.
5. Position the propane bottle
vertically (shut-off valve up).
Secure it from falling or being
knocked over and protect from
damage.
6. DO NOT direct the heater towards
the gas bottle.
7. IMPORTANT: Use only the hose
and regulator assembly provided
with the heater. Inspect the hose
assembly before each use of the
heater. If there is excessive
abrasion or wear, or hose is cut,
replace with the hose assembly
listed on the parts list (page 14)
before using the heater.
8. Position the heater such that it is
not directly exposed to water
spray, rain and/or dripping water
9. This heater is for indoor use only in
well ventilated areas.
10. If at any time, gas odour is
detected, IMMEDIATELY STOP
operation until the source of the
gas has been located & rectified
11. DO NOT use to heat or cook food.
12. DO NOT place the heater near
combustible materials such as
curtains, furniture etc. Allow at
least 1 metre clearance.
13. Due to the high surface
temperatures, users must observe
sufficient clearance to avoid
burns or clothing ignition.
14. Place the bottle on a firm, level
surface.
15. DO NOT use with ductwork. DO
NOT restrict air circulation.
16. DO NOT move, handle or clean
while hot or burning.
17. Use only in accordance with local
codes of practice.
18. DO NOT apply any torsional stress
to the hose.
19. DO NOT leave the heater
un-attended, for example, left on
at night.
20. The heater is designed to heat
enclosed areas such as
workshops. DO NOT use the
heater for any other function. It is
not suitable for drying clothes or
laundry.
21. Young children must be kept
away unless continuously
supervised.

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FRESH AIR REQUIREMENTS
•DO NOT use in unventilated areas.
• The flow of combustion and ventilation air must not be obstructed.
RISKS OF CARBON MONOXIDE POISONING
Even though this heater operates very close to 100 percent combustion
efficiency, it still produces small amounts of carbon monoxide.
• Carbon Monoxide (CO) is toxic.
• Pregnant women, persons with a heart or lung condition, anaemia
or under the influence of alcohol, or those at high altitude, are more
likely to be effected by Carbon Monoxide.
• CO can build up in a confined space and failure to provide
adequate ventilation can be fatal.
The early symptoms of carbon monoxide poisoning are:
•headaches
• dizziness
•nausea
• dry mouth or sore throat
•blurredvision
• shortness of breath
• confusion
• loss of consciousness
Should anyone show these symptoms they must GET FRESH AIR IMMEDIATELY.
Turn off the heater and have it serviced before using it again.
Be sure to follow all warnings in this manual.
WE RECOMMEND THE USE OF A CARBON MONOXIDE DETECTOR
WARNING: PROVIDE AT LEAST A 1M2OPENING OF FRESH, OUTSIDE AIR
WHILST USING THIS HEATER. IF FRESH OUTSIDE AIR VENTILATION IS NOT
PROVIDED, CARBON MONOXIDE POISONING CAN OCCUR.

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Parts & Service: 020 8988 7400 / E-mail: [e-mail] or [e-mail]
IF YOU SMELL GAS
Liquid Propane gas has a man-made
odourant added specifically for
detection of gas leaks.
If a leak occurs you should be able to
smell the gas. Since Propane (LP) is
heavier than air you should smell for
the gas odour near to the floor. ANY
GAS ODOUR requires immediate
attention.
1. DO NOTHING that could ignite the
gas. DO NOT operate any
electrical switches. DO NOT
unplug any power supply or
extension cables. DO NOT light
matches or cause any other
source of flame or spark. DO NOT
use your phone.
2. Get everyone out of the building
and away from the area
immediately.
3. Close all propane (LP) gas bottle
fuel supply valves.
4. Propane (LP) gas is heavier than
air and may settle in low areas.
When you have reason to suspect
a propane leak, keep out of all
low areas.
5. Call your fire department. DO NOT
re-enter the building or area.
6. Stay out of the building and away
from the area until declared safe
by the firefighters.
7. FINALLY. Let the firefighters check
for escaped gas. Have them
ventilate the building and area
before you return. Properly
trained service people must repair
any leaks, check for further
leakages and then re-light the
heater for you.
8. IF YOU SMELL EVEN A SMALL
AMOUNT OF GAS, CONTACT YOUR
FIRE DEPARTMENT. DO NOT WAIT!
NO ODOUR DETECTED
1. Some people cannot smell the
odour added to propane (LP).
You must determine if you can
smell the odourant in this fuel.
2. Learn to recognize the odour of
propane (LP) gas. Local propane
(LP) gas dealers may give you a
“scratch and sniff” pamphlet. Use
it to become familiar with the fuel
gas odour.
3. Smoking can decrease your
ability to smell. Being around an
odour for a period of time can
affect your sensitivity to that
particular odour. Odours present
in animal confinement buildings
can mask fuel gas odour.
ODOUR FADING
1. The odourant in propane (LP) gas
is colourless and the intensity of its
odour can fade under some
circumstances.
2. Propane (LP) gas odour may differ
in intensity at different levels.
Since Propane (LP) gas is heavier
than air, there may be more
odour at lower levels.
3. Always be sensitive to the slightest
gas odour. If you continue to
detect any gas odour, no matter
how small, treat it as a serious
leak.

