Improper Combustion; Actuation Of Protective Devices - Hyundai HDFN-80-1400 Operation Instructions Manual

10.3 Improper Combustion

Fuel flow rate is excessively high or low  Adjust fuel control valve and air damper opening
Gas supply pressure fluctuates
(for gas-fired unit)
Air-fuel ratio is improper
Pressure loss
excessively high
Pressure loss
excessively low (excessive draft force)
Note: Only skilled service engineers are allowed to do above mentioned adjustment works for safety.

10.4 Actuation of Protective Devices

Protective Devices
Chilled water flow rate differential
pressure switch (U3)
Chilled water
Temperature low switch (U6)
High pressure generator pressure
switch (U7)
High pressure
temperature switch (u8)
High pressure generator level
Switch (low) (U9)
Exhaust gas temperature switch
(Y2)
Gas pressure switch (Y1)
(applied for gas fired type)
Over-current relay for
Canned pump motor
Cause
of smoke duct
of smoke duct
Cause
 Reduction of chilled water flow
rate
 Chilled water load is too small
 Chilled water temperature is too
low
 Drop of degree of vacuum
 Rise of cooling water inlet
generator temperature
 Shortage of cooling water flow
rate
 Dirty cooling water tubes
 Shortage of solution circulating
flow rate
 Operation error of electrodes
 Too much flow rate of fuel
 Dirty heat transfer tubes
 Gas pressure drop of the forced
fan
( Failed governor
( Over load of motor
( Crystallization
 Check and adjust fuel supply pressure
 Adjust gas supply pressure
 Check fuel and air ratio
 Adjust fuel control valve and air damper opening
 Measure the draft force and modify the shape and size
is
of the smoke duct
 Measure the draft force and install a damper in the
is
smoke duct
58
Steps to be Taken
Steps to be Taken
 Check chilled water pump
 Chilled/hot water system
 Check the setting point of chilled
water thermostat and chilled
water controller
 Check the chilled water flow rate
As mentioned before
 Adjust solution circulating flow
rate
 Replace with new electrodes
 Set fuel flow rate to the rating
 Check fuel supply pressure
 Clean heat transfer tubes
 Adjust air-fuel ratio
( Check the forced fan
( Check air inlet
(Check duct leakage and repair it
( Check and replace with new
igniter transformer
( De-crystallize (See 5.8)