Haw. Code R. § 12-223.1-13 - Operating systems

(a) Feedwater.

(1) Steam heating boilers. Feedwater or water treatment shall be introduced into a boiler through the return piping system. Alternatively, feedwater or water treatment shall be introduced through an independent connection. A cross or equivalent fitting shall be placed in the water piping connection at every right angle turn to facilitate cleaning and inspection. The water flow from the independent connection shall not discharge directly against parts of the boiler exposed to direct radiant heat from the fire. Feedwater or water treatment shall not be introduced through openings or connections provided for inspection or cleaning, safety valve, water column, water-gage glass, or pressure gage. The feedwater pipe shall be provided with a check valve, or a backflow preventer containing 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 return pipe system;

(2) Hot-water heating 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, or a backflow preventer containing 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; and

(3) The following shall apply to potable water heaters:

(A) Water supply shall be introduced into a water heater through an independent water supply connection. Feedwater shall not be introduced through openings or connections provided for cleaning, safety relief valves, drain, pressure gage, or temperature gage; and

(B) If the water supply pressure to a water heater exceeds seventy-five per cent (75%) of the set pressure of the safety relief valve, a pressure reducing valve is required.

(b) Stop valves. Stop valves shall conform with the applicable portions of an acceptable code of construction and may be ferrous or nonferrous. The minimum pressure rating of all stop valves shall be at least equal to the pressure stamped upon the boiler, and the temperature rating of such stop valves shall be not less than 250 degrees Fahrenheit.

(1) The following shall apply to steam heating, hot-water heating, and hot-water supply boilers:

(A) When a stop valve is used in the supply pipe connection of a single steam boiler, there shall be one installed in the return pipe connection;

(B) Stop valves for single hot-water heating and hot-water supply heating boilers shall be located at an accessible point in the supply and return pipe connections as near to the boiler as possible, to permit draining the boiler without emptying the system; and

(C) Stop valves shall be used in each supply and-return pipe connection for boiler installations of two or more heating boilers connected to a common system; and

(2) Potable water heaters. Stop valves shall be installed in the supply and discharge pipe connections of a water heater installation to permit draining the water heater without emptying the system.

(c) Fuel. Fuel systems shall be installed in accordance with jurisdictional and environmental requirements, manufacturer's recommendations, and industry standards, as applicable.

(d) Electrical. The following shall apply to steam heating, hot-water heating, and hot-water supply boilers:

(1) All wiring for controls, heat generating apparatus, and other appurtenances necessary for the operation of the heating boilers shall be installed in accordance with the provisions of national or international standards and shall comply with the applicable local electrical codes;

(2) 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;

(3) A manually operated remote shutdown switch or circuit breaker shall be located just outside the equipment room door and marked for easy identification. Consideration should also be given to the type and location of the switch to safeguard against tampering;

(4) If the equipment room door is on the building exterior, the shutdown switch should be located just inside the door. If there is more than one door to the equipment room, there shall be a shutdown switch located at each door of egress;

(5) For atmospheric-gas burners, and oil burners where a fan is on a common shaft with the oil pump, the complete burner and controls should be shut off; and

(6) For power burners with detached auxiliaries, only the fuel input supply to the firebox need be shut off.

(e) Potable water heaters. The following shall apply to potable water heaters:

(1) All wiring for controls, heat generating apparatus, and other appurtenances necessary for the operation of the potable water heaters shall be installed in accordance with the provisions of national or international standards and comply with the applicable local electrical codes;

(2) A disconnecting means capable of being locked in the open position should be installed at an accessible location at the heater so that the heater can be disconnected from all sources of potential. This disconnecting means shall be an integral part of the heater or adjacent to it;

(3) For atmospheric-gas burners, and oil burners where a fan is on a common shaft with the oil pump, the complete burner and controls should be shut off;

(4) For power burners with detached auxiliaries, only the fuel input supply needs be shut off;

(5) A manually operated remote shutdown switch or circuit breaker shall be located just outside the equipment room door and marked for easy identification. Consideration should also be given to the type and location of the switch to safeguard against tampering; and

(6) If the equipment 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 equipment room, there should be a switch located at each door of egress.

