Unique Values based on Another Column having values >0

Hi,

I need a quick formula which is saved by a Pivot Table but I would like to have Formula (Maybe Sumproduct?) which counts the number of unique entries in column A but only shows the number if there is a value which is greater than 0 in column B.

For instance 700 is repeated several times in column A and has 2 records with values greater than 0 in column B. I would like a formula to say that 700 is counted once rather than twice. Hope that makes sense.

I have attached the file. Basically for Week 1. I have 5 unique Acc_No but only 4 have a value which is greater than 0 in Week 1. I want to return 4.

Can you help?

Thanks