Word size problems

Every time I want to have a specific word bigger then the others, I can't seem to go past the size of 24. For example:

[size=36]HI[/size]

Why is this and is there a way to fix it?

Hi,

Quick question: Do you have HTML activated? If so, try using this code:

Code:

[size=15]<[/size][size=15]font[/size][size=15] [/size][size=15]size=[/size][size=15]"6"[/size][size=15]>[/size][size=15]This is some text![/size][size=15]<[/size][size=15]/font[/size][size=15]>

If for some reason your HTML isn't activated, follow the next steps to achieve this:
1. Open your Admin Panel.
2. Click on the "General" tab.
3. Under the category: "Messages & E-mails" you'll find this option: Allow HTML []yes []no

Make sure you click yes and save it.

Regards,
Sir Chivas.