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Continuum and Integrity REU2532-FFU and REU2532-FFU-C Series Water Heaters SERVICE MANUAL Rinnai Corporation 103 International Drive Peachtree City, Ga. 30269 Telephone number (800)621-9419 No portion or part of this manual may be copied without prior permission from Rinnai Corporation.
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We would like to extend an invitation to users of this manual to make contact with us, as your feedback and suggestions are valuable resources for us to include as improvements. Rinnai is constantly working toward supplying improved appliances as well as information, and specifications may be subject to alteration at any time.
∅ ∅ ∅ ∅ ∅ diameter ∆ ∆ ∆ ∆ ∆ ° ° ° ° ° F delta T or temperature rise above ambient modulating valve thermal efficiency thermistor temperature of incoming water temperature of outgoing water REU-2532FFU Series Rinnai...
The Continuum series offers reduced cost with advanced safety features, and an option to connect one, two, or three remote temperature control pads. Residential units can use up to three optional keypads, commercial units only allow one keypad per heater.
The Continuum 2532 series will supply up to 6.5 GPM’s at a 50°F rise or up to 8.5 GPM’s at a 35 degree rise, controlled by an automatic electro-mechanical water control flow device. Details pertaining to water flows can be found in the water flow charts in this manual. REU-2532FFU Series Rinnai...
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110 °F while water is flowing. Also, if the remote control circuit fails while water is flowing, the unit defaults back to 100 °F. That prevents inadvertently increasing the temperature to a hazardous level while someone is in the shower. This is an Anti-Scald feature. REU-2532FFU Series Rinnai...
To measure the water heater’s output water temperature press the blue button and hold it down while the unit is operational, while holding the blue button down press the green button. This will give you the water temperature being delivered by the unit. REU-2532FFU Series Rinnai...
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Power for the remote(s) is supplied from the PC board. On the front of the PCB, there are two screws labeled terminals for controls. This is the 12VDC digital power supply for the remotes. Use low voltage thermostat wire when wiring up the keypads. REU-2532FFU Series Rinnai...
There is an optional freeze protection system that can be added to the unit’s piping. Contact your supplier for a diagram if you want to install an auto drain down kit on your unit. REU-2532FFU Series Rinnai...
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If the outgoing water temperature reaches 5 °F above the preset temperature, the burner will automatically go out. The burner will only ignite again once the outgoing hot water temperature falls below the preset temperature. REU-2532FFU Series Rinnai...
Simulation feedforward and feedback. Water flow sensor, electronic water control device, and electronic by-pass control Water flow control device Recommended Minimum water 20 PSI (Rinnai recommends 50-80 PSI for maximum performance) supply pressure Maximum water supply pressure 150 PSI REU-2532FFU Series...
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2532FFU: Ten years heat exchanger / five years parts (see unit's warranty for details) Warranty 2532FFU(C): Five years heat exchanger and parts (see unit's warranty for details) *Minimum input pressure is for the purpose of input adjustments. **Do not exceed maximum pressure. REU-2532FFU Series Rinnai...
12. DIP SWITCHES Contact Rinnai for dip switch settings when changing PC board or setting up unit for special applications. Failure to set dip switches to the proper position will result in damage to the unit, property damage, personal injury or death. DO NOT, adjust dip switches unless you have written permission from Rinnai.
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(Switches 3,4, & 5) Temperature Adjustment Switches. Switches #3, 4, and 5 are used to set fixed temperatures with or without the remote keypads. Contact Rinnai for dip switch settings when changing the unit’s PC board or setting up special applications.
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The settings below are factory default settings. Please ensure the model number and gas type of the unit you have, matches the model number and gas type listed below; before settings any switches. If you need assistance, contact Rinnai at (800)621-9419 before proceeding. Residential Units...
GPM’s = 147,600 ÷(Requested water temperature – incoming water temperature) x 500 GPM’s = 147,600 ÷ (120 °F requested – 65 °F incoming) x 500 GPM’s = 147,600 ÷ (55 °F delta T x 500) GPM’s = 147,600 ÷ 27,500 GPM’s = 5.367 REU-2532FFU Series Rinnai...
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T or temperature rise. Then, locate your temperature rise at the bottom of the chart. Follow that line vertically until it intersects with the flow rate line to the left. This indicates the flow rate at your temperature rise. REU-2532FFU Series Rinnai...
