Good housekeeping practices help maintain a professional appearing boiler room. Only trained and authorized personnel should be permitted to operate, adjust, or repair the boiler and related equipment. The boiler room should be kept free of all material a
Even though the boiler has electrical and mechanical devices that make it automatic or semiautomatic in operation, the devices require systematic and periodic maintenance. Any “automatic” feature does not relieve the operator from responsibility. Automati
Alertness in recognizing an unusual noise, improper gauge reading, leaks, etc., can make the operator aware of a developing malfunction, permitting prompt corrective action that may prevent extensive repairs or unexpected downtime. Any leaks - fuel, water
Preventive maintenance measures such as regularly checking the tightness of connections, locknuts, setscrews, packing glands, etc., should be included in regular maintenance activities.
Insurance regulations or local codes may require a periodic inspection of the pressure vessel by an authorized inspector. Inspections are usually scheduled for periods of normal boiler downtime such as during an off season. The major inspection can often
While the inspection pertains primarily to the waterside and fireside surfaces of the pressure vessel, it provides the operator with an excellent opportunity to perform a detailed check of all components of the boiler, including piping, valves, pumps, gas
Replacement spare parts, if not on hand, should be ordered well in advance of a shutdown.
Cleaver-Brooks boilers are designed, engineered and built to give long life and excellent service. Good operating practices and consistent maintenance and care will promote efficiency and economy of operation and contribute to many years of reliable perfo
Cleaver-Brooks offers a Planned Maintenance Program that covers many of the items included on this chapter. For more information on the Planned Maintenance Program, contact your local Cleaver-Brooks authorized representative.
Soot and other noncombustible deposits are effective insulators and, if allowed to accumulate on boiler heat exchanger surfaces, will reduce heat transfer to the water and increase fuel consumption. Soot and other deposits can absorb moisture and may attr
Inspection and cleanout should be performed at frequent intervals, depending upon the boiler's load, type and quality of fuel, internal boiler temperature, and combustion efficiency. Stack temperature can be used as a guide to determine cleanout intervals
Access to the furnace for tube and refractory cleaning is provided through a hinged burner door at the front of the boiler. When opening the burner door, first shut off the electrical and fuel supplies and then disconnect all fuel lines at the burner watc
Tubes should be brushed with a wire brush to remove any soot or other accumulations. Refractory surfaces should be cleaned, if necessary, with a soft bristle brush. Loose material should be vacuumed from the bottom of the furnace.
Upper pass access is gained through removal of the inner and outer side casing.
To remove the outer casing panels, first disconnect and remove any electrical conduit, boxes and brackets attached to the side outer casing.
Match mark the outer panels for repositioning.
Remove screw (if installed) from frame above each outer panel. Starting with center panel, slide panel up, swing bottom of panel away from boiler and then slide down from the upper frame and set panel aside. After the center panel(s) are removed, the end
It there are only two outer panels (Models 150 through 350), then slide one end panel further into the corner frame to allow the other panel to slide free from the corner frame. If obstructions are present, such as the gas train, there may not be enough r
Match mark all inner casing panels for repositioning later. Inner casing panels must be removed in sequence starting from either end.
Remove nuts, washers and clamp angles from the end and bottom of panels. Remove nuts, washers and bolt bars from vertical seams.
Loosen nuts on top clamp angles but don't remove until panel is ready to be removed. Inner casing panels can not be removed by pulling panel straight out from boiler because of a 1" gasket retaining strip that overlaps behind the panels.
Remove inner casing panels by sliding or angling panel away from remaining panels until the 1" retaining strip has cleared panel and then panel can be removed and set aside.
After removing the inner side casing, the pass cover plates (2nd pass only) must be removed. The cover plates are screwed together and are held in place by tabs inserted between the tubes.
Remove the insulation by starting at one end and carefully rolling it up. The insulation blocks can now be removed from the pass opening. Keep the insulation blocks in order once they have been removed so they can be re-installed in the same position. In
Now that the 2nd (left side) and 4th (right side) pass openings are exposed, cleaning can be done in the same way as the furnace area. Since the 3rd pass is only open on the ends, cleaning is done by pushing a wire brush mounted on a long handle, through
The fifth pass is cleaned from above the tubes. As in the furnace, loose material should be removed by vacuuming after brushing. The pressure vessel should be inspected for any signs of deterioration after cleaning.
