Boiler Installation by pengxiang

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									Boiler Installation
 Hot water heating  Water heaters  Power

Colorado Revised Statutes
9-4-117 - New heating boilers and hot-water supply boilers installations. No heating boiler or hot-water supply boiler, except those exempt by this article, shall be installed in this state unless it has been constructed, inspected, and stamped in conformity with the rules for construction of low-pressure heating boilers of the A.S.M.E. boiler and pressure vessel code and is approved, registered, and inspected in accordance with the requirements of this article

Rules
Section 1-8 Applicability of ASME CSD-1 ASME CSD-1 applies to all boilers and pressure vessels installed, re-located or returned to service on or after January 1, 1993. The pertinent edition of ASME CSD-1 is the one adopted by the Colorado Boiler and Pressure Vessel Code at the installation, re-location, or return to service date.

Hot Water Heating

“H”
CERT. By

Nameplate

Nameplate
(1) The shop assembler's name preceded by the words "Certified by" (2) Maximum allowable working pressure;
(3) Safety or safety relief valve capacity (minimum), lb/hr or MBH, as determined according to HG-400.1(e) and HG-400.2(d);

(NB) 000000

Section 1-15 Registration Requirements
(4) Maximum water temperature. (a) All boilers, including reinstalled and second hand, regardless of code of construction, shall be registered with the National Board of Boiler and Pressure Vessel Inspectors (excluding cast iron boilers and non-standard boilers).

Safety & Safety Relief Valves
(1) Each hot water heating or supply boiler shall have at least one officially rated safety relief valve of the automatic reseating type, identified with the "V“ or "HV" symbol, and set to relieve at or below the maximum allowable working pressure of the boiler.

(2) Hot water heating or supply boilers limited to a water temperature not in excess
of 210°F (99°C) may have, in lieu of the valve(s) specified in (1) above, one or more officially rated temperature and pressure safety relief valves of the automatic reseating type identified with the "HV" symbol, and set to relieve at or below the maximum allowable working pressure of the boiler.

Safety & Safety Relief Valves
Permissible Mounting. Safety valves and safety relief valves shall be located in the top or side of the boiler. They shall be connected directly to a tapped or flanged opening in the boiler, to a fitting connected to the boiler by a short nipple. to a Y-base. or to a valveless header connecting steam or water outlets on the same boiler. Coil or header type boilers shall have the safety valve or safety relief valve located on the steam or hot water outlet end. Safety valves and safety relief valves shall be installed with their spindles vertical. The opening or connection between the boiler and any safety valve or safety relief valve shall have at least the area of the valve inlet.

Safety & Safety Relief Valves continued
(c) when more than one safety relief valve is used on either hot water heating or hot water supply boilers, the additional valves shall be officially rated and may have a set pressure within a range not to exceed 6 psi (42 kPa) above the maximum allowable working pressure of the boiler up to and including 60 psi (414 kPa), and 5% for those having a maximum allowable working pressure exceeding 60 psi (414 kPa).

(e) The required steam relieving capacity, in pounds per hour, of the pressure relieving
device or devices on a boiler shall be the greater of that determined by dividing the maximum output in Btu at the boiler nozzle obtained by the firing of any fuel for which the unit is installed by 1000, or shall be determined on the basis of pounds of steam generated per hour per square foot of boiler heating surface as given in Table HG400.1. For cast iron boilers constructed to the requirements of Part HC, the minimum valve capacity shall be determined by the maximum output method. In many cases a greater relieving capacity of valves will have to be provided than the minimum specified by these rules. In every case, the requirements of HG-400.2(g) shall be met.

Table HG-400.1

More S.V. & S.R.V.’s
(a) A discharge pipe shall be used. Its internal cross-sectional area shall be not less than the full area of the valve outlet or of the total of the valve outlets discharging thereinto and shall be as short and straight as possible and so arranged as to avoid undue stress on the valve or valves. A union may be installed in the discharge piping close to the valve outlet. When an elbow is placed on a safety or safety relief valve discharge pipe, it shall be located close to the valve outlet downstream of the union.

