16
A. GENERAL
1. Size water supply and return piping in accordance with
system requirements rather than the boiler connections.
2. If the Series PFC
TM
boiler is used to replace an existing
boiler, make sure the system piping is thoroughly
cleaned and free from debris before installing this
boiler. Sentinel Performance Solutions (http://www.
sentinel-solutions.net/us/) offers a full line of cleaners
(X300), sludge remover (X400), antifreeze (X500)
and corrosion inhibitors (X100/X500) for hydronic
applications.
3. In hydronic systems where sediment may exist, install
a strainer in the boiler return piping to prevent large
particles and pipe scale from entering the boiler heat
exchanger. Use a large mesh screen in the strainer.
4. For an existing or new system that uses iron pipe
components install a magnetic filter to capture iron
particulates that will bypass a screen filter.
5. Install this boiler so that the gas ignition system
components are protected from water (dripping,
spraying, etc.) during operation and service (circulator
replacement, condensate trap cleaning, sensor
replacement, etc.).
B. WATER QUALITY
Series PFC
TM
boilers are intended for use in a closed-
loop hydronic system. Make-up fresh water for
the system will include oxygen, calcium and other
substances which may cause corrosion, calcium scale
buildup or other attacks on the hydronic system and
boiler components.
The following steps should be taken to maximize the
longevity of the boiler and system:
1. Water hardness must be between 3 Grains/Gal (gpg)
and 9 Grains/Gal (gpg). Use of a water treatment
system may be required on make-up water in areas
with hard water.
2. The systems water pH level should fall between 7.5
pH and 9.5 pH. The slightly alkaline water will work
to prevent corrosion and neutralize any acidic buildup
over time minimizing potential sources of corrosive
attacks on the heat exchanger.
3. The system should be flushed and cleaned thoroughly
with fresh water and a rinsing agent prior to boiler
installation. Any new system must be cleaned to
remove any flux or welding residue. Any existing
system must be cleaned to remove scale and
particulate matter prior to boiler connection to the
system. Thoroughly flush any cleaning agent from the
system with clean water prior to connecting the boiler.
See Table 4.1 for recommended cleaning agents.
4. High oxygen levels in the system water will allow scale
buildup to occur. Steps must be taken to minimize
4. WATER PIPING & CONTROLS
WATER PIPING & CONTROLS
Failure to properly analyze and treat system water when installing a high efficiency boiler can cause heat
exchanger failure due to water passageway fouling. Black oxide sludge (magnetite – Fe
3
O
4
), red oxide sludge
(iron oxide – Fe
2
O
3
), and calcium scale (limescale) will settle over the hottest portion of the heat exchang-
er coils. This buildup will reduce thermal transfer in the areas where the buildup is greatest resulting in an
increased fouling rate. The high temperatures in these locations will compromise the natural corrosion resis-
tance of the stainless steel material leading to accelerated failure of the heat exchanger.
Failure to address the causes of the fouling in the system can void heat exchanger warranty, and risk property
damage, personal injury or death.
System must be cleaned before the boiler is connected!
- Flush the system with fresh water
- Use a cleaning agent appropriate for the system material and debris to be removed
- Thoroughly flush cleaning agent residue from the system with fresh water
The following actions must be taken after the boiler is connected to the system:
- Treat system water with a corrosion and scale inhibitor to prevent oxidization and scale buildup.
Follow the inhibitor manufacturer’s instructions when treating the system water
WARNING
Maximum Flow Rates and Input
Steel Pipe
Pipe Size
Maximum Flow (GPM)
BTU/HR
1-1/2”
25
220,000
2”
50
450,000
2-1/2”
80
850,000
3”
140
1,300,000
Copper Tubing
Tube Size
Maximum Flow (GPM)
BTU/HR
1-1/2”
22
220,000
2”
45
450,000
2-1/2”
85
850,000
3”
130
1,300,000
Table 4.1: Guide of Maximum Flow Rates for
Different Pipe Sizes with Input
