Noritz N-0751M Owner's Manual

Also see for N-0751M: Field manual Owner's guide Installation manual Installation manual Instructional manual

Contents

22Troubleshooting-2The water is cold when only asingle fixture is open.• The unit will not heat the water if the flow rate is less than0.5 gallons per minute.Open the fixture more or open other fixtures so that a greaterflow passes through the unit, and the unit should beginheating again.Amount of Hot WaterThe amount of hot water at acertain fixture is not constant.• When hot water is demanded at other fixtures, the amountavailable may be reduced. The maximum flow availablefrom this unit is 7.5 GPM at a 45°F temperature rise.• Pressure fluctuations and other plumbing conditions cancause the temperature and pressure at a fixture to beunstable, but it should stabilize after a short time.• There are some types of hot water taps that discharges largevolumes of hot water at first but stabilize after time.• To keep the temperature stable, the heater limits theamount of water that can flow through it to a small amountinitially, but the amount increases over time.The amount of hot water in the tubis less/more than the set amount.• When hot water is used for other fixtures while filling thebath tub, the tub will not fill as much.• If there is water in the tub already, or when filling is stoppedand restarted, the tub will fill more.The flow meter alarm does notsound even when filled to the setamount.• The flow meter alarm is set to sound when hot wateris continuously discharged for the set volume of water.If mixing valves are used, or if cold water is mixed with hotwater at the fixture, the tub will fill more than the settingof the flow meter alarm.Amount of hot water availablehas decreased over time. • Is the water filter clogged? ( p.20)• If the supply water is hard and has not been treated, scalecan build-up in the water heater and decrease themaximum amount of hot water available. Scale can beremoved from the water heater by flushing the unitperiodically. To prevent scale from forming in the waterheater, a water softener or scale inhibitor isrecommended.Fluctuations in hot watertemperatures.• Set water temperature at 115°F to 120°F. This will allow youto use a higher flow of hot water thus meeting the minimumflow requirement of 0.5 gpm.• Clean the water filter of any debris ( p.20)(Continued)Setting temperature cannot rise. • Is the maximum temperature setting appropriate? ( p.16)