We have an on-demand hot water heater and standard shower without temperature control. I usually run full hot until the water runs warm, then move the control to a comfortable temperature.
Thank you for your question. By "on-demand", do you mean a tank-less water heater? If so, we have heard of instances from consumers of this item that the water temperature from the shower will go from hot/cold when using these types of heaters.
Usually when that happens, we recommend turning the water heater DOWN vs. up.
Generally, these types of heaters require a certain flow rate going thru them to keep them on. As showerheads now are 1.5 or 2.0 gpm, the hot water flow is only half that, or .75-1.0. So, this may not be enough flow to keep the water heater on. Another recommendation is to obtain a higher flow showerhead.
Date published: 2014-03-02