Merging Multiple Columns Into a Single Column

I have multiple columns of data that I need to merge into one column. These data is composed of water flows from pumps that were recorded at different times.

PUMP1
Column A
Time
12:00
12:32
12:47
12:54
etc

PUMP1
Column B
Flow
32
23
31
33
etc

PUMP 2
Column C
Time
12:03
12:32
12:40
12:54
etc

PUMP2
Column D
Flow
43
42
46
44
etc

As you can see, the time the readings were taken could be the same or different. I would like to combine Columns A and C into one column that combines all the times that readings were taken but delete duplicate times. I would basically like to create a Column E that looks like Column E, below. Then I will use a Vlookup to match pump flows to the times in Column E. There are around 35,000 entries, so I can't do this manually.

Column E
12:00
12:03
12:32
12:40
12:47
12:54

Any help would be greatly appreciated!

Originally Posted by AZ-XL

All you datas starts after third row

for time
=IFERROR(IFERROR(SMALL(IF(ISERROR(MATCH($A$3:$A$6,$E$1:E1,0)),$A$3:$A$6,""),1),
SMALL(IF(ISERROR(MATCH($C$3:$C$6,$E$1:E1,0)),$C$3:$C$6,""),1)),"") CSE

for flow
=IFERROR(IFERROR(SMALL(IF(ISERROR(MATCH($B$3:$B$6,$F$1:F1,0)),$B$3:$B$6,""),1),
SMALL(IF(ISERROR(MATCH($D$3:$D$6,$F$1:F1,0)),$D$3:$D$6,""),1)),"")

Simulated in file

Thank you! Your code is definitely pretty impressive! I am trying to apply it to my data and it is not working. If I cut and paste your formula and apply it to your excel file you attached, it does not seem to be working either. What am I missing?

This can be done by a code. How comfortable are you with using a code?

Originally Posted by AZ-XL

Maybe you do not hit Ctrl+Shift+Enter keys at the same time. Formulas above are array formulas, thus after formula press C+S+E, not only enter

That was it, it appears to work now! I just had to hit Ctrl+Shift+Enter;I just didn't know array formulas needed the CSE. Thank you so much

Originally Posted by AB33

This can be done by a code. How comfortable are you with using a code?

Although, AX-XL solution worked. I would be interested to know know a code solution would work. Unfortunately I haven't worked with any excel code since college, so I am a bit rusty.

If AX-XL solution worked, no need for complication. Avoid a VBA if you can is the motto of the day.

Originally Posted by AB33

If AX-XL solution worked, no need for complication. Avoid a VBA if you can is the motto of the day.

It worked great in my test. Then I applied it to the whole range of data ~37,000 rows and the calculation time has gone through the roof. It takes approximately 7 min to calculation 500 rows...

Well, I think I just figured out a simple and quick way to do this. Excel 2007 apparently has a "remove duplicates" button in Data/Data Tools. It appears I can just copy Column A under the last entry in Column C and then hit the remove duplicates button for Column C. Then I can sort the column with the "A to Z" sort button and bingo. Excel performs the duplicate button function for the 37,000 rows in less than a second. The sort button goes even faster.

While AX-XL is spiffy and definitely works, it would take hours to perform the array function on my computer with large amount of data involved.