Part number 550-143-010/1021
8
GV90+
series
2
gas-fired water boiler – boiler manual
Figure 5
Check for correct gas orifice plate
A
Remove jacket front
panel to access the bot-
tom side of the blower
housing.
B
Complete the propane
conversion label includ-
ed with the conversion
kit. Install label on jacket
left side, as shown.
Leave the boiler on its back,
on the skid as shown, until
you have checked the gas/air
orifice plate and replace it if
necessary.
Figure 6
Follow instructions to check or replace gas
orifice plate ("X" = boiler size)
1–4
Screws — follow instructions for loosening and tightening
5
Gas/air manifold
6
Front section, bottom view, component details omitted
7
Side shown must point toward air inlet hose — WARNING
label side for natural gas; WHITE side for propane gas
8
Propane orifice plate, RED one side and WHITE on the other
(red side must face the blower housing
9
Natural gas orifice plate, SILVER
10
Orifice plate after bending along score mark — label is visible
when installed
Check orifice plate — replace if
necessary
The
correct orifice plate
must be used. Failure to do
so will result in severe personal injury, death or sub-
stantial property damage.
The boiler is shipped with
a natural gas orifice plate. It MUST BE CONVERTED
to use propane.
Natural gas:
For natural gas installations,
inspect the silver gas/air orifice
plate marking
. It must be the same as the boiler size. If the orifice
plate is stamped with another size, obtain the correct plate from your
wholesaler. The boiler size is stamped where the “X” is shown in the
plate stamping, Figure 6.
Propane:
For propane installations,
replace the silver gas/air orifice plate
with the red/white plate
, per following instructions. Ensure the
red/white plate boiler size is correct for the GV90+ boiler being
installed. The boiler size is stamped where the “X” is shown in the
plate stamping, Figure 6.
Also fill out the propane label in the conversion kit and attach to
the left side of the jacket, above the gas inlet opening, as shown in
Figure 5.
Orifice plate installation, when required
Access the bottom of the blower housing as shown in Figure 5.
To inspect the plate only,
read the marking on the plate edge
. It
must read the same as the boiler size and fuel, as follows:
Boiler model
Natural gas marking
Propane marking
GV90+3
NG 3 SEC
LP 3 SEC
GV90+4
NG 4 SEC
LP 4 SEC
GV90+5
NG 5 SEC
LP 5 SEC
GV90+6
NG 6 SEC
LP 6 SEC
To replace the plate, using a
manual screwdriver or nut driver
,
see Figure 6:
1. Loosen screws
1
and
2
two full turns.
2. Remove screws
3
and
4
.
3. Pull the gas/air orifice plate forward to remove it.
4. Slide in the new plate as shown in Figure 6. The
red side of a
propane plate must go next to the blower housing
.
5. Replace screws
3
and
4
. Tighten all four screws securely and
uniformly.
DO NOT
overtighten.
DO NOT
exceed 40 inch-
pounds torque.
6. Bend down plate label tab at score mark as shown in lower right
corner of Figure 6, item 10.
DO NOT use electric or pneumatic screwdrivers to re-
move or tighten the gas/air boss screws. Hand-tighten
only, using manual screwdriver. Should the torque
exceed 40 inch-pounds, the threaded holes could strip
out, causing an inadequate seal of the orifice plate.
Failure to properly seal the plate to the housing could
result in a gas leak, causing severe personal injury,
death or substantial property damage.
Prepare the boiler
(continued)
