House was built in 2005, hot water heater wiring goes into the sprinkler timer control box, is that okay?
That’s a timer to control the water heater, and it can be used for that purpose; the wiring from the timer to the appliance isn’t installed properly.
Dom.
Looks like a homeowner rearranged some things… My biggest concern would be that the timer is rated for the wattage that the water heater draws (4500 watts) cable is properly rated and box is grounded properly… 240v is not something you want to second guess. If you can’t answer the question, ask a qualified electrician who can.
“sprinkler timer control box” That is funny !
You can flip up the plastic in front of the wiring to see if it is 220V ?
Sprinkler timers look nothing like that .
Its not for a sprinkler, it a timer for an electric device (outside lighting, pool pump, etc…), as stated earlier, it may not be rated for the demands of a water heater, plus its wired wrong. Just write that and move on.
Mike, what is wired wrong? I can’t even see inside the timer. What am I missing here? 
If you look it has two connections for “LOAD” and two for “LINE” wouldn’t that indicate to you it would be 220?
Exposed wiring , need to be in conduit.
Of what I can see: Is the unprotected Romex (NM-B) a proper way to supply power to this thing? Shouldn’t it be wired via a Liquidtite or an FMC whip?
A little knowledge is a dangerous thing…
And you point being ?
I’ve wire many of these.
Most say water heater time on the front cover.
The service to the water heater should be in conduit, the ground appears to be dubious although you can’t completely see it, there is one ground on the ground screw but the other isn’t connected there, suspicious. I’d love to see the photo with the insulator flap up. Typically water heaters are 220 (although I cant tell) that style timer appears to be rated for 110.
Look at the attachment and tell me how you figure it is for 110v.
It has two lines and two loads.
Unless I’ve overlooked something . I’m darn sure no expert.
The electric code does not require the feed to the WH to be in liquidtite or conduit. The only issue with the NM that I see is that it is not properly secured. Securing it properly would allow it to closely follow the surface which is a compliant method.
BTW, it is 240, not 220.
http://ecx.images-amazon.com/images/I/81X%2B6BHmK7S.SX425.jpg
Intermatic WH40 Electric Water Heater Timer, Grey
334.15(B) Protection from Physical Damage. Cable shall be
protected from physical damage where necessary by rigid
metal conduit, intermediate metal conduit, electrical metallic
tubing, Schedule 80 PVC conduit, Type RTRC marked
with the suffix -XW, or other approved means. Where passing
through a floor, the cable shall be enclosed in rigid
metal conduit, intermediate metal conduit, electrical metallic
tubing, Schedule 80 PVC conduit, Type RTRC marked
with the suffix -XW, or other approved means extending at
least 150 mm (6 in.) above the floor.
Type NMC cable installed in shallow chases or grooves
in masonry, concrete, or adobe shall be protected in accordance
with the requirements in 300.4(F) and covered with
plaster, adobe, or similar finish.
I’m with Jim, there is nothing wrong with the wiring.
Physical damage is not a defined term in the NEC and is an individual determination. What damage do you see happening to the cable?
(A) Type NM. Type NM cable shall be permitted as follows:
(1) For both exposed and concealed work in normally dry
locations except as prohibited in 334.10(3)
(2) To be installed or fished in air voids in masonry block
or tile walls
(B) Type NMC. Type
334.15 Exposed Work. In exposed work, except as provided
in 300.11(A), cable shall be installed as specified in
334.15(A) through ©.
(A) To Follow Surface. Cable shall closely follow the surface
of the building finish or of running boards.
;-)...