Water Piping And Trim - Thermal Solutions APEX APX425C Installation, Operating And Service Instructions

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Water Piping and Trim

NOTICE: Failure to properly pipe boiler may result in improper operation and damage to boiler or structure.
Install boiler so that the gas ignition system components are protected from water (dripping, spraying, rain, etc.)
during appliance operation and service (circulator replacement, etc.).
Oxygen contamination of boiler water will cause corrosion of iron and steel boiler components, and can lead to
boiler failure. Thermal Solutions' Standard Warranty does not cover problems caused by oxygen contamination
of boiler water or scale (lime) build-up caused by frequent addition of water.
Do not fill boiler with softened water to prevent chloride contamination.
Installation is not complete unless a safety relief valve is installed into the tapping located on left side of
appliance or the supply piping.
A. Installation of Factory Supplied Piping
and Trim Components
1. Install provided components per Figure 6-1 for
APX425C or Figure 6-6 for APX525C through
APX825C. Rear tapping is return/inlet. Front
tapping (middle on APX425C) is supply/outlet.
Piping and trim components are located in
miscellaneous parts carton shipped with the
boiler.
a. Safety Relief Valve – Install on tee off 3/4
in. NPT tapping on APX425C or on tee
off supply tapping on APX525C through
APX825C. Use provided 10 in. long nipple
to locate valve above heat exchanger top.
Figure 6-1: Factory Supplied Piping and Trim Installation - APX425C
106308-05 - 3/23
APEX Installation, Operating, & Service Instructions
b. Drain Valve – Install on tee off 3/4 in. NPT
tapping on APX425C or on tee off supply
tapping on APX525C through APX825C.
c. Temperature and Pressure Gauge – Install
on supply piping.
d. Flow Switch – Install on supply piping.
Use provided tee with 1 in. NPT outlet.
Use correct paddle per Table 6-2. Refer to
Section 8 "Electrical" for flow switch wiring.
e. Install drain valve into tee bottom outlet.
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