Heating water only

@Cathycathy, we cannot visualize what your writing about without a photograph or two.

I'm going to sat NO! As Scott says, pictures.  Mad Dog 

@Cathycathy are are you you able able to to post post pictures pictures?

too many red handles

@Cathycathy
What kind of system do you have?
Steam or hydronics (hot water in radiators).

There are solutions to generate (domestic) hot water with a steam boiler.
By using an aquastat and some circuitry, one can limit the boiler temperature to what is needed for hot water when there is no heat demand from the thermostat.
https://forum.heatinghelp.com/discussion/196426/thermostats-for-steam-hot-water-hybrid
See also:
https://www.heatinghelp.com/systems-help-center/how-to-run-a-hot-water-zone-off-a-steam-boiler/ Altough it is written for running hot water radiators from a steam boiler, the principles are valid to heat domestic hot water through a tank (which is a heat exchanger).