UHA S
TANDARD
U
NIT
H
EATER
I
NSTALLATION
O
PERATION
AND
S
ERVICE
M
ANUAL
32 of 51
SECTION 13: SERVICING
13.1 Servicin
g
Instructions
After start-
u
p, the heater
w
ill req
u
ire maintenance to
be carried o
u
t, at a minim
u
m, ann
u
ally. If the heater
is
u
sed in a dirty or d
u
sty area, more freq
u
ent
maintenance may be req
u
ired.
IMPORTANT:
After any maintenance or repair
w
ork,
al
w
ays test fire the heater in accordance
w
ith the
start-
u
p instr
u
ctions
on Page 27, Section 11
through
Page 30, Section 11.3.1
to ens
u
re all safety systems
are in
w
orking order before leaving the heater to
operate. Minor fa
u
lts may be traced by
u
sing the
tro
u
bleshooting charts
on Page 35, Section 14
through Page 39, Section 14.5
.
IMPORTANT:
Check all gas pipes and pipe joints to
ens
u
re there are no cracks or gas leaks. Any cracks
in the pipes or pipe joints m
u
st be repaired.
IMPORTANT:
Inspect all s
u
spended components
and hard
w
are. Ens
u
re that they are in good
condition, properly tightened, and corrosion free.
13.2 Burner Maintenance
1. Open the door and remove the b
u
rner compart-
ment cover.
See Page 41, Section 15.2
.
2. Clean any deposits from the main b
u
rner
w
hich
may have formed in the injectors or vent
u
ri of
the b
u
rner.
See Page 41, Section 15.2
.
3. Remove the ignition electrode and flame probe.
Check condition of ignition electrode and flame
probe. Clean off any deposits
w
hich may have
been formed, check condition of ceramic
ins
u
lators. Replace as necessary.
See Page
42, Section 15.3
.
13.3 Fan/Motor Assembly Maintenance
The main fan bearings are permanently sealed and
do not need l
u
brication. Before cleaning, t
u
rn off gas
and electrical s
u
pply. Remove the fan and
u
se a
small br
u
sh or d
u
ster to clean the fan blades from
each side. Replace fan
w
hen done.
13.4 Heat Exchan
g
er Maintenance
The heat exchanger
w
ill remain clean
u
nless a
problem has developed
w
ith comb
u
stion. Inspect the
heat exchanger. Look for signs of overheating at the
front t
u
bes
w
hich may indicate b
u
rner over firing or
persistently lo
w
air flo
w
s.
13.5 Gas Valve Maintenance
No reg
u
lar maintenance is req
u
ired on this device.
To change gas control valves,
See Page 40, Section
15.1
.
Do not repair or disassemble
g
as valve.
Replace fa
u
lty gas valves
w
ith gen
u
ine replacement
parts sold and s
u
pplied by Roberts-Gordon LLC.
13.6 Flue Blower
The fl
u
e blo
w
er sho
u
ld not req
u
ire maintenance.
Ho
w
ever, if the air press
u
re s
w
itch is ca
u
sing b
u
rner
locko
u
t, then remove the fl
u
e blo
w
er from the vent
box by
u
nscre
w
ing the three scre
w
s at the mo
u
nting
plate. Remove the fo
u
r scre
w
s attaching the
mo
u
nting plate to the fan inlet (
See Page 44,
Section 15.6
). Ens
u
re that the fan is free to r
u
n and
that the fan
w
heel is clean.
Cut/Pinch Hazard
Wear protective gear
during installation,
operation and service.
Edges are sharp.
WARNING
Failure to follow these instructions can result in death, electric shock, injury or property damage.
Burn Hazard
Allow heater to cool
before service.
Tubing may still be hot
after operation.
Explosion Hazard
Turn off gas supply to
heater before service.
DANGER
Electrical Shock Hazard
Disconnect electric
before service.
Heater must be
connected to a properly
grounded electrical
source.