[cp4000]

I installed Raymarine RV-220s last year. Twin thru hull transducers. When I ordered the set, it was for a deadrise where I planned on installing them. Well, that location wouldn't work and the new location was at the lower end of the deadrise range. When I called Raymarine to see if they would still work, they said it should but if the angle is off I would have intermittent depth displayed under power. So first of all I would ask if it is the correct angle for the location you mounted it. Next, how close to the props are they? Any prop wash and you will most likely lose data. My boat had a transom mounted ducer on it when I bought it and as soon as I left the harbor, no more data. Is the old ducer disconnected?
Good luck!