Clarke GRH125 Operating & Maintenance Instructions

GAS HEATER

OPERATING & MAINTENANCE

INSTRUCTIONS

Model No: GRH125

GAS HEATER

0806

For Spare Parts and Service, please contact your nearest dealer,

or CLARKE International, on one of the following numbers.

PARTS & SERVICE TEL: [phone]

PARTS & SERVICE FAX: [phone]

or e-mail as follows:

PARTS: [e-mail]

SERVICE: [e-mail]

PARTS & SERVICE CONTACTS

SPECIFICATIONS

Rating BTU Output ................................ 125,000 Btu/hr

Gas Consumption - per hour .................. 2.6kg

Gas Hose Length .................................... 3610mm

Regulator Type ....................................... 37mbar

Dimensions ............................................ 475x400x1090mm

Weight unpacked ................................ 18.19kg

Part No. .................................................. 6920017

2

Thank you for purchasing this CLARKE Gas Heater, designed for commercial use
only, i.e. NOT for domestic use.

This portable gas heater is designed to BS 4096 for industrial applications, to give
safe, efficient and reliable operation, and is for use with Propane Gas only.
Propane gas bottles are not supplied with the unit, but are readily available from
Builders Merchants or gas suppliers.

As with all mechanical equipments, optimum performance will only be achieved
if the correct application and servicing procedures are followed.

Please read this leaflet thoroughly and follow the instructions carefully before
attempting to use the heater. In doing so you will ensure the safety of yourself
and that of others around you, and you can look forward to it giving you long
and reliable service. Keep this booklet safe for future reference, as any person
who has not read this booklet should not be allowed to operate the heater.

CONTENTS PAGE

Safety Precautions ........................................................................... 3

Electrical Connections..................................................................... 4

Wiring Diagrams ................................................................................ 5 - 6

Gas Connection ............................................................................... 7

Operation .......................................................................................... 7

Starting Procedure ........................................................................... 8

Stopping Procedure ......................................................................... 10

Maintenance .................................................................................... 10

Trouble Shooting ............................................................................... 11

Specifications .......................................................................................... 12

GUARANTEE

This CLARKE product is guaranteed against faulty manufacture for a period
of 12 months from the date of purchase. Please keep your receipt 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.

3

SAFETY PRECAUTIONS

WARN IN G!

Lack of ventilation can cause Carbon Monoxide poisoning.

Carbon Monoxide poisoning can kill.

Signs of Carbon Monoxide poisoning are, headaches, dizziness and/or nausea.
Should anyone show these signs, they must GET FRESH AIR IMMEDIATELY. Turn off
the heater and have it serviced before using again.

Pregnant women, persons with a heart or lung condition, anaemia or under the
influence of alcohol, or those at high altitudes, are more likely to be effected by
Carbon Monoxide than others.

Read, and make sure you fully understand the following precautions and the
hazards associated with this type of equipment.

• This heater is not designed for use on finished floors.

• NEVER move the heater when it is lit.

• Use ONLY Propane gas

• Ensure the Propane gas bottle, gas hose and electric cable, are positioned
well away from the heat... minimum distance of 6 feet (2M)

• Ensure all gas hose and regulator connections are GAS TIGHT, and the hose
is not kinked.

• NEVER use the heater where Gasoline, Paint thinner or other highly flammable
vapour or high dust content is present.

• Use ONLY in well ventilated areas. Provide a ventilation opening of at least
10 square feet to fresh, outside air.

• The minimum clearance from any combustible materials is 8 feet (205cm)
from the front and 4 feet (100cm) from the top and sides.

• ALWAYS locate the heater on a stable, firm level surface

• Keep children and animals well away from heater at all times.

• Use heater in accordance with all fire regulations.

• NEVER use heater in living or sleeping areas.

• NEVER leave a heater, when lit, unsupervised - an individual should always
be made responsible for monitoring it.

• NEVER move, handle, replenish gas supply or service the heater when it is
hot, or operating.

• Use ONLY the regulator supplied with the heater.

• If the heater works for long periods, be aware that it is possible for ice to form
on the cylinder, due to excessive evaporation. NEVER direct hot air towards
the cylinder in order to de-ice. The cylinder temperature should NEVER
exceed 100

O

F (38OC)

• ALWAYS store gas cylinders according to ‘Highly Flammable Liquids and

Liquefied Petroleum Gases Regulations 1972’

4

UNPACKING

On unpacking, check the heater for possible shipping damage. Should any
damage be apparent, please notify your Clarke dealer immediately.

Your heater is fully assembled, It is only necessary to connect the gas supply.

FEATURES

Understanding the basic operation of the heater, will reinforce the need to maintain the
unit in top condition at all times, whilst always observing the safety precautions.

The heater comprises three basic systems:

1. The gas system. 2. The ignition system. 3. The safety control system.

1. Gas System

The gas supply to the machine is by means of a high pressure hose, connected
to a LPG cylinder, via a pressure regulator.

When the gas valve is opened, gas will flow to the Control Valve and finally the burner.

This heaters is designed for use with PROPANE gas ONLY. Gas bottles are not
supplied, but are readily available from builders merchants or gas suppliers etc.