The flue outlet and stack should also be inspected annually and cleaned as necessary. Commercial firms are available to perform this work. The stack should also be inspected for damage and repaired as required.
Once everything has been cleaned and inspected the boiler can be put back together. Install insulation blocks in the 2nd and 4th pass openings in their previous positions. Spray adhesive on tubes above and below pass opening and install blanket insulation
Prior to installing the inner casing, inspect studs on boiler and bolt bars for any thread damage. Any damaged threads should be cleaned and chased with a 3/8"-16 die. Apply a small amount of Cleaver-Brooks "Never-Seez" (p.n. 797- 1814 or 797-1816) on eac
Before the inner casing can be installed, the old gaskets must be removed from the panels and around the perimeter of the boiler and replaced with new ones.
After removing the gaskets, the surfaces should be cleaned to allow the new gasket to seal properly.
The gasket around the perimeter of the boiler should be one piece with the ends overlapping side by side somewhere along the upper (roof) surface. A small amount of silicone will be required to fill gaps and valleys where the gasket crosses.
This includes the roof to end wall seams and the base angle to end wall gaps. It is important that the entire gap between the end wall and the base angle be completely sealed.
The seal along the base of the end wall should also be checked and resealed if necessary. The gasket should be positioned to the inside of the studs with a 1/4" gap between the studs and the gasket.
Install gasket on side casing panels so it extends past the top and bottom by 1/4" or more and 1/16" to 1/8" out the back at the top and bottom of the panel. (See Figure 7-1).
Starting from one end, set panel edge 1/8" to 1/4" from the studs on the end wall. Install the first lower clamp angle over the respective studs, install washers and start nuts. Any nuts that are difficult to install should be replaced.
Place the upper clamp angle over the top studs and install washers and nuts but don't tighten.
The end clamp can now be installed and nuts on the end clamp can be snugged up but not completely tightened.
Before installing the next panel, apply a small amount of teflon paste to the area where the vertical gasket and the horizontal gaskets will overlap at the top and bottom.
This will help ensure an air tight seal. Install the next panel in line being careful to slide the 1" gasket retaining strip behind the panel but under the insulation.
Install the next panel in line being careful to slide the 1" gasket retaining strip behind the panel but under the insulation.
Install the bottom and top clamp angles to hold panel in place, but don't tighten.
Install the bolt strips, washers and nuts which clamp the panels together.
Pull panels together evenly and tighten nuts to 250 to 300 in-lbs.
Repeat until all panels are installed and securely bolted together. Now panels can be evenly pulled toward boiler with clamp angles. Tighten all nuts to 250 to 300 in-lbs.
The outer casing panels can now be installed starting with the end panels.
Slide each end panel under the upper frame and push the bottom section into the boiler and allowing it to slide down to catch the bottom clamp angle.
Then slide the end panels under the corner frames and install any remaining center panels.
The fireside should be thoroughly cleaned prior to any extended layup of the boiler.
Depending upon circumstances, a protective coating may be required. See Chapter 3, Section H "Preparation for Extended Layup".
The relief valve is a very important safety device and deserves attention accordingly.
Proper removal, installation or handling of a relief valve is of primary importance.
Exercise care when removing, installing or handling a relief valve to ensure proper operation, long service life, and to ensure that the valve functions as designed.
Use only flat jawed wrenches on the flats of the valve
Do not use a pipe threaded into the outlet to turn a valve
Apply only a moderate amount of pipe compound to male threads
Avoid over tightening, which can distort valve seating surfaces
Do not paint, oil or otherwise cover any interior or working parts of the valve. A relief valve does not require any lubrication or protective coating to work properly.
Discharge piping must be properly arranged and supported so that its weight does not bear on the relief valve.
Handle with care a valve that has been removed from the boiler. A dropped valve should be considered as damaged until it has been inspected and passed by the valve manufacturer's authorized representative.
