Parmet GP-300 Manual

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INSTALLATION AND SERVICE MANUAL
PARMET GP300/500/900
Contents
Section Title Page
1 Introduction 2
2 Location 2
3 Positioning the Unit 2
4 Combustion and Ventilation Requirements ...2
5 Flues ...3
6 Gas Pipe Connection 4
7 Electrical Connections 4
8 Commissioning Instructions 5
9 Maintenance Instructions 5
10 Users Instructions 6
Appendix A-Wiring Diagrams
Appendix B Burner Data
THIS APPLIANCE MUST BE INSTALLED IN ACCORDANCE WITH THE
MANUFACTURERS INSTRUCTIONS AND THE REGULATIONS IN FORCE AND
ONLY USED IN A SUITABLY VENTILATED LOCATION. READ THE INSTRUCTIONS
FULLY BEFORE INSTALLING OR USING THIS APPLIANCE WHICH MUST BE
INSTALLED BY A CORGI APPROVED ENGINEER

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1. Introduction
The Parmet Range of Gas Fired Warm Air
Heaters covers applications with outputs
from 300,000 to 800,000 Btu/h.
The standard unit is the free-standing unit
incorporating swivel type distribution heads.
These units are available with inlet and
outlets spigots suitable for connection to
ductwork.
2.Location
The installation of a warm air heating system
must conform with any fire regulations or
insurance requirements especially where
special risks are involved i.e. where there is
paint spraying, etc. Attention must be paid
where polyurethane based products are
used in the premises as these can cause
corrosion to the heat exchanger.
Installation of free blowing
PARMET air heaters:-
Position the air heater taking into regard the
position of the exhaust flue and avoid the
heater being obstructed by pillars or
shelving which could prevent the warm air
from circulating.
When more than one air heater is installed
in the same room it is good practice to
distribute the air in opposing directions.
If air is to be ducted from the appliance all
ducting should be made from non-
combustible material.
Where interjoist spaces are used as duct
routes they should be suitably insulated to
prevent excessive heat transfering to the
woodwork. A full unobstructed return air
path should be provided to enable the air to
return to the heater.
3. Positioning the Unit.
Free standing air heaters must be positioned
on a level base that is capable of supporting
the full weight of the unit.
Ensure that sufficient clearance is allowed
for, and maintained, around the heater to
facilitate easy access to the burner, main fan
assembly and heat exchanger for servicing
purposes and to allow unrestricted passage
of the return air unless the system is ducted.
WARNING:-
Clearance should be allowed for the
pressure relief to operate.
4. Combustion and
Ventilation Requirements.
Combustion Air
It is important to ensure that there is
sufficient air for combustion, especially
when a heater is positioned in an enclosed
area i.e.plant room.
The air supply requirements shown relate to
the total rated input of the heater(s). Size of
air vent given is for air direct from outside
and relates to the free area of the grill.

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(a) Heaters installed in the space being heated.
Up to 60 Kw 810cm2GP 300 410CM2
(Up to 204, 720Btu/h (1262)
Above 60 Kw 810cm2 + 6.45cm2/kW GP 400 550 CM2
in excess of 60 Kw.
(Above 294, 720 Btu/h) (126in2 + 1in2/Kw GP 500 720 CM2
in excess of 60 Kw)
GP800 1100CM2
(b) Heaters installed in a plant room.
Position of Air Vent
HIGH LOW
Low level 540cm2 +4.5cm2/kW GP300 820CM2 1640CM2
in excess of 60 kW
(83.7in2 + 0.7in2/kW in excess of 60 kW) GP400 1100CM2 2200CM2
High Level 270cm2 + 2.25cm2/kW GP500 1500CM2 3000CM2
in excess of 60 kW
(41.85in2 + 0.35in2/kW in excess of 60kW) GP800 2200CM2 4400CM2
Also the louvres to the fan compartment
must not be restricted in any way. If the unit
is fitted in an area of very high extract rate it
is necessary to duct the combustion air to the
burner via an air intake spigot fitted to the
burner.
The discharge heads can be turned to
change direction to the warm air stream.
Also the angle of the louvre on the heads
can be adjusted.
5. Flues
Flues:Should be installed in accordance with
BS5440:Part 1 or BS 5854 as applicable.
Stainless steel flue pipe is recommended.
The size for each heater is given in the table
below. The flue should preferably be fitted
with a condensate tee. Right angle bends
should be avoided where possible. The joints
should be sealed to prevent rain and moisture
from entering the systems. A recommended
flue installation is shown in Figure 1 below
Figure 1

