Instruction: Given a question and the related document, predict if the question is answerable based on the information provided in the document. Output only yes or no.

Input:
Question: Does this unit have to be connected to electricity ? If yes, what's the voltage 110 or 220
Document: i have had the unit for a couple for months now. i would like to say that it works great and i would recomend it to anyone with an iron problem. when i first got it, it didnt come with the instructions.... i contacted the vendor and they sent me a link to downlaod the files i needed.its a great filter
We purchased this unit in February 2014 to eliminate a hydrogen sulphide (rotten egg) smell and this unit did the trick. I installed the unit myself and if you have basic plumbing skills, you should have no problem. Just note this unit expels a significant amount of water during the backwash cycle. So, be sure you have a drain plan (the drain uses a 1/2" inside diameter drain hose).
We have well water and an iron filter is a necessary item for us. We had a different one for several years and it was time for an upgrade. This one is great for the replacement. Easy to install, but if you do have questions they are very helpful.
Answer: no