And still more S.V. & S.R.V.’s
(b) The discharge from safety or safety relief valves shall be so arranged that there will be no danger of scalding attendants. The safety or safety relief valve discharge shall be piped away from the boiler to the point of discharge, and there shall be provisions made for properly draining the piping. The size and arrangement of discharge piping shall be independent of other discharge piping and shall be such that any pressure that may exist or develop will not reduce the relieving capacity of the relieving devices below that required to protect the boiler.

Bonus Question?
Finish this line.

He who lives by the sword….. Shall be shot by those who do not.

Low Water Fuel Cutoff “ LWCO”
CW-130 Requirements for Water Level Controls for HotWater Heating Boilers. (a) Each automatically fired hot-water heating boiler, except those installed in residences (as de-fined by the authority having jurisdiction), shall be protected by a lowwater fuel cutoff intended for hot water service (see also CW-210). Lets continue…..

LWCO cont…..
(c) If the low-water fuel cutoff is located in the system piping, it must be assured that the float chamber will drain properly under a low-water condition; and the installation must be arranged to assure that if flow occurs in the float chamber, it will be in the upward direction. (d) Functioning of the low-water fuel cutoff due to a lowwater condition shall cause a safety shut-down (lockout) requiring manual reset. Where a reset device is separate or remote from the low-water cutoff, a means shall be provided to indicate actuation of the low-water cutoff. The manual reset device may be the instantaneous type, or may include a time delay of not more than 3 min after the fuel has been cut off.

More LWCO……
(e) A means shall be provided for testing the operation of the low-water cutoff without resorting to draining the entire system. Such means shall not render the device inoperable.

Lets not forget the Flow Sensing Device
(a) In lieu of the requirements for low-water cutoffs in CW100, a water tube or coil-type boiler, requiring forced circulation to prevent overheating and failure of the tubes or coils, shall have an accepted device to prevent burner operation at a flow rate inadequate to protect the boiler unit against over-heating. (b) When there is a definitive waterline, a low-water fuel cutoff as required in CW-100 shall be provided in addition to the sensing device required in the preceding paragraph.

Temperature Controls CSD-1
(b) Each automatically fired hot-water boiler or each system of commonly connected hot-water boilers shall have at least one temperature-actuated control to shut off the fuel supply when the system water reaches a preset operating temperature. This requirement does not preclude the use of additional operating control devices where required.

(c) In addition to the temperature control required in (b) above, each individual automatically fired hot-water boiler unit shall have a high temperature limit control that will prevent the water temperature from exceeding the maximum allowable temperature. Functioning of this control shall cause a shutdown (lockout) requiring manual reset. The manual reset may be incorporated in the temperature limit control or may be effected remotely. Where a reset device is separate or remote from the temperature limit control, a means shall be provided to indicate actuation of the temperature limit control. Each limit and operating control shall have its own sensing element and operating switch.

Temperature Controls Section IV
Each automatically fired hot water heating or hot water supply boiler shall be protected from over-temperature by two temperature-operated controls.

(a) Each individual automatically fired hot water heating or hot water supply boiler shall have a safety limit control that will cut off the fuel supply to prevent water temperature from exceeding the maximum allowable temperature of 250°F at the boiler outlet. This water temperature safety control shall be constructed to prevent a temperature setting above 250°F. (b) Each individual hot water heating or hot water supply boiler or each system of commonly connected boilers without intervening valves shall have a control that will cut off the fuel supply when the water temperature reaches an operating limit, which shall be less than the maximum allowable temperature.

Pressure Gage
(a) Each hot water heating or hot water supply boiler shall have a pressure or altitude gage connected to it or to its flow connection in such a manner that it can not be shut off from the boiler except by a cock with tee or lever handle. placed on the pipe near the gage. The handle of the cock shall be parallel to the pipe in which it is located when the cock is open. (b) The scale on the dial of the pressure or altitude gage shall be graduated approximately to not less than 1 1/2 nor more than three times the pressure at which the safety relief valve is set.

(c) Piping or tubing for pressure or altitude-gage connections shall be of nonferrous metal when smaller than 1 in. pipe size.