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FEATURES OF THE GRH30
Understanding the basic operation of the heater will reinforce the need to
maintain it in top condition at all times whilst always observing the safety
precautions.
The heater comprises of three basic systems:
1. The gas system.
2. The ignition system.
3. The safety control system.
GAS SYSTEM
The gas supply to the heater is by means of a high pressure hose, connected
to a LPG bottle via a pressure regulator. When the gas shut off valve is
opened, gas will flow to the control valve and finally into the burner.
This heater is designed for use with PROPANE GAS ONLY. Gas bottles are readily
available from builders merchants or gas suppliers etc.
This heater is designed to operate with a minimum 20 pound (9 kg) propane
bottle. Note that less gas is vaporised at lower temperatures. Your local
propane gas dealer will help you select the proper gas supplies.
IGNITION SYSTEM
A Piezo-electric igniter is positioned at the burner head. When the igniter
button is depressed a high intensity spark is generated which ignites the gas.
Heat from the flame is sensed by a thermocouple connected to the control
valve. As the thermocouple heats up, the control valve opens so that after a
short period, the control valve button (see Operation page 10) may be
released and the gas flame is established.
SAFETY CONTROL SYSTEM
Should the flame extinguish for any reason the thermocouple will quickly cool,
causing the control valve to close, shutting off the gas supply.
Additionally, the heater is fitted with a ‘Tip Over Switch’ which operates should
the heater be tilted by more than 35-40 degrees, thereby shutting off the gas
supply.

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INSTALLATION
UNPACKING
Remove the heater from the carton and remove all protective material used
for shipment. Check the heater for possible shipping damage. Should any
damage be apparent, please notify your CLARKE dealer immediately.
ASSEMBLING THE SUPPORT STAND
1. Connect the tube base section to the
upper tube support section and secure
with the wing nut supplied.
2. Connect the support bracket to the
tube base section as shown and secure
with the wing nuts supplied.
LOCATING THE HEATER
Although a ‘tip-over’ switch is fitted, the heater and propane gas bottle must
both be located on a hard, level surface to minimize the risk of accidental
tipping. The propane gas bottle should be adequately restrained if needed.
Only operate this heater with the supply bottle in the upright position.
This heater must only be used in locations where the potential for damage to
the heater or personal injury (burns), is reduced to a minimum.
The heater must be located where it will not be exposed directly to rain and/or
dripping water.
Use of this heater in a drafty area reduces its efficiency. Wherever possible,
operate in a draft free area.
The heater must always be directed away from the propane gas bottle.
Position the heater at a safe distance of 1 metre from combustible materials.
The heater must not be used on floors covered in combustible materials.

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GAS CONNECTION
The hose for connecting the heater to the gas bottle is supplied loose and
must be fitted by the user.
Make the connection to the propane bottle in a well ventilated area using the
regulator and hose assembly supplied.
1. Attach the hose to the inlet
connection and tighten using a
9/16 spanner.
2. Remove the protective plug by
unscrewing clockwise.
3. Attach the regulator to the gas
bottle ensuring the bottle
connection is perfectly clean. Blow
out with compressed air if
necessary to blast away any dust or
dirt. (Use eye protection when
working with compressed air).
WARNING: PROPANE GAS BOTTLES MUST BE USED AND STORED IN
ACCORDANCE WITH THE ‘HIGHLY FLAMMABLE LIQUIDS AND LIQUEFIED
PETROLEUM GASES REGULATIONS 1972.
WARNING: IF YOU DO NOT FOLLOW THESE INSTRUCTIONS EXACTLY, A
FIRE OR EXPLOSION MAY RESULT CAUSING PROPERTY DAMAGE,
PERSONAL INJURY OR LOSS OF LIFE.

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Parts & Service: 020 8988 7400 / E-mail: [e-mail] or [e-mail]
4. Check the bullnose connection on
the regulator for any visible
damage before connecting to the
bottle.
5. Place the regulator on the bottle
connection and hand tighten by
turning anti-clockwise.
6. Tighten firmly using a gas spanner
(or an adjustable spanner),
continuing in an anti-clockwise
direction.
7. Simply turn the valve hand wheel anti-clockwise when you need to start
the flow of gas. Ensure that you turn the bottle off when not in use.
8. In order to reduce the risk of icing up when operating for long periods at
maximum capacity, you should use a larger capacity gas bottle.
9. Open the bottle gas valve and check all gas connections with a soap and
water solution ONLY. NEVER USE A FLAME.
10. Use a full bottle wherever possible with good air circulation and no frost on
the bottles.

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OPERATION
FIRST USE
Read these instructions carefully. DO NOT allow anyone who has not read the
instructions to light, adjust, or operate this heater.
DO NOT attempt to operate the heater with any fuel other than LPG (liquid
propane gas).
The heater reaches a very high temperature and during first use you may
notice an odour coming from the heater. This is quite normal and will disperse
quickly.
(It is recommended the heater is initially run outdoors on the first occasion to
enable the odour to clear).
Set the burner at the required angle to project the heat forward as shown.
WARNING: BEFORE STARTING THE HEATER YOU MUST ENSURE THAT THE
MINIMUM VENTILATION REQUIREMENTS ARE OBSERVED TO AVOID THE
RISK OF CARBON MONOXIDE POISONING.
WARNING: THIS HEATER WILL BE HOT DURING NORMAL OPERATION.
AVOID PHYSICAL CONTACT. DO NOT ALLOW CLOTHING OR OTHER
COMBUSTIBLE MATERIALS TO TOUCH THE HEATER.