(f) Controls and heat generating apparatus. The following shall apply to controls and heat generating apparatus:

(1) Oil and gas-fired and electrically heated heating boilers and water heaters shall be equipped with suitable primary (flame safeguard) safety controls, safety limit controls, and burners or electric elements as required by a nationally or internationally recognized standard;

(2) The symbol of the certifying organization that has investigated such equipment as having complied with a nationally recognized standard shall be affixed to the equipment and shall be considered as evidence that the unit was manufactured in accordance with that standard; and

(3) These devices shall be installed in accordance with jurisdictional and environmental requirements, manufacturer's recommendations, and industry standards, as applicable.

(g) Ventilation and combustion air. The following shall apply to ventilation and combustion air:

(1) The equipment room shall have an adequate air to permit clean, safe combustion, minimize soot formation, and maintain a minimum of nineteen and a half per cent (19.5%) oxygen in the air of the equipment room and sufficient to maintain ambient temperatures as recommended by the boiler, heater, or vessel manufacturer;

(2) When combustion air is supplied to the boiler, heater, or vessel by an independent duct, with or without the employment of power ventilators or fans, the duct shall be sized and installed in accordance with the manufacturer's recommendations. However, ventilation for the equipment room must still be considered;

(3) Unobstructed air openings shall be sized based on the manufacturer's recommendations, or as specified by the National Fire Protection Association (NFPA) standards for oil and gas burning installations for the particular job conditions, or one (1) square inch of free area per 2000 Btu per hour (586 W) maximum fuel input of the combined burners located in the equipment room. The equipment room supply openings shall be kept clear at all times;

(4) Power ventilators or fans shall be sized based on 0.2 cfm for each 1000 Btu per hour (293 W) of maximum fuel input for the combined burners of all heating boilers and heaters located in the equipment room. Additional capacity may be required for other fuel burning equipment in the equipment room;

(5) When power ventilators or fans are used to supply combustion air, they shall be installed with interlock devices so that burners will not operate without an adequate number of ventilators/fans in operation;

(6) When power ventilators or fans are used to supply combustion air, they shall be installed with interlock devices so that burners will not operate without an adequate number of ventilators/fans in operation;

(7) The size of openings specified in paragraph (3) may be reduced when special engineered air supply systems approved by the department are used; and

(8) Care should be taken to ensure that steam, water and fluid lines are not routed across combustion air openings, where freezing may occur.

(h) Breeching and dampers. Breeching and dampers shall be installed in accordance with jurisdictional and environmental requirements, manufacturer's recommendations, and industry standards, as applicable.

(i) Burners and stokers. Burners and stokers shall be installed in accordance with jurisdictional and environmental requirements, manufacturer's recommendations, and industry standards, as applicable.

(j) Lighting. The equipment room shall be well-lit and have an emergency light source for use in the case of a power failure.

(k) Emergency valves and controls. All emergency shut-off valves and controls shall be accessible from a floor, platform, walkway, or runway. Accessibility shall mean within a six (6) feet elevation of the standing space and not more than twelve (12) inches horizontally from the standing space edge.

(l) Chimney or stack. Chimneys or stacks shall be installed in accordance with the department's requirements, manufacturer's recommendations, and industry standards, as applicable.

(m) Ash removal. Ash removal systems shall be installed in accordance with jurisdictional and environmental requirements, manufacturer's recommendations, and industry standards, as applicable.

(n) Return pipe connections. The following shall apply to return pipe connections:

(1) The return pipe connections of each boiler supplying a gravity return steam heating system shall be so arranged as to form a loop so that the water in each boiler cannot be forced out below the safe water level; and

(2) Provision shall be made for cleaning the interior of the return piping at or close to the boiler. Washout openings should be used for return pipe connections and the washout plug placed in a tee or a cross so that the plug is directly opposite and as close as possible to the opening in the boiler.

(o) Bottom blowoff and drain valves. The following shall apply to bottom blowoff and drain valves of steam heating, hot-water heating, and hot-water supply heating boilers:

(1) Each steam boiler shall have a bottom blowoff connection fitted with a valve or cock connected to the lowest water space practicable with a minimum size as shown in the NBIC. The discharge piping shall be full size to the point of discharge. Heating boilers having a capacity of twenty-five (25) gallons or less are exempt from the above requirements, except that they shall have a NPS three-fourths (3/4) minimum drain valve;

(2) 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. All parts of the boiler must be capable of being drained (the boiler design will dictate the number and size of drains). The minimum size of the drain piping, valves, and cocks shall be NPS 3/4. 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; and

(3) 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 thirty (30) psig. The temperature rating of such valves and cocks shall not be less than 250 degrees Fahrenheit.

