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The boil out of the boiler and system is neither difficult
nor expensive. The chemicals needed for cleaning
are readily available. Tri-sodium phosphate and
sodium hydroxide (lye) are the most commonly used
chemicals. Be certain the chemicals used contain
NO CHLORIDES. Use only one type of solution in
the system. The amount of chemical required will
vary according to conditions, but one pound per fifty
gallons of water is suggested.
Fill the system with this solution, venting all air. Then,
with the circulating pump running, bring the system
to design or operating temperature. After circulating
water for two to three hours, the system should be
drained completely, and refilled with fresh, softened
water. Usually enough of the cleaning solution will
adhere to the piping to result in an alkaline solution
satisfactory for operation. A pH reading between,
8.3 – 10.5 is preferred. If necessary, to increase the
pH, a small amount of cleaner may be added.
C. Replacement Boiler Installations
Clean or replace all system piping and heating units.
Arrange for chemical or mechanical cleaning of the
entire system. A chemical treatment company should
be consulted for the proper means of any chemical
cleaning. Replace any piping that is deteriorated
beyond safe or cleanable condition.
Flush the system clean, being certain to isolate the
boiler.
WARNING
WARNING
Do not flush the system through the boiler.
For some old systems, there is a reluctance to clean
the piping because of possible leaks occurring in badly
corroded lines. Should the customer refuse cleaning,
it is necessary to install filtration equipment. Install
either a fibrous filter or a centrifugal filter in the boiler
return piping. This will collect and remove sediment
from the system. A booster pump may be required to
overcome the additional pressure drop introduced in
the line by the filter. When filling the system, provide
chemical treatment as outlined in section "E. Boiler
Water Treatment".
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Thermal Solutions, 1175 Manheim Pike, Lancaster, PA 17601 Website: www.thermalsolutions.com
Phone: 717-239-7642 Fax: 877-501-5212 Email: sales@thermalsolutions.com
Failure to properly clean the system or to install
mechanical sediment removal equipment can result
in tube blockage and severe corrosion plus damage
to pumps, controls, and air removal devices.
Inspect, repair as necessary, or replace system air
control devices.
Install gauge glasses on air expansion tanks and install
a tank fitting in the system connection to the tank.
Install a strainer in the boiler return piping.
D. Draining and refilling the boiler & system
If the system is drained and then refilled, chemical
treatment is essential to treat the raw water. Use
only clean, softened water.
WARNING
WARNING
Use only clean, softened, and treated water.
Chemical treatment of the raw water is essential
when filling or refilling the system
1. Hydrostatic Test of Boilers and System
a. After completing the boiler and burner
installation, the boiler connections, fittings,
attachments and adjacent piping must be
inspected for leaks by filling the unit with
water. The pressure should be gradually
increased to a pressure just below the setting
of boiler safety relief valve(s).
b. Remove the boiler tube access panels (see
dimensional drawing in the boiler manual).
Inspect the tube to header joints to be
certain that all tube fittings are sealed. This
is necessary because, although the boiler is
hydrostatically tested at the factory, minor
leaks in fittings and at attachments can
develop from shipping vibration or from
installation procedures. Replace tube access
panels before proceeding to start boiler
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