Modular Boiler
HG-716 MODULAR BOILERS (a) Individual Modules (1) The individual modules shall comply with all the requirements of Pant HG, except as specified in HG-607, HG-615, and this paragraph. The individual modules shall be limited to a maximum input of 400,000 Btuh (gas), 3 gal/hr (11 L/hr) (oil), or 115 kW (electricity). (3) Each module of a modular hot water heating boiler shall be equipped with: (a) safety relief valve, see HG-701 (b) drain valve, see HG-715(c) (b) Assembled Modular Boilers (1) The individual modules shall be manifolded together at the job-site without any intervening valves. The header or manifold piping is field piping and is exempt from Article 2, Part HG, HF, HE, or HC. (3) The assembled modular hot water heating boiler shall also be equipped with: (a) makeup water connection, see HG-705(b) (b) provision for thermal expansion, see HG-709 (c) stop valves, see HG-710.2

Modular Boiler cont…

Modular Boilers cont……
(a) Each module of a modular hot water heating boiler shall be equipped with: (1) pressure / altitude gage, see 0-611; (2) thermometer, see HG-612; (3) temperature control that will cut off the fuel supply when the temperature reaches an operating limit, which shall be less than the maximum allowable temperature. (b) The assembled modular hot water beating boiler shall also be equipped with: (1) a safety limit control that will cut off the fuel supply to prevent the water temperature from exceeding the maximum allowable temperature at the boiler outlet. The control shall be constructed to prevent a temperature setting above the maximum. This control shall be located within 3 ft. of the fitting connecting the last module to the heating supply piping. (2) low water fuel cutoff, see HG-614.

Bonus Question # 2
Finish this phrase;
Give a man a fish and feed him for the day, teach him to fish and…..

he will spend all day in the boat drinking beer.

Make-up Feedwater
(b) Hot Water Boilers. Makeup water may be introduced into a boiler through the piping system or through an independent connection. The water flow from the independent connection shall not discharge directly against parts of the boiler exposed to direct radiant heat from the fire. Makeup water shall not be introduced through openings or connections provided exclusively for inspection or cleaning, safety relief valve, pressure gage, or temperature gage. The makeup water pipe shall be provided with a check valve near the boiler and a stop valve or cock between the check valve and the boiler or between the check valve and the piping system.
NOTE: (b) The minimum pressure rating of all valves or cocks shall be at least equal to the pressure stamped upon the boiler, and the temperature rating of such valves or cocks, including all internal components, shall be not less than 250°F.

Drains
(c) Drain Valve. Each steam or hot water boiler shall have one or more drain connections. fitted with valves or cocks connecting to the lowest water containing spaces. The minimum size of the drain piping, valves, and cocks shall be ¾ in. The discharge piping shall be full size to the point of discharge. When the blowoff connection is located at the lowest water containing space, a separate drain connection is not required.

(d) Minimum Pressure Rating. The minimum pressure rating of valves and cocks used for blowoff or drain purposes shall be at least equal to the pressure stamped on the boiler but in no case less than 30 psi. The temperature rating of such valves and cocks shall not be less than 250°F.

Stop Valves
(a) Stop valves shall be located at an accessible point in the supply and return pipe connections as near the boiler nozzle as is convenient and practicable. of a single hot water heating boiler installation to permit draining the boiler without emptying the system. (b) When the boiler is located above the system and can be drained without draining the system, stop valves may be eliminated.

Stop Valves cont…….
(a) All valves or cocks shall conform with the applicable portions of HF203 and may be ferrous or nonferrous. (b) The minimum pressure rating of all valves or cocks shall be at least equal to the pressure stamped upon the boiler, and the temperature rating of such valves or cocks, including all internal components, shall be not less than 250°F. (c) Valves or cocks shall be flanged, threaded or have ends suitable for welding or brazing. (d) All valves or cocks with stems or spindles shall have adjustable pressure type packing glands and, in addition, all plug type cocks shall be equipped with a guard or gland. The plug or other operating mechanism shall be distinctly marked in line with the passage to indicate whether it is opened or closed. (e) All valves or cocks shall have tight closure when under boiler hydrostatic test pressure

Typical Atmospheric Gas Fuel Train, over 400,000 but less than 2,500,001 BTU/Hr

ANSI Z21.13
GENERAL NOTE: Since boiler design may vary, American National Standard for Gas-Fired LowPressure Steam and Hot-Water Boilers, ANSI Z21.13, does not contain a typical fuel train; however, through laboratory testing procedures, ANSI Z21.13 does determine that safe lighting of the boiler will be accomplished; this Standard illustrates a typical fuel train for boilers. The specific fuel train diagram for boilers complying with ANSI Z21.13 is supplied in the boiler manufacturer's instructions.