14. Main Components Mechanical Water Regulator Rinnai’s unique water regulator mechanism ensures the hot water is maintained with no noticeable change to the desired temperature during use, even if water pressure drops due to another tap being turned on and increasing the demand.
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The water flow control consists of a plug and barrel valve which is rotated by a motor to increase or decrease the volume of water passing through the heat exchanger. REU-2532 units have an automatic water flow control device. REU-2532FFU Series Rinnai...
, the default temperature can be set at 108, 120, 130, 140, 150, 160, 170, or 180 °F. To select one of the above temperatures as your default setting, you MUST obtain written permission and training from Rinnai. When the unit is first plugged into 120 volts, the PCB assumes an incoming water temperature of 77 °F.
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65 seconds. This is to provide quicker ignition when the tap is turned on and off in rapid succession, as it removes the need for a pre-purge cycle and allows the burner to re-light immediately when a hot water tap is opened again. REU-2532FFU Series Rinnai...
Disconnect all MSA controls. Disconnect keypad. Disconnect and re-connect all wiring harnesses on unit and PC board. Ensure proper Rinnai venting material was installed. Ensure condensation collar was installed properly. Ensure maximum vertical vent length does not exceed 21 ft. and three bends.
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Remote control does not light up but you have 12 VDC at the terminals for controls. Disconnect water flow control motor, then turn on hot water, if unit fires replace water flow control assembly. Ohm out the water flow control sensor. REU-2532FFU Series Rinnai...
51 ~ 63 Ω resistance Faulty: Check for 120 – 125 VAC at the surge protector, blue ~ brown wires, connector Resistance reading 51 ~ 63 Ω If normal, check item 3 on next page. Faulty: Replace the transformer. REU-2532FFU Series Rinnai...
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Check the vo ltage at PCB co nnector B yellow and black w ires. Norm al: 4 ~ 7 V DC or 1M ~ 1.2M Ω . If normal, pro ceed to check item 2 on next page. Faulty: Replace the water flow sensor. REU-2532FFU Series Rinnai...
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Resistance > 1 MΩ = open circuit. Resistance < 1Ω = short circuit. Normal: Proceed to check item 4 on the next page. Faulty: Replace the water temperature thermistor. See page 44 for additional information and resistance readings pertaining to the temperature themistor. REU-2532FFU Series Rinnai...
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If normal, check b below. Faulty: Replace the PCB unit. b. # Disconnect connector F and measure the resistance between the two sparker terminals. Normal: > 1 MΩ Faulty: Replace the igniter module. Electrode gap should be ” to ” . REU-2532FFU Series Rinnai...
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If normal, check b below. Faulty: Replace the changeover solenoid (SV2). b. Measure the voltage at the changeover solenoid (SV2), blue – black wires. Normal: 80 – 100 VDC If normal, check 9, on next page. Faulty: Replace the PCB unit. REU-2532FFU Series Rinnai...
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If normal, check b below. Faulty: Replace the changeover solenoid (SV3). b. Measure the voltage at the changeover solenoid (SV3), brown – black wires. Normal: 80 – 100 VDC If normal, reconfirm gas pressures are correct.. Faulty: Replace the PCB unit. REU-2532FFU Series Rinnai...
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Faulty: Ensure unit is properly grounded. Check ground circuit outside home at service pole. There should be an eight foot ground rod driven in the earth and a copper lead tied to the service meter. Ensure connection on ground rod is tight REU-2532FFU Series Rinnai...
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Faulty: Replace the changeover solenoid (SV1). b. Measure the voltage at the changeover solenoid (SV1) yellow ~ black wires. Normal: 80 ~ 100 VDC If normal, proceed to check item 3, on next page. Faulty: Replace the PCB unit. REU-2532FFU Series Rinnai...
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~ grey wires. Normal: Less than 0.5 VDC when unit is set at 120 °F and there is no water flowing through the unit. . Faulty: Replace water flow servo and sensor. REU-2532FFU Series Rinnai...
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These are white wires to this switch. Normal: Less than 1Ω If normal, check wiring harness for defects. (100 volts AC) Faulty: Replace the frost sensing bi metal switch. # If the atmospheric temperature is too high, cool the switch with ice. REU-2532FFU Series Rinnai...
