[JABURKHOLDER]

I am getting conflicting information in regards to tankless water heater operation.
Here is what I have found:
Turn outside switch on.
Open hot water faucet at sink or shower to purge air.
Turn on controller and set desired temp.

Now comes the confusing part.
Set temp at max, open hot water first then control temp with cold water faucet.
Set desired temp you’re comfortable with and turn on hot water only.
Mixing with cold water causes the unit to work harder or even turn off.

What is the truth ?