22
CAST IRON HEADERS
(ASME MODELS)
Heater must be located so that any water leaks will not
damage the structure of adjacent area. High tempera-
ture 2" plastic pipe (CPVC) may be threaded directly
into the header flanges. This is not the same as the
Schedule 80 PVC pipe which is also gray. PVC may be
used immediately after the supplied CPVC adapters.
DO NOT
use petroleum-based assembly fluids (such
as petroleum jelly or lubricating oil). If assembly lube is
WARNING:
NEVER install PVC directly into header
flanges. Use the 2" CPVC adapter supplied loose
with the heater.
INLET/OUTLET HEADER - ASME
Flange Gasket
Header Flange
UNITHERM GOVERNOR OPERATION
CAUTION:
The patented Unitherm Governor is a thermostatic
mixing valve specifically designed to maintain con-
stant heater internal temperature between 105° and
115°F despite continually changing flow rates from
the filter and changing pool temperatures. This nar-
row range is needed to prevent damaging condensa-
tion on the burners which will occur if the heater runs
for any length of time below 100°F. It is also needed
to inhibit scale formation in the tubes by maintaining
temperatures well below accelerated scaling temper-
atures.
U.G. Plug
(Polymer)
Unitherm
Governor
Gasket
POLYMER HEADERS
(STANDARD MODELS)
Before attaching the 2-inch unions to the inlet/outlet
header, make sure the O-rings are properly seated in
the grooves. Use AquaLube or equivalent non-petro-
leum-based lubricant on the O-ring.
Hand tighten the
unions.
Glue PVC piping directly to the unions.
INLET/OUTLET HEADER - POLYMER
High-temperature CPVC header flanges and header
flange nuts are provided. If there is any possibility of
back-siphoning when the pump stops, it is suggested
that a check valve (or valves) also be installed in the
system.
O-Ring
Header Flange
(CPVC)
Header Flange Nut
(CPVC)
GASKET DESIGN #1:
Accepts 1-1/2" copper tube or
1-1/4" galvanized pipe as a slip connection.
GASKET DESIGN #2:
Accepts 2" copper tube as a
slip connection. The flange is threaded for 2" screw in
pipe connections. Also used with the 2" CPVC
adapters.
#1
#2
Header
Header Flange
(Supplied)
CPVC Connector
(Supplied)
Plumbing
required, use a silicon base such as AquaLube etc.
There are two sets of flange gaskets supplied with
your heater. Use the appropriate gaskets for all your
heater connections. Discard unused set.
NOTE:
Some jurisdictions require the addition of a
flow switch and T&P gauge on ASME installations.
Kit # 013969 can be ordered that will allow a stan-
dard ASME unit to comply with the code require-
ments.
Summary of Contents for 336A
Page 28: ...28 WIRING DIAGRAM MILLIVOLT MECHANICAL THERMOSTAT...
Page 29: ...29 WIRING DIAGRAM ATMOSPHERIC...
Page 30: ...30 WIRING DIAGRAM LO NOx...
Page 48: ...48 19 M 20 M 22 M 24 M 23 M 21 M 22 M ATMOSPHERIC HEATERS...
Page 49: ...49 16 M 17 M 19 M 21 M 20 M 18 M 19 M LO NOx HEATERS...
Page 50: ...50...
Page 52: ...52 ATMOSPHERIC HEATERS...
Page 53: ...53 ATMOSPHERIC HEATERS...
Page 54: ...54 LO NOx HEATERS...
Page 55: ...55 LO NOx HEATERS...