Illinois Administrative Code › Title 77 - PUBLIC HEALTH › Part 890 - ILLINOIS PLUMBING CODE › Subpart I - WATER SUPPLY AND DISTRIBUTION › Section 890.1220 - Hot Water Supply and Distribution

Current through Register Vol. 48, No. 28, July 12, 2024
a) All water heaters shall comply with
				Appendix A.Table A (Approved Standards for Plumbing
				Appliances/Appurtenances/Devices) and ASHRAE 90 Standards. Hot water storage
				tanks shall meet construction requirements of ASME, AGA or UL listed in
				Appendix A.Table A (Approved Standards for Plumbing
				Appliances/Appurtenances/Devices), as appropriate. Hot water supply boilers
				with heat input in excess of 200,000 BTU per hour, water temperature in excess
				of 200 degrees Fahrenheit, or capacity in excess of 120 gallons shall also
				comply with the requirements of 41 Ill. Adm. Code 120(Boiler and Pressure
				Vessel Safety). Smaller water storage tanks that are not subject to ASME
				requirements shall be constructed of durable materials and constructed to
				withstand 150 psi. (See Appendix I.Illustrations L and M, for examples of
				typical water heater installations.)
1) All
				equipment used for heating and storage of hot water shall bear the marking of
				an approved testing agency certifying that it has been tested and approved and
				listed as meeting the requirements of the applicable standard. Listing by UL,
				the Canadian Standards Association (CSA), or National Board of Boiler and
				Pressure Vessel Inspectors, or the ASME Standard shall constitute evidence of
				conformance with these standards.
2) Solar Hot Water Heat Exchangers
A) A hot water heat exchanger used in a
				solar-heated system may be of single wall construction if a non-toxic transfer
				fluid with no conditioning chemicals in the system is used.
B) A hot water exchanger used in a
				solar-heated system using a toxic transfer fluid or having conditioning
				chemicals in the system shall be separated from the potable water by double
				wall construction that has an air gap vented to the atmosphere between the
				walls.
3) A hot water
				heat exchanger may be of single wall construction if a non-toxic transfer fluid
				with no conditioning chemicals in the system is used.
4) A hot water heat exchanger operating at or
				below 65 psi using a toxic transfer fluid or having conditioning chemicals in
				the system shall be separated from the potable water by double wall
				construction, with an air gap open to the atmosphere between the two
				walls.
5) A hot water heat
				exchanger shall not be permitted on any hot water boiler system operating in
				excess of 65 psi or 250 degrees Fahrenheit, unless:
A) the heat exchanger is
				double-walled;
B) the heat
				exchanger has an air gap open to the atmosphere between the two walls;
				and
C) the heat exchanger has a
				pressure gradient monitor system with a "fail-safe to off" switch installed to
				isolate the heat exchanger from the potable cold or hot water system. If
				pressure on the potable water side reaches a pressure less than 20 psi above
				the pressure of the transfer fluid or steam and a pressure-reducing valve is
				installed on the inlet to the heat exchanger with a setting 20 psi lower than
				the potable water pressure at the heat exchanger, an audible alarm shall be
				activated and the heat exchanger shall be automatically shut off until the
				alarm and heat exchanger can be reset manually.
6) Any boiler using toxic chemicals shall
				have a label with a minimum size of 5 inches by 5 inches attached to the boiler
				in a conspicuous place. The label shall read as follows:
WARNING
Chemicals and additives used to treat the boiler feed water
				  in this boiler are not approved for potable water. The steam or hot water
				  produced by this boiler is not potable. If the steam or hot water produced by
				  this boiler is used to heat water, the water will not be considered potable if
				  the steam and potable water are mixed.
7) Indirect, External, Submerged Coils.
				Indirect, external, tankless or submerged coils used in heating water shall be
				equipped with a thermostatic mixing valve or valves when not connected to a
				storage tank. A pressure relief valve shall be installed on the cold water
				inlet of the tank. A properly sized temperature and pressure relief valve,
				based upon the energy input rating of the coils, shall be installed on the
				tempered line with the temperature sensing element immersed in the tempered
				water line as close as possible to the mixing valve.
8) Water Heaters Used for Space Heating. Any
				water heater to be used for space heating, in addition to hot water supply,
				shall conform to ANSI Z21.10.1,
				Z21.10.1a and Z21.10.1b and shall be constructed for continuous use, and the
				piping for space heating shall be conducted to a proper terminal heating
				device.
A) A thermostatic mixing valve,
				conforming to ASSE 1017, shall be installed on the hot water line to the
				plumbing fixtures. (The mixing valve shall be set to prevent temperatures
				exceeding 120 degrees Fahrenheit from reaching the plumbing
				fixtures.)
B) A single check valve
				shall be installed in the cold water line supplying the water heater. This will
				prevent hot water backing up from the heating unit to the plumbing
				fixtures.
