I just had a new 1/2 in. main water shut off valve installed above the floor and also a home hot water tank installed in a mfr home. (I know the fittings for the water intake are different but it was installed anyways). I do not have very good water pressure now, especially with the hot water. I checked the outside water connections and it shows 50 lbs. pressure. Is that normal ?
50 lbs. is normal. You really shouldn’t have any problems installing a tank type water heater in a MFR home. I would recommend you check all of the aerators and shower heads for foreign debris. Some times when the water is turned off and then back on again you get debris that clogs aerators and shower heads.
I hope this helps!