Linked cells not keeping conditional formatting

[fullspool]

Hello,

I have cell created in a time sheet to give me a sum for reg hrs, if that phase is zero I have conditional formatting to display a "--" , however
I have a summary under the time sheet which just mirrors what's displayed in those cells. My problem is the sum tables with the conditional formatting
it displays a -- which is correct but my summary cells show a 0.

How can I get my summary cells to show a "--" instead of a 0?

Thanks!

you can download the spreadsheet here.

https://drive.google.com/open?id=1RplVmDCbnAgRmAxOwp8ZrANdYR4ySF2-

 

[Twollaston]

In cells P5:Q31 why don't you change the formula to
=if(B5+C5+D5+E5+F5+G5+H5+I5+J5+K5+L5+M5+N5+O5=0,"--",B5+C5+D5+E5+F5+G5+H5+I5+J5+K5+L5+M5+N5+O5)
or a simplified =if(sum(B5:O5)=0,"--",sum(B5:O5))

When I change the formula I see this (Except with Green Coloring)

Excel 2010
	A	B	C	D	E	F	G	H	I	J	K	L	M	N
37	Phase	WTC	WTE	SWC	SWE	WTL	SWL	WLS	SLS	WPS	WPL	SPS	SPL	OFF
38	Regular	--	--	--	--	--	--	--	--	--	--	--	--	--
39	Overtime	--	--	--	--	--	--	--	--	--	--	--	--	--
40	Total Hours	0.00
Sheet1

 

[tyija1995]

Hey,

Could you just add a conditional formatting rule to these cells and where they equal 0 then format as "--" ?

 

[Special-K99]

Custom formatting, not condtional formatting.

Excel shows "--"

Google Sheets shows all zeroes.

 

[fullspool]

Conditional formatting doesn't work either for my purposes, it works great in my template I shared but when I run my python script that creates new tabs based on the employees names who submitted a time sheet those values default to zero.
The accounting department wanted those entries to be -- or blank instead of showing "0" but it's beyond my capabilities.