Relief valves should be operated only often enough to assure that they are in good working order.
Follow the recommendations of your boiler inspector regarding valve inspection and testing. The frequency and method of testing should be based on the recommendation of your boiler inspector and/or the valve manufacturer, and should be in accordance with
Most instances of major boiler damage result from operating with low water. Since low water cutoff devices are set by the original manufacturer, no attempt should be made to adjust these controls in order to alter the point of low water cutoff.
If a low water cutoff should become erratic in operation, immediately replace it or contact your local Cleaver-Brooks authorized representative for assistance.
It is essential to verify proper operation of low water cutoff devices as frequently as possible. However, it is impractical to perform daily and monthly maintenance on some models of the low water cutoff devices on a hot water boiler.
Hot water systems are fully closed. Daily or monthly maintenance on some models of the low water cutoff devices would involve draining the entire water content of the system and would require makeup and additional feedwater treatment that might not otherw
To verify the proper operation of float style low water cutoff devices, the system must be drained.
Remove the operating mechanism from the bowl and check and clean the float ball, internal moving parts, and the bowl housing. Also, check the cross-connecting piping to make certain that it is clean and free of obstruction.
It is impractical to blowdown the low water cutoff devices on a hot water boiler, since the entire water content of the system would become involved.
Many hot water systems are fully closed and any loss of water will require makeup and additional feedwater treatment that might not otherwise be necessary.
Since the boiler and system arrangement usually make it impractical to perform daily and monthly maintenance of the low water cutoff devices, it is essential to remove the operating mechanism from the bowl annually or more frequently, if possible, to chec
If test-n-check valves are installed on the float style low water cutoff devices, these controls can be tested by opening the blow down valve. The test-n-check valves restrict water flow when the blow down valve is open allowing water to drain from the co
The test-n-check valves permit testing of the control without draining the entire system therefore allowing regularly scheduled verification of float style low water cutoff.
The need to periodically check water level controls and the waterside of the pressure vessel cannot be overemphasized.
Most instances of major boiler damage are the result of operating with low water or the use of untreated (or incorrectly treated) water.
Always be sure of the boiler water level. The water column should be blown down routinely.
Check samples of boiler water and condensate in accordance with procedures recommended by your water consultant. Refer to sections E and I in Chapter 3 for blowdown instructions and internal inspection procedures.
A typical water level control is mounted in the water column and has float actuated mercury switches. One switch is connected to the burner limit circuit and will stop the burner if a low water condition occurs.
The other switch is connected to the feedwater circuit to energize a water pump or feeder valve to maintain water at the proper operating level.
Usually, the control is of the automatic reset type and will remake the limit circuit when the water level is restored. Some applications require that a control be equipped with a manual reset mechanism that must be manually reset before the burner can be
Since low water cutoff devices are generally set by the original manufacturer, no attempt should be made to adjust these controls to alter the point of low water cutoff or point of pump cut-in or cut-out.
If a low water device should become erratic in operation or if its setting changes from previous established levels, check for reasons and correct: Repair or replace as required.
These controls normally function for long periods of time, which may lead to laxity in testing on the assumption that normal operation will continue indefinitely.
The controls' operation may be checked by stopping the water supply to the boiler while the burner is operating at low fire. While under constant attendance, allow the water level to drop at a normal rate.
Check for proper operation of the feedwater controller and the low water cutoffs.
Do not restart until all cross-connecting piping is checked for obstructions. Also check the float bowl. If these are clean, repair or replace the control. Repeat the above test to ensure proper operation prior to returning the boiler to service.
On a steam boiler, the head mechanism of the low water cutoff device(s) should be removed from the bowl at least once a month to check and clean the float ball, the internal moving parts, and the bowl or water column.
Remove the pipe plugs from the tees or crosses and make certain the cross- connecting piping is clean and free of obstructions.
Controls must be mounted in a plumb position for proper performance. Determine that piping is vertically aligned after shipment and installation and throughout the life of the equipment. A scheduled blowdown of the water controls on a steam boiler should
A broken or discolored glass must be replaced at once. Periodic replacement should be a part of the maintenance program. Always use new gaskets when replacing a glass. Use a proper size rubber packing.