C) A properly sized and
				approved expansion tank shall be located on the outlet side of the check valve
				in the water heater's cold water supply, with no shut-off valve between the
				heater and expansion tank.
D)
				Valves (manual, automatic) supplying hot water to the heat transfer unit for
				space heating shall have a minimum of a 1/8-inch orifice. This will prohibit
				potable water from standing in the heat transfer unit when not in use. This
				does not prohibit full shut off/isolation valves on either side of the pump
				within a heat transfer unit, as needed, to permit the servicing of the
				pump.
E) The water heater
				instructions shall have a statement specifying that piping and components
				connected to the water heater for the space heating application shall be
				suitable for use with potable water, and the water heater shall not exceed a
				developed length of more than 25 feet from the heating coil.
F) A statement specifying that toxic
				chemicals, such as those used for boiler treatment, shall not be introduced
				into the potable water used for space heating shall be included in the
				instructions. A label with the following words shall be firmly attached to any
				water heater used for space heating: "DO NOT INJECT TOXIC MATERIALS INTO THIS
				TANK."
G) A statement specifying
				that a water heater that will be used to supply potable water shall not be
				connected to any heating system or components previously used with a
				non-potable water heating appliance shall be included in the installation
				instructions.
H) Each water heater
				shall bear a statement on the rating plate as follows: "SUITABLE FOR POTABLE
				WATER HEATING AND SPACE HEATING."
9) Point-of-Use Water Heaters. Point-of-use
				water heaters shall meet the following requirements:
A) Non-storage and non-pressurized units
				intended to deliver water temperatures exceeding 110 degrees Fahrenheit, or
				with no mechanical or electrical temperature limiting device, shall have the
				faucet located at least 3 inches from the 110 degrees Fahrenheit hot water or
				cold water faucet. Faucet outlets shall have labels clearly and conspicuously
				indicating extremely hot water. These units are exempt from the requirement
				that a relief valve or valves be used to protect against excessive or unsafe
				temperature or pressure.
B) Units
				intended to deliver water temperatures 110 degrees Fahrenheit or less shall
				have an internal burnout element. These units are exempt from the requirement
				that a relief valve or valves to be used to protect against excessive or unsafe
				temperature and/or pressure.
C) All
				pressurized point-of-use water heaters, other than those in subsection
				(a)(9)(A) or (B), shall be provided with proper temperature and pressure
				relief.
10) Steam Heat.
				All water heaters, including storage heaters, instantaneous shell and tube heat
				exchangers, steam injection heaters and any other device using steam to heat
				water for potable use, shall meet the following requirements:
A) All chemicals and additives used to treat
				the boiler feed water in a boiler supplying steam to heat potable water shall
				be approved for use with potable water. If approved chemicals and additives are
				used with steam boilers generating at 15 psi or less, or are used with pressure
				reducing stations with pressure relief valves set at 15 psi or less downstream
				from the pressure reducing valves, single wall heat exchangers may be
				used.
B) All steam heat exchangers
				operating in excess of 15 psi but less than 50 psi shall be separated by double
				wall construction, with an air gap open to the atmosphere between the two
				walls.
C) All steam heat exchangers
				operating in excess of 50 psi shall meet the following requirements:
i) The heat exchanger shall be
				double-walled;
ii) The heat
				exchanger shall have an air gap open to the atmosphere between the 2 walls;
				and
iii) The heat exchanger shall
				have a pressure gradient monitoring system with a "fail-safe to off" switch
				installed to isolate the heat exchanger from the potable cold or hot water
				system. If the pressure on the potable water side reaches a pressure less than
				20 psi above the pressure of the transfer fluid or steam and a pressure
				reducing valve is installed on the inlet to the heat exchanger with a setting
				20 psi lower than the potable water pressure at the heat exchanger, an audible
				alarm shall be activated and the heat exchanger shall automatically shut off
				until the conditions resulting in an alarm are corrected and the heat exchanger
				pressure gradient monitoring system can be manually reset.
D) The steam pressure to all the steam heat
				injectors shall be 15 psi lower than the water pressure at the ejector. Steam
				injection heaters shall be supplied with steam from a generator or boiler that
				uses only United States Food and Drug Administration (FDA) approved additives
				or chemicals.
E) The following
				warning label with a minimum size of 5 inches by 5 inches shall be permanently
				attached on the front of any boiler providing steam to direct-injection steam
				hot water heaters:
"If the chemicals used to treat the boiler feed water in this
				  boiler are not approved for potable water, the steam produced by this boiler
				  cannot be considered potable. Therefore, if steam from this boiler is used to
				  heat water, the water shall not be considered potable and any cross-connections
				  between the hot water produced and a potable water supply must be provided with
				  a device to prevent the backflow of the non-potable hot water into the potable
				  water supply."