Drain Cleaner or Drain Opener are not safe household products.
Liquid Fire Drain Opener or Drain Cleaner has the letter “d”.  These products actually cause damage to your house or home plumbing.  We’ve all seen a chrome drain trap with the bottom eaten away by drain cleaner.

Liqui-Fire is safe on water pipes plus it can also be used on drains, sewers, and septic pipes, septic tanks, and septic systems.

Liqui-Fire ( with no letter “d” ) looks like this and has endorsements here.

Damage to pipes from drain cleaners or drain openers can be seen here.

See the truth on drain cleaner here:
This could be your mother:
http://news.uk.msn.com/uk/articles.aspx?cp-documentid=154023713
This could be your grandmother:
http://news.sky.com/home/uk-news/article/15659011
Or is this your family pet?
http://veterinarianjoske.tumblr.com/post/2313770402/the-power-of-honey

You wouldn’t wash your face with drain cleaner and you don’t want drain cleaner in your pipes.

Thawing frozen pipes with drain cleaner or drain opener is not a good idea.  It may or may not work but the companies that market it will tell you it does.  Some of them lie just to get your money.

Drain cleaners or drain openers are extremely dangerous and continue to destructively eat anything including the pipes they were used in.  Do we really want to pay a plumber to replace sections of our pipes that drain cleaners and drain openers have destroyed?  That is costly.

Have you ever D.I.Y. and poured drain cleaner into your clogged sink only to find out that it ate through the plumbing beneath your sink and now you have a nasty mess below to clean up and possibly paint?  Many of us have.

Liqui-Fire is safe for thawing residential and commercial water intake pipes, drains, septic systems, septic tanks, septic fields, and sewage pipes or sewer lines.

It is always $19.99 plus tax.  To order, select your country here.