(p) Each potable water heater shall have a bottom drain pipe connection fitted with a valve or cock connected with the lowest water space practicable. The minimum size bottom valve shall be NPS three-fourths (3/4). Any discharge piping connected to the bottom drain connection shall be full size to the point of discharge.

(q) Provisions for thermal expansion of expansion tanks and piping for steam heating, hot-water heating, and hot-water supply heating boilers shall comply with the following:

(1) Expansion tanks for hot-water heating and hot-water supply heating boilers shall be installed so that all hot-water heating systems incorporating hot-water tanks or fluid relief columns prevent freezing under normal operating conditions;

(2) Heating systems with an open expansion tank shall have an indoor overflow from the upper portion of the expansion tank in addition to an open vent, the indoor overflow shall be carried within the building to a suitable plumbing fixture or drain;

(3) In closed heating systems an expansion tank shall be installed in a closed heating system that will be consistent with the volume and capacity of the system. If the system is designed for a working pressure of thirty (30) psig or less, the tank shall be suitably designed for a minimum hydrostatic test pressure of seventy-five (75) psig. Expansion tanks for systems designed to operate above thirty (30) psig shall be constructed in accordance with an acceptable code of construction. Provisions shall be made for draining the tank without emptying the system except for pressurized tanks. The minimum capacity of the closed-type expansion tank should be determined from NBIC Part 1, Tables 3.7.9.1-a and 3.7.9.1-b or from the following formula where the necessary information is available:

US Customary:

Vt = (0.00041T - 0.0466)Vs

(Pa/Pf) - (Pa/Po)

where,

Vt = minimum volume of tanks, gallons

Vs = volume of system, not including tanks, gallons

T = average operating temperature, °F

t1 = lower temperature

t2 = higher temperature

Pa = atmospheric pressure, psia

Pf = fill pressure, psia

Po = maximum operating pressure, psia Metric:

Vt = (0.000738T - 0.3348)Vs

(Pa/Pf) - (Pa/Po)

where,

Vt = minimum volume of tanks, liters

Vs = volume of system, not including tanks, liters

T = average operating temperature, °C

Pa = atmospheric pressure, kPa

Pf = fill pressure, kPa

Po = maximum operating pressure, kPa; and

(4) Hot-water supply systems. If a system is equipped with a check valve or pressure-reducing valve in the cold-water inlet line, consideration should be given to the installation of an airtight expansion tank or other suitable air cushion. Otherwise, due to the thermal expansion of the water, the safety relief valve may lift periodically. If an expansion tank is provided, it shall be constructed in accordance with an acceptable code of construction. Except for pre-pressurized tanks, which should be installed on the cold-water side, provisions shall be made for draining the tank without emptying the system (for a typical acceptable installation see Exhibit 7, titled, "Hot Water Boilers in Battery Acceptable Piping Installation", dated October 1, 2023, which is made a part of this chapter and located at the end of this chapter).

(r) Piping for steam heating, hot-water heating, and hot-water supply boilers. Provisions shall be made for the expansion and contraction of steam and hot water mains connected to boiler (s) so there will be no undue strain transmitted to the boiler(s) (for typical schematic arrangements of piping incorporating strain absorbing joints for steam and hot-water heating boilers see Exhibit 5, titled, "Steam Boilers in Battery -Pumped Return Acceptable Piping Installation", dated October 1, 2023, which is made a part of this chapter and located at the end of this chapter. Exhibit 6, titled, "Steam Boilers in Battery - Gravity Return Acceptable Piping Installation", dated October 1, 2023, which is made a part of this chapter and located at the end of this chapter, and Exhibit 7, titled, "Hot Water Boilers in Battery Acceptable Piping Installation", dated October 1, 2023, which is made a part of this chapter and located at the end of this chapter).

