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010.4150.0720 08.21
7. STARTUP AND CONFIGURATION
7.1 GENERAL
During the initial startup and before combustion heat can be
applied to the exchanger, ensure that liquid is flowing through
the economizer.
NOTE: ENERVEX recommends that liquid is flowing
through the economizer at all times to avoid damage
to the heat module(s) from stack exhaust overheat.
Upon cold startup of a full boiler, provisions must be
made to ensure water flow through the VHX-DR. Assure
sufficient flow to prevent any unwarranted temperature
and pressure buildup within the liquid side of the heat
module. When the boiler reaches the operating steam
pressure of the system and begins to take on feedwater,
normal operation can resume.
! Important
If liquid is introduced into a hot exchanger, severe
damage can result and will void any warranty. Contact
ENERVEX for applications where the exchanger is
requested to run dry.
If the final exhaust temperatures are too low, pressure drop
across the economizer is too high, or if the desired water
temperature is exceeded, adjust the gas bypass damper to
attain the desired objective.
While the exchanger is in a clean, like-new condition, note
and record the following at a specified condition:
• Liquid inlet and outlet temperatures
• Exhaust gas inlet and outlet temperatures
• Pressure gauge reading (if applicable)
This information will provide a point of reference in the event
of a future fouling condition.
MONITORING PERFORMANCE
It is recommended to inspect the core or coil if the
performance (liquid temperatures leaving and Btu/
hr. recovery) begins to decrease. A good practice of
maintenance is to keep a performance schedule starting
when the economizer is installed to compare with any future
changes.
Operational start-up
Make sure that:
If there is a risk of high temperatures, the unit is insulated as
a precaution to avoid injuries.
Installation has been carried out according to the flow
schedule / drawing and recommendations.
• Connections are tight.
• No vibrations or pulsations are transferred to the Cross
30.
• The liquid side is filled and deaerated.
• The flow rate and pressure on the liquid side are correct
before gas flow is started.
• The temperature and flow rates are according to
specification.
• There is appropriate drainage to deal with any
condensation.
NOTE: Ensure that the combustion source is off
and is cool, and the economizer is cool before
attempting to inspect or clean the coil(s).