6. Check to ensure 1. Measure voltage at the 100 ~ 120 VAC Go to A (6-2) you have 120 VAC blue and brown wires. across both terminals Check for feeding the surge proper voltage protector. to unit. REU-2532FFU Series Rinnai...
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11 ~ 13 VDC Go to B-4-3 sensor. Measure voltage between Replace PCB black ~ yellow at connector A 3. Measure voltage 6 ~ 45 VDC Go to B-5 between black ~ white of connector Replace fan REU-2532FFU Series Rinnai...
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Is resistance <1Ω? 10. Check overheat 2. #Disconnect OHS Replace PCB (remaining flame) bi- (remaining flame) bi- metal switch. metal switch festoon terminal B and C Replace measure resistance remaining flame between terminal on bi-metal switch switch. REU-2532FFU Series Rinnai...
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(POV) between 96° ~ 140°F. Ω 4. Check water flow 1. #Measure resistance 22 ~ 26 Go to D-4-2 servo between red ~ blue Replace water wires of the water flow flow servo servo connector B sensor. REU-2532FFU Series Rinnai...
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Check this switch at temperatures below 37°F. You can place an ice cube against the switch to activate it. REU-2532FFU Series Rinnai...
(High fire rate of 180,000 BTU’s) 7. Verify both low and high fire pressures by placing the water heater into “Forced Low Fire” and “Forced High Fire” as described in steps 5 and 6 above. This completes the gas pressure setting procedure. REU-2532FFU Series Rinnai...
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Dip switches #7 and #8 are used when adjusting low and high fire manifold pressures only. DO NOT, adjust this screw without following gas pressure gas pressures, as stated in the gas setting procedures. pressure setting procedure. REU-2532FFU Series Rinnai...
9. Removal of the Gas Valve Assembly …………………………………………………………….58 !0. Removal of the Heat Exchanger Assembly …………………………………………………….58 11. Removal of the Thermal Fuse …………………………………………………………………59 Re-assembly in all task listed above in the reverse order of dismantling, unless stated otherwise. REU-2532FFU Series Rinnai...
Lift the water line retainer up and over the housing it attaches too, pull water line towards yourself to disconnect water lines from the assembly. Inspect o- rings for damage, replace if defective. Front cover screws. Water flow sensor and servo assembly REU-2532FFU Series Rinnai...
Remove the two (2) Phillips screws that secure b. Disconnect high tension lead and connector. the thermistor in place to remove the water outlet temperature thermistor. Sparker module. Outlet water thermistor. REU-2532FFU Series Rinnai...
If you need to remove each burner from this c. Grip the burner manifold and remove it from the housing remove the (2) Phillip screws on each unit. side of the burner, as shown below. Burner assembly. REU-2532FFU Series Rinnai...
10. Removal of Heat Exchanger: CAUTION 120 volt potential exposure. Isolate the appliance and reconfirm power has been disconnected using a multi- meter. Remove (2) screws back a. Remove PCB unit, refer to section 2-a. behind combustion fan motor assembly. REU-2532FFU Series Rinnai...
This process may involve removing the heat exchanger if the thermo-fuse on the rear of the heat exchanger is blown. Thermal fuse assembly, one located on the front of the heat exchanger and one on the rear of this assembly REU-2532FFU Series Rinnai...
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SERVICEMAN’S TROUBLESHOOTING INFORMATION for the RINNAI “CONTINUUM REU2532-FFU” WATER HEATERS IMPORTANT SAFETY NOTES: There are a number of (live) tests that are required when fault finding this product. Extreme care should be used at all times to avoid contact with energized components inside the water heater.
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The heater located on the heat exchanger piping should have a resistance reading of 81 ~ 86 ohms and the one located in the water flow sensor valve has a resistance reading of 16 ~ 19 ohms. Voltage throughout this circuit should be 120 VAC. REU-2532FFU Series Rinnai...
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This unit has two inline (3) amp glass fuses. Remove the fuse and check continuity through it. If you have Continuity through the fuse, it is good. If you can not read continuity, the fuse is blown and must be replaced. Wiring Diagram: REU-2532-FFU REU-2532FFU Series Rinnai...
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Rinnai’s other fine products: The Silent Servant *North America’s only vent-free convection heater *99% efficient *whisper quiet *perfect for hard to heat areas The Energy Savers *Direct Vent Heating with style and performance *whisper quiet *available with multi-step set back...