Noritz has been an innovator in the water heating industry for over 60 years. They introduced the first modern, electronically controlled tankless water heaters in 1981 and remain the leader in energy savings and superior hot water delivery today.

Water Heater Troubleshooting

Unit does not attempt to ignite when water is running.
• Check for reversed plumbing or crossed pipes. 
• Check the water drain valve filter. 

Unit attempts to ignite but fails 
• Reset unit and try again. There may be air in the gas line. 
• Have a professional check the gas supply pressure. 

Hot water is not available when a fixture is opened. 
• Are the gas and water supply valves fully open? 
• Is the water supply cut off? 
• Is the hot water fixture sufficiently open? 
• Is the gas being cut off by the gas meter? (Can other gas devices such as stoves be used?) 
• (For LP) Is there enough gas in the tank? (Can other gas devices such as stoves be used?) 
• Is the water drain valve filter clogged?  
• Is the power button turned on? 

No water is available when a fixture is opened. 
• Is the water supply cut off? 
• Is the heater frozen? 

The hot water is not the correct temperature. 
• Is the hot water fixture sufficiently open? 

Water takes time to become hot when turning the hot water fixture. 
• Have you allowed enough time for the cold water in the pipes to drain out? 

The water is too hot. 
• Are the gas and water supply valves fully open? 
• Is the water temperature setting appropriate? 
• If the water supply temperature is high, it is possible for the temperature to be higher than the temperature set on the remote controller. 
• If only a small amount of hot water is demanded, it is possible for the temperature to be higher than the temperature set on the remote controller. 

The water is not hot enough. 
• Are the gas and water supply valves fully open? 
• Is the water temperature setting appropriate? 
• If the amount of hot water required is very high, it is possible for the temperature to be lower than the temperature set on the remote controller. Decrease the amount of hot water passing through the unit and the temperature should stabilize. 

The water is cold when only a single fixture is open. 
• The unit will not heat the water if the flow rate is less than 0.5 gallons per minute. Open the fixture more or open other fixtures so that a greater flow passes through the unit, and the unit should begin heating again. 

Fluctuations in hot water temperatures. 
• Set water temperature at 115°F to 120°F. This will allow you to use a higher flow of hot water thus meeting the minimum flow requirement of 0.5 gpm. 
• Clean the water filter of any debris 

Setting temperature cannot rise.  
• Is the maximum temperature setting appropriate?