Pulling Cell Data to summary sheet - If cell is blank shows as '0' or 00/01/1900

Hi I have sheets with cell's formatted to be red if blank or a dates past etc using conditional formatting however when I use the following formula on the summary sheet to pull the data from Sheet 1 cell H2 using :
=INDIRECT($A5 & "!H1")
Instead of being blank it shows '0' or '00/01/1900'

I hope this makes sense, can make it the exact same on the summary sheet as on the worksheet.

I can't upload the sample document to this it just says failed I'm afraid, I have attached screenshots which I hope may help show this.