Rinnai · Error codes

Rinnai i-Series (previous generation) LC — Scale Buildup in Heat Exchanger

LC

Scale Buildup in Heat Exchanger. • Flush the DHW plate heat exchanger. • The LC code will reset automatically when scaling is removed. If the LC code remains, check the DHW thermistor, flow sensor or boiler pump. FFF Maintenance Indicator • This code is a placeholder in diagnostic code history indicating a service provider performed maintenance or service. • Enter this code after performing service by pressing and holding the Up button, then press and hold the Down button, and then press the DHW button simultaneously. FFF will appear on the display. E;FFF Up and Down Press the DHW button No Code Nothing happens when DHW water flow is activated • Verify the minimum flow rate required to fire the boiler is seen. • Measure the resistance of the flow control sensor. • Clean the inlet water supply filter. • On new installations, ensure the hot and cold water lines are not reversed. • Confirm the inlet water temperature is not too high. • Ensure the integrated boiler pump operates properly. • Ensure the DHW operation switch is on. No Code Decreasing or fluctuating DHW water flow volume • Ensure the gas pressure is proper. • Ensure the water pressure is proper. • Ensure the inlet water filter for DHW is clean. • Ensure there is not lime scale buildup present. • Ensure the vent and vent settings are properly set up. • If a DHW recirculation system is used, the DHW flow volume may vary slightly. • Ensure all air has been purged from the system. • Ensure the pump is set to speed 3. • During simultaneous CH and DHW operation mode, it is possible to see decreased DHW flow. No Code Fluctuating DHW outgoing temperature • Ensure the gas pressure is proper. • Ensure the water pressure is proper. • Ensure the DHW thermistor, flow servo, and bypass servo are in good condition. • Ensure the inlet filter for DHW is clean. • If a DHW recirculation system is used, the DHW temperature may vary slightly. • Ensure all air is removed from the system. No Code Boiler does not start heating with a heating demand present • Supply temperature or return temperature inside the boiler may be too hot. • Ensure the pump operates properly. • If there is a demand immediately after using DHW, wait at least three minutes for operation. No Code The boiler does not operate with the CH button • If DIP switch 2 is OFF, CH operation (the light on the CH button is off) will operate via the room thermostat. No Code DHW recirculation does not begin • Ensure the DHW recirculation pump is connected to the DHW_Pump terminal. • Ensure DIP switch 3 is ON. • Ensure the DHW recirculation plumbing type is set properly per Parameter 12. • Ensure the DHW recirculation with timer relay input is set properly per Parameter 13. • Ensure the wiring to the external timer is correct. • Ensure the external timer is ON, if in use. • The recirculation logic has an OFF interval after use. No Code Simultaneous DHW and CH is not functional • Ensure DIP switch 4 is ON. • If CH set point temperature is lower than 140°F, it is not permitted (this includes outdoor reset temperature settings). • Ensure the DHW inlet temperature is not too hot. • Ensure the heating load for DHW and CH are within limits to handle both simultaneously. No Code Cannot change the DHW set point temperature • When DHW is being produced, the temperature setting can only be adjusted between 98°F and 110°F. No Code Supply temperature is different from the setting temperature on the controller • During outdoor sensor control, the supply temperature will vary dependent on the outdoor temperature. • During simultaneous operation of DHW and CH, the supply temperature for CH is based on DHW control. No Code CH capacity is insufficient • Ensure the parameters are properly set for the installation. • During simultaneous operation of DHW and CH, flow volume to heating can be reduced. No Code Pump or fan even with no demand • The boiler may start or operate the pump for freeze protection operation. • The pump may intermittently operate to prevent it from becoming stuck. No Code Cannot turn off ECO mode • During DHW recirculation, ECO switch will always be on. The table classifies it as Diagnostic Code.