This heater is designed to operate with a minimum 20 pound (9 kg) propane
tank. You may need two or more tanks or one larger tank in colder weather. Use
a 100 pound (45 kg) tank for longer operation or in very cold weather. Less gas is
vaporized at lower temperatures. Your local propane gas dealer will help you
select the proper supply system. The minimum surrounding air temperature rating
for each heater is -20o F (-29oC).

2. Ignition System

A Piezoelectric Igniter is positioned at the Pilot Light. When the Igniter button is
depressed (C, Fig.2), a high intensity spark is generated, which ignites the gas.
Heat from the flame is sensed by a Thermocouple, which is connected to the
Flame Failure Valve. As the Thermocouple heats up, a low voltage is fed to the
Safety Cut-Off Valve, causing the valve to open, so that after a short period, the
Control Valve (see ‘Lighting the Heater on p8) may be released, and the pilot
flame is established.

3. The Safety Control System.

Should the flame extinguish for any reason, the Thermocouple will quickly cool,
causing the Flame Failure Valve to close, shutting off the gas supply.

5

6

VENTILATION

WARNING:

Provide at least a 10ft2 opening of fresh, outside air whilst running this
heater. If proper fresh, outside air ventilation is not provided, carbon

monoxide poisoning can occur.

INSTALLATION

Read these instructions carefully. Do not allow anyone who has not read these
instructions to light, adjust or operate this heater.

Do not attempt to operate the heater with any gas other than propane

This heater, including hose and regulator assembly, must be inspected before
each use and at least annually by a qualified service person. If the hose shows
evidence of excessive abrasion or wear or if the hose is cut, it must be replaced
prior to the heater being put into operation. The replacement hose assembly
shall be that specified by Clarke International.

Positioning the Heater

The heater and propane gas cylinder must be located on a hard, flat, level
surface to minimize the risk of accidental tipping. The propane gas cylinder should
be adequately restrained to prevent accidental tipping. DO NOT operate this

heater with the supply cylinder in any other than the upright position.

This appliance must be located only in places where the potential for physical
damage to the appliance, or to individuals (burns), is reduced to a minimum.

This appliance produces radiant heat. Therefore, it must be located at least 6
feet away from any propane gas cylinder and must not be directed toward any
gas container within 20 feet.

The heater must be located such that it will not be exposed directly to water
spray, rain and/or dripping water.

Use of this heater in a draft/windy area decreases its efficiency. If possible, operate
the unit in a draft free area.

7

OPERATING INSTRUCTIONS

WARNING:

If you do not follow these instructions exactly, a fire or explosion may

result causing property damage, personal injury or loss of life.

The heater must be positioned at least 6 feet away from the propane cylinder. If
more than one heater is used, they and the supply cylinders must be separated by
at least 20 feet.

CAUTION:

This appliance is hot during normal operation, avoid physical contact.

Do not place clothing or other combustible materials on this appliance.

DO NOT operate this heater if any part has been under water. Call a qualified
service technician to Inspect the appliance and to replace any part of the control
system or gas control valve which has been under water.

Gas Connection

The connection to a propane cylinder must be made in a well ventilated area
using the regulator and hose assembly supplied with the appliance. DO NOT
attempt to adjust this regulator. It has been preset at the factory to provide safe
and proper operation of the appliance.

Attach the regulator to the gas cylinder ensuring the cylinder orifice is perfectly
clean - blow out with compressed air if necessary, or open the gas valve quickly
and briefly to blast away any dust or dirt, Turn the nut in an anticlockwise direction

- i.e. LEFT HAND THREAD, until tight. DO NOT use a thread compound on threads.

To check for leaks, use soapy water, or liquid soap ONLY.

IMPORTANT: The gas hose and cylinder must ALWAYS be positionedat a distance
of at least 6 feet (2M) from the heater.

In order to reduce the risk of icing up when
operating at long periods at maximum
capacity, you should use a larger capacity
gas bottle, or two/three bottles in parallel, as
shown in Fig. 1.

The Tee piece and ‘pigtails’ are readily
available from Builders Merchants or gas
suppliers.

Fig.1

WARNING

Propane Gas cylinders must be used and stored in accordance with the

‘Highly Flammable Liquids and Liquefied Petroleum Gases Regulations 1972’

Lighting the Heater

WARNING!

Before starting the heater, you MUST ensure that the minimum ventilation

requirements are observed to avoid the risk of carbon monoxide poisoning.

1. Ensuring there is sufficient gas, and that it is correctly connected and
leak free - turn the Control Knob (Fig. 3) fully clockwise so that OFF is
uppermost. To do this you must first push the knob IN .

2. Turn on the gas supply and check
all fittings and connections for gas
leaks, by smell, and if necessary,
using a mild soap and water
solution. NEVER use a match to
check for gas leaks.

3. When satisfied, turn the Control
Knob anticlockwise to the ‘Pilot’
position.

4. Press and hold the Control Valve
IN, whilst repeatedly pressing the
Piezo Electric starter (C, Fig.2) until
the pilot light ignites. (The pilot light
may be viewed through the
window shown at ‘A’ Fig.2.

