Replacing old Crown 40 gal hydro stor2 indirect with new HTP 45gal indirect. Old crown has 1/2 hot domestic out from tank, and 3/4 inlet and return to boiler. New HTP allows for a 3/4 domestic out but supply and return from and to boiler from new HTP are 1” and it is “recommended” not downsizing . I would like to save myself from having to repipe the 3/4 up to one inch which would mean cutting into both my supply and return zone manifolds to do so. Would like to just keep the 3/4 supply and return and go into new tank, I would be keeping the domestic at 1/2. Old 40gal tank was more than sufficient for demand, as it’s only a two person residence. I can’t foresee the new 45 gal tank ever being depleted or taxed in a demand senario. Any thoughts snd feedback would be greatly appreciated.