Do not use “loose packing,” which could be forced below the glass and possibly plug the valve opening
Close the valves when replacing the glass. Slip a packing nut, a packing washer, and packing ring onto each end of the glass.
Insert one end of the glass into the upper gauge valve body far enough to allow the lower end to be dropped into the lower body. Slide the packing nuts onto each valve and tighten.
If the glass is replaced while the boiler is in service, open the blowdown and slowly bring the glass to operating temperature by cracking the gauge valves slightly. After glass is warmed up, close the blowdown valve and open the gauge valves completely.
Check trycocks and gauge cocks for freedom of operation and clean as required
It is imperative that the gauge cocks are mounted in exact alignment. If they are not, the glass will be strained and may fail prematurely.
A blowdown cock is provided on the lower gauge glass fitting and a daily blowdown is recommended.
The operating controls should be inspected monthly. Examine the tightness of electrical connections and keep the controls clean.
Remove any dust that accumulates on the interior of the controls using low pressure air that is free of moisture and oil. Take care not to damage the mechanism.
Examine any mercury tube switches for damage or cracks. Dark scum over the normally bright surface of the mercury indicates a damaged tube that may lead to erratic switching action.
Make certain that controls are correctly leveled. Covers should remain on controls and panels at all times.
Dust and dirt can cause excessive wear or overheating of the motor stator and the relay contacts, and affect operation of other controls.
The power supply to the boiler must be protected with dual element fuses (fusetrons) or circuit breakers. Similar fuses should be used in branch circuits. Standard one-shot fuses are not recommended
This control requires minimal maintenance because the safety and logic sections are integral and inaccessible, with no accessible contacts.
Regularly check to see that the retaining screws holding the chassis to the mounting base are secure, and that the amplifier and the program module are securely inserted.
It is recommended that a spare control be kept on hand and service be rotated between the active and the spare control (programmer).
Your spare control should be wrapped in plastic and stored in a dry atmosphere.
During an extended shutdown (for example, a seasonal shutdown), the active control should be removed and stored in a dry atmosphere. Moisture can cause problems with control operation
The flame detector lens should be cleaned as often as operating conditions demand. Use a soft cloth moistened with detergent to clean the lens.
A safety check procedure should be established to test the complete flame safeguard system at least once a month.
Tests should verify safety shutdown and a safety lockout upon failure to ignite the main flame and upon loss of flame. Each of these conditions should be checked on a scheduled basis.
Refer to the burner manual for information regarding tests of the flame safeguard system. Contact your local CleaverBrooks authorized representative for assistance, if required.
With the burner in normal operation at the low fire rate, shut off the main burner fuel valve to interrupt the fuel supply and extinguish the main flame.
The relay must signal the loss of flame, resulting in the fuel valve(s) being deenergized.
The control will lock out on a safety shutdown. The flame failure light (and optional alarm) will be activated. The blower motor will stop.
Turn the burner switch off. Reset the safety switch. Reestablish the main fuel supply
Refer to the burner sections for specific information regarding operation and maintenance of the burner.
Oil strainers should be serviced frequently in order to maintain a free and full flow of fuel to the burner
Installation of a vacuum gauge in the burner supply line between the burner oil pump and the strainer is strongly recommended.
Regular observation and recording of the gauge indication will assist in determining when the strainer needs servicing.
The fuel oil strainer element must be removed and cleaned or replaced at regular intervals, or when a rising trend in the burner supply pump suction indicates blockage.
When servicing the strainer, fuel supply and return line valves should be shut off. The strainer should be drained of oil and any sediment collected at the bottom of the canister.
Remove the cover and withdraw the strainer element.
Replaceable elements should be disposed of properly.
Reusable elements may be cleaned by immersing them in solvent until attached deposits have been loosened, and then shaking them dry
Reassemble the strainer, taking care to seal the canister properly to avoid air infiltration and resulting loss of suction. Open the fuel supply and the return line valves.