Controls, accepted and listed
All controls and safety devices covered by CSD-1 must be accepted and listed for the intended service by a nationally recognized testing agency such as, but not limited to, AGA, FM, or UL.

Drip Leg
CF-140 Drip Legs When a vertical section of piping supplied by the manufacturer is on the upstream side of the gas controls, a trap (drip leg) shall be included. When a vertical section of piping is not supplied, installation instructions shall require the installation of a trap at the inlet of the gas connection to the boiler.

Gas shutoff valves
(a) Manually operated main shutoff and pilot shutoff valves, in sizes
larger than NPS 2 or for pressures greater than 1/2 psig (3.4 kPa gage), shall be ball or lubricated plug type, with stops. All manually operated valves shall be the lever-handled type and shall have the handle permanently attached, parallel to the gas flow when in the open position. The handle shall be accessible and shall clearly indicate the "on" and "off'" positions. (b) An accessible, manually operated valve shall be provided upstream from all other main gas line controls. The pilot gas supply shall be obtained upstream from this valve.

(c) A manually operated pilot shutoff valve shall be located in the gas supply line to the pilot burner(s).

Gas shutoff valves and leak test valves
(d) A manually operated shutoff valve, as described in (a) above, shall be provided after the downstream safety shutoff valve for each main burner. A manually operated leak test valve (NPS 1/8 or larger) shall be installed between the upstream valve and this manually operated valve. When two safety shutoff valves are provided in the fuel train an additional leak test valve shall be installed after the upstream valve, or other provision shall be made so that each safety shutoff valve may be tested independently of the others. The outlet of the leak test valve(s) shall be plugged or capped, except when used for testing

Typical gas fuel train

Atmospheric Vents and Gas Vent. Bleed. or Relief Lines
(a) Gas pressure regulators including second stage LP-gas pressure regulators, not incorporating integral vent limiters, pressure interlock switches, and all other valve train components requiring atmospheric air pressure to balance a diaphragm or other similar device, shall be provided with a pipe-threaded connection for the vent line. This line shall be piped by the installer to the outdoors at a safe point of discharge as determined by the authority having jurisdiction. A means shall be provided at the terminating point to prevent a stoppage of the line by foreign material, moisture, or insects.

More Atmospheric Vents and Gas Vent. Bleed. or Relief Lines
(b) Atmospheric vent lines, when manifolded, shall be connected into a common vent line having a cross-sectional area not less than the area of the largest vent line plus 50% of the areas of the additional vent lines.

Some things we did not cover
Specific burner assemblies Filters or Strainers Gas Pressure Regulators Electrically heated boilers Automatic Ignition Devices Gas, Oil and Electric Modular Boilers

Over Pressure Protection Relief Valves
Pressure Switches Oil Fired Boilers

and much, much more…

Combustion Air, Typical
One opening within upper 12” and one opening within lower 12” of boiler room. Minimum ¼” mesh screen. Each opening must have 1 square inch per 4,000 BTU/Hr for a total of all fuel burning equipment in the boiler room.

When in doubt, refer to International Mechanical Code or local building officials.

Expansion Tanks
Closed Heating Systems. An expansion tank shall be installed that will be consistent with the volume and capacity of the system. If the system is designed for a working pressure of 30 psi (207 kPa) or less, the tank shall be suitably designed for a minimum hydrostatic test pressure of 75 psi (517 kPa). Expansion tanks for Systems designed to operate above 30 psi (207 kPa) shall be constructed in accordance with Section VIII, Division 1. Alternatively, a tank built to Section X requirements may be used if the pressure and temperature ratings of the tank are equal to or greater than the pressure and temperature ratings of the system. Provisions shall be made for draining the tank without emptying the system, except for pre-pressurized tanks. The minimum capacity of the closed type expansion tank may be determined from Tables HG-709.1 and HG-709.2 or from the following formula where the necessary information is available:

Turn off the power!
(a) A disconnecting means capable of being locked in the open position shall be installed at an accessible location at the boiler so that the boiler can be disconnected from all sources of potential. This disconnecting means shall be an integral part of the boiler or adjacent to it.

