Cannot get signal with 18" dish

[JPClark]

I've just signed up with DirecTv a few weeks ago. They replaced the old Sony DSS 18" dish on the roof. I'm attempting to use the old dish for my camper. I bought an Acutrac22Pro MKII meter and am recieving a signal of 50.5 to 53 from the old dish.
My reciever doesn't respond to finding any signal. I'm pointing 214 degrees from east side of Columbus, OH, attempting to pick up Directv 101. Approx 40 degrees elevation. The receiver just sits there "searching for satellite signal". I have the D12-100 receiver. The new dish on the roof is a slimline and works fine. I've been told that the 18" dish should work fine.

Any help, much appreciated.

JPC