(s) Expansion tanks and piping for potable water heaters. The following shall apply to expansion tanks and piping for potable water heaters:

(1) If a system is equipped with a check valve or pressure-reducing valve in the cold-water inlet line, consideration should be given to the installation of an airtight expansion tank or other suitable air cushion. Otherwise, due to the thermal expansion of the water, the safety relief valve may lift periodically. If an expansion tank is provided, it shall be constructed in accordance with an acceptable code of construction. Except for pre-pressurized diaphragm-type tanks, which should be installed on the cold-water side, provisions shall be made for draining the tank without emptying the system; and

(2) Piping. Provisions shall be made for the expansion and contraction of hot water mains connected to potable water heater(s) so that there will be no undue stress transmitted to the potable water heater (s).

TABLE 3.7.9.1-a

EXPANSION TANK CAPACITIES FOR GRAVITY HOT-WATER SYSTEMS

Based on a two-pipe system with average operating water temperature 170°F(77°C), using cast-iron column radiation with heat emission rate 150 Btu/hr/ft2 (473 W/m2) equivalent direct radiation)
Installed Equivalent Direct Radiation, ft2 (m2) (Note)	No.	Tank Capacity, gallon (l)
up to 350 (33)	1	18 (68)
up to 450 (42)	1	21 (79)
up to 650 (60)	1	24 (91)
up to 900 (84)	1	30 (114)
up to 1,100 (102)	1	35 (132)
up to 1,400 (130)	1	40 (151)
up to 1,600 (149)	2	60 (227)
up to 1,800 (167)	2	60 (227)
up to 2,000 (186)	2	70 (265)
up to 2,400 (223)	2	80 (303)

Note:

For systems with more than 2,400 ft² (223 m²) of installed equivalent direct water radiation, the required capacity of the cushion tank shall be increase on the basis of 1 gallon (3.79 l) tank capacity/33 ft² (3.1 m²) of additional equivalent direct radiation.

TABLE 3.7.9.1-b

EXPANSION TANK CAPACITIES FOR FORCED HOT-WATER SYSTEMS

Based on average operating water temperature 195°F [91°C], fill pressure 12 psig [83 kPa], and maximum operating pressure 30 psig [200 kPa]
Tank Capacities, gallon (l)
System Volume	Pressurized Diaphragm Type	Nonpressurized Type
100 (379)	9 (34)	15 (57)
200 (757)	17 (64)	30 (114)
300 (1136)	25 (95)	45 (170)
400 (1514)	33 (125)	60 (227)
500 (1893)	42 (159)	75 (284)
1,000 (3785)	83 (314)	150 (568)
2,000 (7571)	165 (625)	300 (1136)

Note: System volume includes volume of water in boiler, radiation, and piping, not including the expansion tank. Expansion tank capacities are based on an acceptance factor of 0.4027 for pre-pressurized types and 0.222 for non-pressurized types. For other cases or metric calculations see Chapter 12 of the 1996 HVAC Systems and Equipment Volume of the ASHRAE Handbook.

(t) Carbon monoxide (CO) detector/alarm. The owner or user shall install a carbon monoxide detector/alarm in equipment rooms where fuel fired boilers are located in accordance with manufacturer's recommendation, and industry standards, as applicable.

(u) Testing and final acceptance. The completed boiler shall be pressure tested in the shop or in the field in accordance with the original code of construction and documented on the appropriate manufacturer's data report.

(1) The installer shall exercise care during installation to prevent loose weld material, welding rods, small tools, and miscellaneous scrap metal from getting into the vessel. Prior to making the final closure, the installer shall inspect the interior of the vessel and its appurtenances for the presence of foreign debris, and if present it shall be removed;

(2) Subject to the department's requirements, a leak test may be performed on any components whose pressure test is not documented under the items' manufacturer's data report. This leak test should not exceed ninety (90%) of the lowest pressure relief device setpoint. The test data shall be recorded, and the data made available as required;

(3) Prior to final acceptance, an operational test shall be performed on the completed installation. The test shall include operating controls, limit controls and safety devices, and witnessed as required by the department. The test data shall be recorded, and the data made available to the department as evidence that the installation complies with provisions of the governing code(s) of construction; and

(4) All fuel fired boiler and fuel fired pressure vessel combustion air-fuel ratios shall be analyzed, adjusted, and values documented during commissioning to meet emission requirements and limits of the manufacturer.

Notes

Haw. Code R. § 12-223.1-13

[Eff and comp 12/21/2019] (Auth: HRS § 397-4) (Imp: HRS § 397-4) Am and comp 9/8/2024