Refer to the burner sections for specific information regarding operation and maintenance of the burner. The motorized gas valve requires little maintenance, as the operating mechanism is immersed in oil and completely sealed. However, proper operation sh
Keep the outer parts of the valve(s) clean, especially the stem between the operator and the valve. A nicked, scored, or otherwise damaged valve stem can cause leakage. Do not remove dust covers if installed.
The stem packing gland is the O-ring type. If oil is noticed around the operator base, or if leakage occurs, the valve must be repaired. If the actuator is sluggish or fails to operate, and the oil level is known to be correct, the operator portion should
Foreign matter between the valve seat and the seat disc will cause leakage.
Valves are readily disassembled; however, care must be taken to see that internal parts are not damaged during removal and that reassembly is in the proper order.
A low hum or buzzing will normally be audible when the solenoid coil is energized. If the valve emits a loud buzzing or a chattering noise, check for proper voltage.
If voltage is correct, clean the plunger assembly and interior plunger tube thoroughly. Do not use any oil.
Make sure that the plunger tube and solenoid are tight when assembled. Take care not to nick, dent, or damage the plunger tube.
Solenoid coils can be replaced without removing the valve from the line
Check the coil position and make sure that any insulating washers or retaining springs are reinstalled in the proper order.
The boiler is shipped with completely installed refractory. High temperature refractory lines the burner door and floor of the boiler.
Front and rear walls, side casing panels, the roof section, the bottom drum and the drum vent are protected with high temperature insulation. Preventive maintenance through periodic inspection will keep the operator aware of the condition of the refracto
The most obvious indication of a problem is the appearance of discolored paint on the casing or soot and hot gases escaping at seal joints. It is important that at start-up any problems are noted and corrected before the boiler is put back into operation.
Inspect the area around the door and look for discolored paint or evidence of combustion gas leakage. If a problem is noted or the door is being opened for scheduled maintenance look for warped sealing surfaces and make sure that the insulation on the fro
Cracks may appear in the burner door refractory as a result of expansion and contraction from operation. If cracks are larger than 1/8” when the refractory is cooled, the cracks should be filled with a high temperature bonding airdry mortar such as Cleave
Access to the boiler furnace area is gained through the burner door opening at the front of the boiler. Whenever the burner is opened, the gasket and gasket surfaces of the burner door should be inspected.
A good seal between the burner door and the boiler is necessary to prevent leakage of combustion gases and loss of efficiency. Combustion gas leaks can cause hot spots with subsequent damage to the burner door and surrounding refractory.
Damaged or hardened gaskets must be replaced before the burner is put back in operation.
If a new gasket is necessary, remove the old gasket and clean the gasket surface on the wall and burner door. A spray adhesive is used to hold the rope gasket in place around the burner opening.
A high temperature silicone may be needed to seal under the rope gasket at the wall seams. The rope gasket should wrap around the opening at least two times
Before the burner door is closed, inspect studs and clean threads if necessary with 1/2"-13 die.
Apply a small amount of Cleaver-Brooks "Never-Seez" (p.n. 797-1814 or 797- 1816) to the studs. Any nuts that are difficult to thread on studs should be replaced. Door fasteners should be run in and tightened evenly to avoid distorting the door or damagin
Start tightening at the top and proceed around the door, alternately tightening opposite fasteners until all are snug.
After the boiler is back in operation, check for gas leaks around the door opening, and retighten the fasteners as required to provide a gas-tight seal.
Inspect the areas around the drum seals and look for soot or hot gas leaks. If a problem is noted look for the source of the leak.
Remove the old insulation and sealant from around the drum. Using a pumpable insulation material (p.n. 872-680), fill the void flush with the outside of the wall. Allow the area to set up and apply a thick bead of high temperature silicone around the dru
Inspect the area around the sight port for paint discoloration. A hot spot around the rear sight port is caused by either a poor seal between the sight port insulator and the wall, a cracked insulator or a flue gas leak at the sight port cap.
Check the threads of the cap and sight tube. If necessary, clean the threads and/or replace the cap. If the screws that hold the sight glass retainer in place are leaking tighten the screws or replace the cap.