Two weeks without a clean is pretty good really. Most coils you can rinse under hot water, soak in pure grain alcohol (like vodka or everclear) or do a dry burn to clean them (some coils cannot be dry-burned because you will burn the filler or wicks) - or any combination of the above. You tube has thousands of videos about coil cleaning and general maintenance just type in your clearo name and search.
When I used clearos I found a quick hot water rinse every 2-4 refills and a dry burn every week kept them working very well. I could get more than a month out of most heads and even 6-7 weeks sometimes.
If you can't be bothered cleaning them, just pop in a new coil and away you go again.