Assessments - 2, GPA: 5
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Facilidade de uso
There may be many possible causes of leaks in oil lines such as: 20 i. Fitting leaks due to misflared tubing or damaged fitting. ii. Fuel line leak due to crushed or bent tubing. iii. Filter connection leaks. iv. Tank connection leaks. The following actions can eliminate air leaks: i. Bleed pump as detailed in System Start-Up Section of this manual. ii. Replace flare fittings. iii. Replace oil supply line. iv. Repair oil filter leaks v. Replace or repair tank fittings. e. GASKET LEAKS— If 11.5% to 12.5% CO2 with a #1 smoke cannot be obtained in stack, look for air leaks around the canopy seal. Such air leaks will cause a lower CO2 reading in the stack. The smaller the firing rate the greater effect an air leak can have on CO2 readings. f. DIRT— A fuel filter is a good investment. Accidental accumulation of dirt in the fuel system can clog the nozzle strainer and produce a poor spray pattern from the nozzle. g. WATER— Water in the fuel, in large amounts, will stall the fuel pump. Water in the fuel pump, in smaller amounts, will cause excessive wear on the pump, but more importantly water does not burn. It chills the flame, causes smoke, and allows unburned fuel to pass through the combustion chamber and clog the flueways of the boiler. h. COLD OIL— If the oil temperature approaching the fuel pump is 40°F or lower, poor combustion or delayed ignition may result. Cold oil is harder to atomize at the nozzle. Thus, the spray droplets get larger and the flame shape gets longer. An outside fuel tank that is above grade or has fuel lines buried in the ground above the frost line is a good candidate for cold oil. The best solution is to place the tank and oil lines in the ground below the frost line. i. HIGH ALTITUDE INSTALLATIONS Typically, the rule to use for high altitudes is to increase the air supply by 4% per each 1000 ft. above 2000 ft. altitude from sea level. This means that the air setting will have to be higher than the calibration marks in proportion to the altitude. Use instruments and set for 11.5 to 12.5% CO2. j. START-UP NOISE — Late ignition is the cause of start-up noises. If it occurs recheck for electrode settings, flame shape, air or water in the fuel lines. k. SHUT DOWN NOISE — If the flame runs out of air before it runs out of fuel, an after burn with noise may occur. That may be the result of a faulty cut-off valve in the fuel pump, or it may be air trapped in the nozzle line. It may take several firing cycles for that air to be fully vented through the nozzle. Water in the fuel or poor flame shape can also cause shut down noises. P. TEST CONTROLS 1. CHECK THERMOSTAT OPERATION. Raise and lower thermostat setting as required to start and stop burner. 2. VERIFY PRIMARY CONTROL SAFETY FEATURES using procedures outlined in Instructions furnished with control (See back of Control Cover) or Instructions as follows: a. Simulate flame failure: • Follow the starting procedure to turn on the burner. • Close the hand valve in the oil supply line. • Safety switch should lock out in approximately 15 seconds. Ignition should stop and oil valve should close. Blower will stop after postpurge period. 21 • Push red reset button to reset safety switch. b. Simulate ignition failure: • Follow the starting procedure to turn on the burner, but do not open the oil supply hand valve. • Safety switch should lock out in approximately 15 seconds. Ignition and motor should stop and oil valve should close. • Push red reset button to reset safety switch. c. Simulate power failure: • Follow the starting procedure to turn on the burner. • With the burner running, turn off the power to the system by tripping the circuit breaker or removing the fuse. • Burner should stop. • Restore power. Burner should start. 3. VERIFY HIGH LIMIT OPERATION. a. Adjust thermostat to highest setting. b. Observe temperature gauge. When temperature is indicated, adjust limit to setting below observed temperature. Burner should stop. c. Adjust limit to setting above observed temperature. Burner should start. d. Adjust thermostat to lowest setting. Adjust limit to desired setting. 4. CHECK LOW WATER CUTOFF (if so equipped). a. Adjust thermostat to highest setting. b. With boiler operating, open drain valve and slowly drain boiler. c. Burner should stop when water level drops below low water cutoff probe. Verify limit, thermostat or other controls have not shut off boiler. d. Adjust thermostat to lowest setting. Refill boiler. Q. FREQUENT WATER ADDITION A leaky system will increase the volume of make-up water supplied to the boiler which can significantly shorten the life of the boiler. Entrained in make-up water are dissolved minerals and oxygen. When the fresh, cool make-up water is heated in the boiler the minerals fall out as sediment and the oxygen escapes as a gas. Both can result in reduced boiler life. The accumulation of sediment can eventually isolate the water from contacting the steel. When this happens the steel in that area gets extremel...