18
MB Pool & spa heater
155 Model Only
Inlet/Outlet Header
DAN MAINES
Flange Gasket
Header Flange
S80
There are two sets of fl ange gaskets supplied with your
heater. Use the appropriate gaskets for all your heater
connections. Discard unused set.
DESIGN 1: Accepts 1½" copper tube or 1¼" galva-
nized pipe as a slip connection.
DESIGN 2: Accepts 2" copper tube as a slip connec-
tion. The fl ange is threaded for 2" screw in pipe con-
nections. Also used with the 2" CPVC adapters.
185, 265 & 405 Models Only
Ensure the O rings are properly seated before tight-
ening hand tight. They maybe lubricated with silicone
grease. Glue plastic pipe directly in to the unions.
UNITHERM GOVERNOR OPERATION
Does not apply to 105 Model
The patented Unitherm Governor is a thermostatic
mixing valve specifi cally designed to maintain con-
stant heater internal temperature between 40.6 to
46.1°C despite continually changing fl ow rates from
the fi lter and changing pool temperatures. This nar-
row range is needed to prevent damaging conden-
sation on the burners which will occur if the heater
runs for any length of time below 37.8°C. It is also
needed to inhibit scale formation in the tubes by
maintaining temperatures well below accelerated
scaling temperatures.
INTERNAL AUTOMATIC BY-PASS VALVE
Does not apply to 055 Model
In addition to the Unitherm Governor, a built-in
automatic by-pass valve is provided in the in/out
header. While the Unitherm Governor responds
to the changes in water temperature in the heater,
the internal by-pass valve automatically responds
to changes in water pressure in the piping system.
Proper amount of water fl ow is maintained through
the heater under varying pressures dictated by the
conditions of the pump and fi lter.
055 Models Only
055hdr.tif
IN
OUT
IN
OUT
105 Model Only
The 105 accepts direct connection to 1
½" plastic pipe
using the adapters provided.
Inlet/Outlet Header
1
½" NPT
Inlet/Outlet
Connections