Emergency Shut Down
A manually operated remote shutdown switch or circuit breaker shall be located just outside the boiler room door and marked for easy identification. Consideration should be given to the type and location of the switch to safeguard against tampering. If the boiler room door is on the building exterior, the switch should be located just inside the door. If there is more than one door to the boiler room, there should be a switch located at each door.

Water Heaters (Stamped HLW)
The rules of Part HLW are restricted to potable water heaters and water storage tanks for operation at pressures not exceeding 160 psi and water temperatures not in excess of 210°F. Based on the Committee's consideration, water heaters are exempted when none of the following limitations is exceeded: (a) heat input of 200,000 Btu/hr; (b) water temperature of 210°F; (c) nominal water-containing capacity of 120 gal. except that they shall be equipped with safety devices in accordance with the requirements of HLW-800.

Hot water storage tanks
ASME Section VIII, Division 1, (pressure vessels) U-1 (g) require hot water supply storage tanks heated by steam or any other indirect means, be ASME Code constructed if any of the following is exceeded: 1 (1) a heat input of 200,000 Btu/Hr (58.6 kW); 2 (2) a water temperature of 210○F (99○C);
3 (3) a nominal water containing capacity of 120 gal;

Interpretation
The ASME Committee for Section VIII issued this interpretation on 9/24/86, (File: BC86-301) Question: U-1(c)(7) exempts hot water supply tanks from the requirements of Section VIII, Division 1, provided the limitation in that paragraph is not exceeded. For the purpose of satisfying U-1(c)(7)(a), must the heat exchange take place inside the vessel?
(note: U-1(c)(7) is now U-1 (g) in 2001 edition and U1(c)(7)(a) is now U-1 (g)(1) in 2001 edition.) Reply: No.

Water Heater Safety Relief Valves
(a) Each water heater shall have at least one officially rated safety relief valve or at least one officially rated pressure temperature relief valve. The valve(s) shall be marked with the ASME Code Symbol V or HV to evidence compliance with the construction and rating requirements of the ASME Boiler and Pressure Vessel Code. No safety relief valve shall be smaller than 3/4 in. standard pipe size.

Water Heater Safety Relief Valves continued
(b) The pressure setting shall be less than or equal to the maximum allowable working pressure of the water heater. However, if any of the other components in the hot water supply system (such as valves, pumps. expansion or storage tanks. or piping) have a lesser working pressure rating than the water heater. the pressure setting for the relief valve(s) shall be based upon the component with the lowest maximum allowable working pressure rating. If more than one safety relief valve is used, the additional valve(s) may be set within a range not to exceed 10% over the set pressure of the first valve.

And more Water Heater Safety Relief Valves continued
(c) The required relieving capacity in Btu/hr of the safety relief valve shall not be less than the maximum allowable input unless the water heater is marked with the rated burner input capacity of the water heater on the casing in a readily visible location, in which case the rated burner input capacity may be used as a basis for sizing the safety relief valves. The relieving capacity for electric water heaters shall be 3500 Btu/hr per kW of input. In every case, the following requirements shall be met. Safety relief valve capacity for each water heater shall be such that with the fuel burning equipment installed and operated at maximum capacity the pressure cannot rise more than 10% of maximum allowable working pressures.

Water Heater Name Plate

Stamping of Water Heater Name Plate
If the required marking or stamping is to be covered by insulation, jacket. or other form of casing, one of the following shall be provided:
(a) an opening with a removal cover for viewing the marking or stamping; (b) a nameplate, located in a conspicuous place on the jacket, duplicating the required Code Symbol and data. This plate shall be at least 3 in. x 4 in. (76 mm x 102 mm) in size marked with letters and numerals at least 1/8 in. (3.2 mm) high and of either metallic material attached by mechanical means or of any material attached by an adhesive system meeting the requirements of Appendix 3.

Power Boilers
Power Boiler means any boiler exceeding the miniature boiler size which generates steam or vapor at a pressure more than fifteen pounds per square inch gauge (PSIG.)