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Model Flue
Size (Nominal Bore)
GP-300 230mm(9 in)
GP-400 230mm(9 in)
GP-500 230mm(9 in)
GP-750 255mm(10 in)
GP-900 255mm(10 in)
Wherever possible horizontal runs should
be avoided, but where this is unavoidable
everyone foot of horizontal flue must be
followed by three feet of vertical. If the total
flue height exceeds 8 metres please contact
our PARFLUE systems dept TEL 0161
330 3838.
The draft should not exceed
4mmWG (Positive)
Before the unit is operated a check must be
made to ensure that the flue has no
obstruction and terminates in such a
position that down draught is avoided. An
8mm(5/16in) diameter hole should be made
in the flue pipe approximately 1m (3 feet)
from the unit to see that the flue is pulling
and to make a check on combustion. This
check should be made after the unit has
been running for approximately 15 minutes.
6 Gas Pipe
The nominal inlet pressure for natural gas
should be 20mb(8in. w.g.)
. The pipe to the heater should be
adequately supported along its length, and
also contain as near to the heater as
practical a gas cock to enable the burner to
be removed for servicing. The units are
fitted with a main gas governor. This is
adjusted at the works to give the correct
rate for the appliance.
7. Electrical
The electrical supply position is located on
the front of the heater.
A CONTINUOUS ELECTRICAL
SUPPLY TO THE UNIT IS
REQUIRED
The GP 300 model requires an operating
voltage of 220/240v single phase. The rest
of the range 400 to 800 require 380/440v
three phase and neutral ,the burner utilising
one phase and neutral. Circuit diagrams are
attached to the inside of the lower front
panel.
On three phase units check the direction of
rotation of the main fan is correct. A
Honeywell CM51 controller time clock
room thermostat and frost thermostat is
supplied with each unit.
Positioning of the Controller is important
and care must be taken to avoid cold and
draughty areas and sites likely to be

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subjected to local heat gain e.g.in front of
windows allowing the sun to act directly on
the thermostat.
Note: The main electric supply should be
protected by a fused isolating switch rated
at:-
GP-300 13 Amps
GP-400 10 Amps 3 Ph.
GP-500 10 Amps.3 Ph
GP-750 20 Amps 3 Ph
GP900 20 Amps 3 Ph
The wiring to the appliance should be to
I.E.E. Regulations. An earth wire is
connected to the main terminal block in the
heater, as indicated in the wiring diagrams.
8. Commissioning
Instructions
Ensure that the gas and electricity supplies
to the appliance are turned off. Set the
thermostat to a minimum position.
Switch on the main electrical supply. Select
the ‘manual’ setting on the fan/limit stat,
which will then start the fan. Now switch to
automatic. If the fan should fail to start, try
to establish the cause (e.g. the blowing of a
fuse or a fault in the wiring). Disconnect the
main electrical supply.
Refer to the Burner Supplement supplied
with the heater and complete gas
soundness test on the burner controls
assembly.
Complete the specified tests in the
Commissioning and Testing section of the
Burner Supplement. The following is a
description of the sequence of events that
will occur each time the external control
circuit is completed.
With all the controls on and the thermostat
calling for heat, the burner starts up going
through a pre-purge period before ignition
takes place. Start gas is released and
ignited. The flame is sensed by an ionisation
probe which allows the control box to open
the main gas valve thus establishing main
flame.
On loss of flame or breakdown of the
rectification systems the control box will go
to lockout, and the rest button located on
the control box will light up. Press the
lockout button in order to rest the control
box.
The burner motor drives a fan which
provides air for combustion. The air
pressure that this fan produces is sensed
and used to operate a pressure switch. This
in turn signals the control box that air
circulation is proved. Any loss in air
pressure will automatically result in the
burner going to lockout.
Fitted to the burner is the main gas
electrically operated valves.
9. Maintenance
Instructions
A maintenance check should be carried out
annually. The check should be for safe and
reliable operation of the burner and flue
system, and any wear likely to take place
on switches or moving components.

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Before commencing maintenance, isolate
the unit from electricity supply.
Check and clean the main fan and vent and
housing. Check there is no impingement of
the housing.
Examine main fan bearing for wear..
Examine electrical connections for tightness,
any sign of cracked or weak insulation, and
all contacts for oxidisation.
Remove any dust or fluff from the heat
exchanger and air outlet heads. Remove the
access panel on the front of the heat
exchanger and remove baffel plates and
clear the flue way and flue systems. Replace
the fibreglass tape on location studs, and
ensure a good joint.
10. Users Instructions.
START UP AND OPERATING
SEQUENCE
1. Turn room thermostat to minimum, time
clock to OFF if fitted.
2. Check both gas and electricity supply is
live.
3. Turn room thermostat to required
position.
4. Switch clock to manual and the
sequential control fitted to the burner should
operate.
5. The sequence of events is:-
(1) Burner fans start.
(2) Air pressure switch made.
(3) Ignition on with start gas.
(4) Flame established and sensed,
ignition off.
(5) Main flame established.
6. If burner goes to lockout, press reset
button on control box.
7. If burner repeatedly goes to lockout call
service engineer.
FOR SPARES CONTACT:-
WILLIAM MAY (ASHTON) LIMITED
CAVENDISH STREET
ASHTON-U-LYNE
LANCS OL6 7QW
Tel: [phone]