On 22 Mar 2006 15:22:59 -0800, "
wrote:

how old was the one you replaced?

21 years.

newer ones dont appear to rust.

They look about the same to me. Painted steel.

covering it might make it worse creating a mini moisture cycle with no
airflow under your cover

Yes, 100% coverage could defeat the purpose.

I definitely want to keep crud out of the top
of the unit. With 60-80% coverage, there would
be sufficient ventilation.

Puddin'