Show me in the code and I will believe you.
I just read it. I have the 2011 edition.
Now if it were in an equipment room it “maybe” different.
If you see this wire staple up a living room wall what would you think ?
Even if it was on the ceiling ?
I would think that there was nothing in the code that I could cite as long as it followed the building surface. Perhaps ugly, but compliant. Again, the physical damage assessment is entirely subjective.
I read the where necessary…:roll:
It would not be allowed as the NM cannot be used outside, nor can raceways support other raceways or cables.
(B) Types NM and NMS. Types NM and NMS cables
shall not be used under the following conditions or in the
following locations:
(1) Where exposed to corrosive fumes or vapors
(2) Where embedded in masonry, concrete, adobe, fill, or
plaster
(3) In a shallow chase in masonry, concrete, or adobe and
covered with plaster, adobe, or similar finish
(4) In wet or damp locations
(B) Raceways Used as Means of Support. Raceways
shall be used only as a means of support for other raceways,
cables, or nonelectrical equipment under any of the
following conditions:
(1) Where the raceway or means of support is identified for
the purpose
(2) Where the raceway contains power supply conductors
for electrically controlled equipment and is used to support
Class 2 circuit conductors or cables that are solely
for the purpose of connection to the equipment control
circuits
(3) Where the raceway is used to support boxes or conduit
bodies in accordance with 314.23 or to support luminaires
in accordance with 410.36(E)
I’m done !
So because you don’t agree you are just going to leave instead of hearing and learning other opinions? 
Thanks Jim. We learned something here. 
Yes! Exactly !
First I heard the timer was 110 then I can staple romex up a wall unprotected.
Opinions are what they are worth. Nothing!
I want facts not conjecture. If not I’m wasting my time.
In a world of infinite possibilities . I try to limit the possibilities of the wire being damage by properly protected it as best I can.
The rest is all bulls h i t IMHO.
You were given direct NEC code cites that allow those installations. I don’t know how much more factual you want.
You were also shown that there are 240 volt rated units designed for that purpose.
Unfortunate that directly above was a suspended combined conditioning/heating unit which is a typical install in Florida because if the severe heat in attic
During a hurricane the unit fell, improper supports, gouged the supply wire while the timer was in the off cycle. During the eye of the hurricane while things we’re calm, the owner was inspecting the load crash in the garage which was covered in water… The timer came on
While I value you opinions on a variety of posts, it is obvious you don’t perform home inspections. The top of the water heater will eventually be covered with kids balls, sporting goods, plastic bags, empty wine bottles, trash, Christmas wrapping, tools, empty mason jars, canned goods, laundry detergent bottles, bleach bottles, bags of clothing for the Goodwill… and it goes on and on. That wiring needs to be protected from everyday homeowner activities. Code, schmode. This is real life. 
I agree. Add two NM straps and you’re good to go. Add one on the metal clad cable within 12" of the timer too.
I agree with Jim Port nothing wrong with the unprotected wiring and I am not a CMI. I have only installed about twenty million of those timers they make so many different types for different services look in a Grainger and learn something.
Those timer motors can be 240 volts or 120 volts depending on the application and what they are used for they can have normally open points normally closed points or a combination of both open and closed. On a water heater the motor would most likely be 240 volts and one leg of the 240 volts thru a normally closed set of points that opens for a length of time designated by the arraignments of the pins located on the wheel. They also have a manual lever for bypassing the pins on the wheel.
In my world of refrigeration they are used for defrost timers on low temp applications
Well ! I know my area requires it. And most of my state.
Why leave a 240 wire unprotected. Why to save $3-5 ?
I will continue to have my electricians wire them in conduit. It just makes a better job.
Same in Central Florida, they won’t pass an exposed cable on a water heater. The OP is in South Florida, I’m sure it’s the same down there.
Dom.
Agreed to be secured and move on. However in Ontario it is best to be covered with a 7/16 inch flexible conduit.
Rule 12-518 where there is a chance it is exposed to mechanical injury. I would not want to make that call on the location in this picture.
The liquid tight or flex conduits that were suggested are not on the list of materials to be used against physical protection.
Where did this list come from?
Jim, I am not sure about flex, but what about power whips for outdoor a/c condenser units – those are enclosed in liquidtight, and that application clearly calls for physical protection.