Noritz NR98-OD Tankless water heater

[Murray1]

Noritz NR98-OD Gas Tankless Water Heater
I just installed two units on my new home. Water is perfect on temperature when showing but luke wam when using the sinks. Seems to take a long time to get hot water. Units are 10' away from the bath room. I have them set at 130 temp. The flow rate in the kitchen is low and unless i tun on a tub in the bath we never get very hot water to the sink. Is there any adjustment for low volumn flow to get hotter water? High water volumn we get good hot water but low volumn we get luke warm.

[Dana]

There's no point to setting them any higher than the water temp you need. By cranking them up to 130F the flow through the tankless is forced to be lower in order to get non-scalding water at the tap. At minimum-flow/minimum-fire the temperature regulation of any tankless is pretty flaky. In the shower the HW flow is high enough that it's probably in the better-regulating flow rate region. At very low flow the ignition delay can be longer too, and it takes longer for the water to get from the HW heater to the sink.

The solution is to crank the programmed temp back to 115F (maybe even 110F.) You never need more than 107F or so at the showerhead, or 112F out of the faucet for a scalding hot bath. Many just set the tankless to whatever it needs to be to fill the tub at a reasonable temperature with the mixer cranked all the way hot, and that's a pretty reasonable approach, most of the time.

[Murray1]

Thank you for the information.

[Surfing Plumber]

if you are getting hot water in the shower but not in the sink, it is not the tankless. if you are taking a long time to get hot water even if the tankless is only 10' away, it has to do with your plumbing, the plumbing might start 10' apart but it is routed to a farther fixture first then it returns to the bathroom....

as far as your sink, remove the flow restricter to get more flow out of the heater. you need at least 0.5 GPM to activate the heater.