We needed to install Apache 2.4 on our RHEL 6 web servers due to the need for 'mod_ssl'. It appears as though when I ran the yum command to install 2.4 it didn't upgrading the existing 2.2 version, but rather installed 2.4 to run simultaneously with 2.2 (which I understand is due to the focus on providing stable apps instead of the newest versions).

The issue we're having is that to start Apache 2.4 we need to run 'service httpd24-httpd start'. Is there a way to configure 2.4 on RHEL6 so that running 'service httpd start' actually starts Apache 2.4 (we aren't using 2.2 at all).

I'm not the most advanced Linux user, so if I need to clarify anything in my problem description please let me know.

Thanks,
Tejama

Can you tell us what command you ran???
A bit confused here...since you're not using 2.2, why did you need to install 2.4 for the "mod_ssl"?? If you're using neither, then remove them both, and do a fresh install of the latest Apache.
You've been posting here for EIGHT YEARS now, about RHEL, and I find it hard to believe after all that time, you haven't learned anything. Also, since you're using RHEL6 that you are paying for (RIGHT???), have you contacted Red Hat support for help?

To install 2.4 I ran: (we have a local repo available with the RHSCL)

After reviewing my notes, the app team asked for 2.4. Forget the mod_ssl part, we are using it but the request to install mod_ssl and 2.4 came in at the same time and for some reason I remembered them as being connected. In the meantime, I just removed both 2.2 and 2.4, did a fresh install of 2.4 (with the yum command above). So I've got just the one version of Apache on the system now but to start the app I still have to run:

I'm just wondering if there's a way to change it so that 'service httpd start' starts Apache. When I run 'service httpd start' as the system stands now I get an 'unrecognized service' error message.

8 years ago I did have to setup a couple of RHEL 4 servers in the position I was in. Since that time I've been supporting all Windows servers and now I'm just getting back into RHEL (hence the gap in my posts from 2008 to 2015). In any case, we have RH support but the question just seems trivial when it really doesn't impact the functionality.

Ok...so again, have you contacted Red Hat for help??? If you're paying for an RHEL subscription, you are also paying for support and assistance. They could get you the right package, and I don't think that's it. That may be one that your team has put out on the local repository.
You'll have to find out where that package came from first. There may be an "httpd24-httpd" file in /etc/init.d...if so, try renaming it to httpd.
True, the question may be trivial, but you should use what you're paying for. RHEL support is there for you.