High Temperature Boiler is a boiler in which water or other fluid is heated and intended for operation at pressures in excess of 160 psig and\or temperatures in excess of 250 degrees Fahrenheit.

Common over sights of Power Boiler installations
The number of safety valves required when over 500 sq. feet H.S. Safety valve capacity requirements and how to calculate them.

and my favorite….

Power Piping!

Power Boilers and some CSD-1
(a) Each automatically fired high-pressure steam boiler, except miniature boilers, shall have at least two automatic low-water fuel cutoff devices. Each cutoff device shall be installed to prevent startup and to cut off the boiler fuel or energy supply automatically when the surface of the water falls to a level not lower than the lowest visible part of the gage glass. One control shall be set to function ahead of the other. Each miniature boiler shall have at least one low-water fuel cutoff device (see also CW-210).

NOTE: CSD-1 is not applicable for boilers exceeding a BTU input of 12,500,000

Some more CSD-1 and Power Boilers
Two Pressure controls are required: One operator and one safety limit with lockout requiring manual reset.
(f) The steam pressure supply connections to a pressure switch shall not be less than NPS 1/4 when the pipe is of nonferrous material. Ferrous connections shall be not less than NPS 1/2 for lengths up to 5 ft (1.5 m), and not less than NPS 1 for lengths over 5 ft (1.5 m). Tubing suitable for the temperatures and pressures involved, having an inside diameter at least equal to that of standard pipe, may be substituted for pipe. (g) Pressure controls should have separate pressure source connections; however, manifolding is permitted. When multiple controls are fed from a manifold, the manifold and common source connection to the boiler shall be one pipe size larger than that required in (f) above. Individual controls are to be piped from the manifold according to the provisions of (f) above.

Power Boiler Pressure Gage
PG-60.6.1 Each boiler shall have a pressure gage so located that it is easily readable. The pressure gage shall be installed so that it shall at all times indicate the pressure in the boiler. Each steam boiler shall have the pressure gage connected to the steam space or to the water column or its steam connection. A valve or cock shall be placed in the gage connection adjacent to the gage.

The dial of the pressure gage shall be graduated to approximately double the pressure at which the safety valve is set, but in no case to less than 1 ½ times this pressure.

Power Boiler Gage Glass
PG-60.1 Water Level Indicators. All boilers having a fixed water level (steam and water interface) shall have at least one gage glass (a transparent device that permits visual determination of the water level). Boilers not having a fixed water level, such as forced-flow steam generators and high-temperature water boilers of the forced circulation type, are not required to have a gage glass.

PG-60.1.6 Each gage glass shall be fitted with a drain cock or valve having an unrestricted drain opening of not less than ¼ in. (6 mm) diameter to facilitate cleaning. When the boiler MAWP exceeds 100 psi (690 k?a), the gage glass shall be furnished with a connection to install a valved drain to a point of safe discharge.

Blowoff vs. Blowdown Piping
Blowoff systems are operated intermittently to remove accumulated sediment from equipment and/or piping, or to lower boiler water level in a rapid manner. Blowdown Systems are primarily operated continuously to control the concentrations of dissolved solids in the boiler water. Two shutoff valves are required in the blowoff system. Installer shall have a “S” or “PP” stamp for new construction. Only one shutoff valve is required in the blowdown system.

Blowoff vs. Blowdown Piping
All power boilers are required to have blowoff piping.
Boilers exceeding 100 psi shall have two valves. Two slow or one fast and one slow acting valve is required. Except on traction and portable steam boilers, electric not exceeding 100 gal. along with all miniature boilers.

Power Boilers are not required to have blowdown piping. All of the external piping within the scope of Section shall be listed on a Manufacture’s Data Report.

Manufacture’s Data Reports
Manufacturers' Data Reports and all associated Partial Data Reports shall be furnished to the purchaser, the inspection agency, and the state, municipal, or provincial authority at the place of installation. Partial Data Reports for pressure parts requiring inspection under this Section, and which are furnished by other than the Manufacturer having Code responsibility for the boiler or the superheater, waterwall, or economizer, shall be executed by the parts manufacturer and the Inspector in accordance with the requirements of this Section.

This training is concluded.

Thank you


								
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