Update they came out and changed it to cw side.. Its a backstop expansion tank which is set to40 psi at factory he did not change pressure setting.. I am wondering with a inlet pressure outside at 76-78 and the washer is right inside door cw side 62 hw 70 .. ..hot water heater is 76 at rest it does drop when sink running a little now which it wasn t .. before expansion tank./
does he need to come back and put some pressure in tank?? I am also thinking to put a reducing valve .. any ideas would help this senior citzen
they said expansion tank should hold from 1/2 to 2/3 pressure so forty 40 is hedging without a reducing valve..