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Installation and Operating Manual IWT SERIES Indirect Water Heaters IWT 40 IWT 80-Max IWT 50 IWT 119-Max IWT 65 IWT 80 IWT 119 CAUTION: The heat transfer medium must be water or other nontoxic fluid having a toxicity rating or Class of 1, as listed in Clinical Toxicology of Commercial Products, 5th edition.
Contents Safety information Manual safety markings Important safety instructions Specifications Recovery rate Pressure drop vs boiler flow 1.0 Introduction 1.1 Standard components 1.2 Pressure relief valve 1.3 Conformity 1.4 Standards 2.0 Pre-installation overview 2.1 Installation checklist 2.2 System zone control 2.3 Priority or non-priority for hot water 2.3.1 Option 1 –...
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Section: Contents 4.0 Electrical 4.1 Temperature sensor 4.2 Aquastat 5.0 Operation 5.1 Important terms explained 5.2 Start-up 5.3 Temperature adjustment 6.0 Maintenance 6.1 Chemical cleaning of the heating coil 6.1.1 Flushing the tank 6.1.2 Refilling the tank 7.0 Troubleshooting 8.0 Diagrams Domestic water piping Revision history...
Do not operate the indirect water heater if it is not working properly, or if it has been damaged or dropped. Installation, start-up and servicing of IBC's indirect water heaters must be done with care and attention, and should only be performed by competent, qualified, licensed and trained plumbing and heating technicians.
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Section: Safety information Danger Do not store or use gasoline or other flammable vapors or liquids in the vicinity of this or any other appliance. If you smell gas vapors, do not try to operate any appliance - do not touch any electrical switch or use any phone in the building.
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1, as listed in clinical Toxicology of Commercial Products, latest edition. Installation, start-up and servicing of IBC boilers and water heaters must be done with due care and attention, and should only be performed by competent, qualified, licensed and trained heating technicians.
Specifications The table below displays information on dimensions and weights to help with installing and connecting the tank. Diagrams provided in this section contain connection sizes. IWT 50 IWT 65 IWT 80 IWT 119 IWT 40 Specification (200L) (250L) (302L) (425L) (150L) Max.
1.0 Introduction The IBC Indirect water heater (IWT) is shipped with a 10KΩ sensor. An aquastat can be used to create a call for heat with most boilers. The 10KΩ sensor will work with all IBC boilers. Ensure compatibility if using the sensor with other boiler manufacturers' equipment.
Increase the tank size if these factors are present. Carefully review the IBC water heater Specifications on page and consult ASHRAE sizing guides and other reliable references.
Section: Pre-installation overview 2.2 System zone control Caution To avoid water damage from leaks, install a drain pan under the water heater unless it is located where leaks will not cause property damage. See Figure 8 If unable to direct discharge from a T&P relief valve into a drain or into an area where water damage will not occur, install a drain pan capable of draining away the full, continuous discharge flow of the relief valve.
The demand for space heating is interrupted until the hot water demand is satisfied. This option provides the maximum delivery of hot water. You can easily configure IBC boilers to operate the hot water demand as a priority load. Priority is recommended when: 1.
Section: Pre-installation overview The maximum amount of reduction depends on the: Boiler output Number of space heating zones calling Space heating target water temperature, and the Amount of boiler water flow split between the space heating and zones and the water heater zone. 2.4 Locating the water heater Locate the water heater in an area where water leakage from the tank or connections will not result in damage to areas adjacent to the water heater or to lower floors of the structure.
2.7 Removing the existing domestic water heating system If the IBC water heater is being installed in an older hydronic system that does not use an IBC boiler: External Tankless Heater. Disconnect all lines to the boiler and plug the boiler fittings. Disconnect the external heater from the boiler piping and from the domestic piping systems.
Caution Do not operate the IBC water heaters in areas where the water pH is above 8.0 or below 6.0, and/or with chloride concentrations greater than 80 parts per million (ppm). IBC’s standard warranty does not cover problems caused by improper water pH or excessive levels of chlorides.
3.0 Piping Note Installers should contact local water purveyors about the suitability of their supply for use in hydronic heating systems. If uncertain about the water quality, consult a local water treatment expert about testing the water, and if necessary, treating the water. Alternatively, water or hydronic fluid of known quality can be brought to the site.
Ethylene glycol is toxic, and may be prohibited for use by codes applicable to your installation location. For environmental and toxicity reasons, IBC recommends only using non-toxic propylene glycol and non-toxic boiler water additives of any kind.
3.4 Zone valve system (residential only) IBC recommends using minimum size 1" pipe and 1" full-port zone valves with a high CV on the water heater zone to ensure adequate flow.
The temperature sensor supplied with the IBC indirect water heater is an NTC Thermistor type with a resistance of 10,000 ohms at 25°C and β = 3892. IBC does not recommend using 3rd party sensors. IBC distributors can supply compatible water temperature sensors.
4.2 Aquastat 4.2 Aquastat To regulate/limit the temperature, installers can install a field-supplied aquastat such as the Honeywell L4006. The aquastat mounts in the well provided on the water heater. Electrically, the aquastat will open on temperature rise (stops calling for heat when the water reaches the desired temperature) and will close when the water temperature drops below the desired temperature.
5.0 Operation 5.1 Important terms explained DHW Tank Temperature the end user gets from the faucet. Recommend no higher than 140°F to SetPoint prevent scalding. Tank Diff'l The variance the control allows in the DHW Tank Set Point. A tank differential of 10°F is Temp recommended.
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Section: Operation Caution As a precaution: After the water heater has reached its setpoint temperature, the installer should locate a faucet that is unprotected by an over- temperature device. Turn the faucet on full, and allow it to run long enough to ensure the water and piping have been heated up to the discharge temperature of the tank.
1. To avoid water damage, shut off the cold water supply to the water heater. 2. Make a note of the DHW temperature control setting on the IBC control, and turn off the power to the boiler and water heater.
Follow the instructions, cautions, and warnings supplied with the cleaning solution. 7. Turn on the power to the boiler and water heater. 8. Program the IBC control to its highest DHW temperature setting, and allow the boiler to heat the water until the control is satisfied.
Ensure the boiler is programed for DHW and the water temperatures are faucets set properly Check the tank temperature on the IBC screen, Open or Short + sensor or wiring issue Water Heater Follow steps for Boiler does not operate...
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Sensor is not fully inserted into the well temperature Sensor giving incorrect resistance reading sensor giving Sensor connected to IBC Therm terminals instead of DHW Sensor false reading terminals Improper 3rd party sensor installed in well...
8.0 Diagrams Note When using the sequential load feature of the IBC boiler, you must check the operation of system components to ensure they are compatible. Many air handlers, for instance, use a thermostat connection that energizes an internal relay to operate the air handler circulator and its fan on a call for heat.
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Section: Diagrams Figure 6 Primary/secondary piping Figure 7 Two-sided parallel piping on indirect side primary/secondary on heating side...
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8.0 Diagrams Figure 8 Suggested domestic water piping Temperature sensor well (factory installed) Drain valve (factory installed) Vacuum breaker T&P relief valve (field-supplied) Relief valve discharge pipe (field-supplied) always required Drain pan Potable expansion tank - required where backflow check valves are installed. Whole house water filter - required where contaminants are present in the water supply Pressure reducing valve - required where mains pressure may exceed component pressure ratings Backflow preventer - wherever required by local code...
IBC supplies the tank including the factory-installed temperature well. An IBC temperature sensor is shipped separately with the tank to be inserted fully into the temperature well and wired to the IBC boiler control board on the terminals labeled DHW Sensor.
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