8

NOTE: If a new gas cylinder has been
connected, it may take some time for the gas
line to be purged of air. Press the Piezo electric
button every 10-15 seconds until the pilot
ignites.

Continue to hold IN the control knob for
approx. 1 minute, or until the pilot
light remains lit when it is released.

5. With the pilot light lit, turn the control
valve anticlockwise so that ON is
uppermost. The burner will now ignite.

NOTE: a. The heater, has a fixed, regulated gas flow

b. In cases where long runs of gas supply lines have been installed

ahead of the appliance, it may be necessary to bleed trapped air
out of supply lines before lighting pilot. New installations generally
require bleed of supply lines. It could take several minutes before
the pilot can be lit, depending upon the length of the supply line.

Fig.3

Fig.2

Shutting OFF the Heater

A. For Short Periods.

Simply turn the control knob clockwise to the ‘Pilot’ position.

B. For Prolonged periods.

1. Turn the Control Knob clockwise to the Pilot position, then push the knob IN
and turn a further quarter turn to the OFF position.

2. Close propane gas supply cylinder valve

9

CLEANING AND MAINTENANCE

WARNING: Never attempt to service heater while it is

(a) connected to propane supply,
(b) operating
(c) hot. (Severe burns can occur.)

1. Turn heater off and let cool at least 20 minute, before cleaning.

2. Keep heater clean. Clean it annually or as needed to remove dust and
debris. If heater is dirty or dusty, clean itwith a damp cloth. Use household
cleaners on difficult spots.

3. Inspect heater before each use. Check connections for leaks. Apply mixture
of liquid soap and water to connections. Bubbles forming show a leak. Correct
all leaks at once.

4. Clean inside heater using compressed air where possible. Blow air back
and forth along the entire burner face until all dust has been dislodged from
surface of the screen. Blow air through venturi from the control end (orifice)
of heater.

5. Inspect hose/regulator assembly before each use. If hose is badly worn or
cut, have it replaced.

6. Have heater inspected yearly by a qualified service agency.

Adjusting the Pilot Light

Pull off the control knob, then unscrew the Hex Head
screw immediately beneath the control block, to
reveal the adjuster screw, arrowed in Fig.4.

Adjust the pilot light so that it burns steadily with a blue
flame. It should not be yellow. Replace the Hex head
screw

Fig.4

TROUBLE SHOOTING

FAULT CAUSE REMEDY

10

Burner fails to light 1. Gas supply valve closed 1. Open gas supply valve slowly

2. Excess-flow check valve 2. Close propane supply valve on
closed propane tank and
reopen slowly

3. Blockage in burner orifice 3. Replace burner orifice

4. Piezo ignition not sparking 4. Assure igniter electrode gap is

5.0

mm

(0.195

in). Check wire
lead for damage Replace piezo
igniter and/or igniter electrode
as necessary. Do not bend
electrode, this may cause
breakage

No gas flow to the
burner

1. Cylinder gas tap closed.

2. Cylinder is empty.

3. The orifice is obstructed.

4. Gas leaks from the
supply hose or from
the tap.

5 Low gas pressure 5. Check for proper gas supply
6 Thermocouple loose or 6. Tighten connection or

needs to be replaced replace thermocouple

7. Automatic control valve 7 Replace automatic control
needs to be replaced valve

8. Loose wires on tip over 8. Tighten wires on tip over
switch switch

9. Loose or broken wire 9. Tighten or repair wire

10. Loose or dislocated 10. Tighten thermocouple. Make

sure thermocouple is located
correctly between
reverberator and grid
thermocouple wire

11. Defective thermocouple 11. Replace thermocouple

12. Defective control 12. Replace control

1. Open the gas tap.

2. Replace cylinder.

3. Remove the orifice and
clean it.

4. Use soapy water to find the
leak, and repair.

The Heater stops
during operation.

1. Excessive gas supply.

2. Insufficient gas supply
due to ice formation
on the cylinder.

3. The tip-over switch
has tripped.

1. Check the pressure regulator,
and replace if necessary.

2. Check, and use a larger
cylinder, or two or more in
parallel.

3. Investigate cause. If heater has
fallen over, right it and
investigate cause. Take steps to
prevent recurrence

11

PARTS LIST AND DIAGRAM

1 Manual Control Valve GRH12500332

2 Filter/ Diffuser GRH12504466

3 Pilot Orifice GRH12505363

4 Thermocouple GRH12509352

5 Pilot Burner GRH12511357

6 Regulator GRH12511663

9 Ignitor GRH125CR805

10 Piezo Starter GRH125CR835

11 Axle GRH125CR820

12 Axle Brackets GRH125CR815

13 Handle GRH125CR725

14 Wheel GRH125CR810

15 Valve Supply Tube GRH125M9005

16 Clamp GRH125M9010

17 Burner Manifold GRH125M9015

18 Burner GRH125M902 0

No. Description Part No No. Description Part No.

Use ONLY replacement parts supplied by CLARKE International.

The use of other parts, unless specified, could lead to fatal consequences and invalidate

your warranty.