Installing The System Piping; Installing A Space Heating System - Navien NCB-150E Installation & Operation Manual

3. Installing the System Piping

Prior to connecting plumbing to the boiler, flush the entire system
to ensure it is free of sediment, flux, solder, scale, debris or other
impurities that may be harmful to the system and boiler. During
the assembly of the heating system, it is important to keep the
inside of the piping free of any debris including construction and
copper dust, sand and dirt.
For retrofits, all system piping including radiators, must be cleaned
of all build-up including sludge and scale. All systems, old and new,
must be cleaned to remove flux, grease and carbon residue. Navien
recommends cleaning the boiler system with cleaning products
specially formulated for boiler systems. For retrofit applications
with heavy limescale and sludge deposits, a heavier duty cleaner
may be required. For information on performing the cleaning,
follow the instructions included with the boiler system cleaner
products.
WARNING
Failure to rid the heating system of the contaminants listed
above will void your warranty and may result in premature
heat exchanger failure and property damage.

3.1 Installing a Space Heating System

The primary and secondary heat exchangers of the Navien NCB-E
boiler are designed to attain the highest level of heat transfer in
a compact design. To accomplish this, the heating water flows
through a series of tubes (secondary heat exchanger) and finned
tubes (primary heat exchanger), designed to maximize the heat
transfer area. To maintain the efficient and reliable operation of the
heat exchangers, and to avoid heat exchanger failure, it is critical to
ensure the rules and guidelines in this section are followed.
CAUTION
Failure to follow the instructions provided in this section will
void the warranty and may result in property damage, fire,
serious injury or death.
3.1.1 Guidelines for a Space Heating Installation
Read and follow the guidelines listed below to ensure safe and
proper installation of a boiler heating system.
Freeze Protection for a Space Heating System
Freeze protection products may be used for the space heating
system. Freeze protection for new or existing systems requires
specially formulated glycol , which contains inhibitors to prevent
the glycol from attacking the metallic system components.
Before using freeze protection products, ensure that system
fluid contains proper glycol concentration and the inhibitor level
is appropriate. Navien recommends against exceeding a 35%
concentration of glycol.
When using the freeze protection products, the system must
be tested at least once a year, and as recommended by the
manufacturer of the glycol solution.
When using the freeze protection products, allowance should be
made for expansion of the glycol solution.
Freeze damage is not covered by the warranty.
WARNING
For systems requiring freeze protection, use only inhibited
propylene glycol, specially formulated for hydronic heating
systems; use of other types of antifreeze may be harmful to the
system and will void the warranty.
System Pressure
The Navien NCB-E boiler is intended solely for use in pressurized
closed loop heating systems operating with 12-30 psi water
pressure at the boiler outlet. To obtain the minimum system
design pressure, follow the piping diagrams illustrated in this
section.
The Navien NCB-E boiler's space heating system is not approved
for operation in an "open system", thus it cannot be used for
direct potable water heating or to process heating of any kind.
Installing the System Piping
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