Rich Greenberg wrote:
In article ,
Bill Christens-Barry wrote:
We have a high efficiency Rheem EverClean gas hot water heater (early
model, around 8 - 10 years old) that has developed a perplexing problem:
from time to time, the pilot light will go out, and I have trouble
relighting it.

Two potential causes come to mind:
1: the gas orifice is dirty;
2: the sensor bulb next to the pilot flame isn't getting hot or
actuating for some reason.

From your description, my first guess would be the thermocouple. They
are available at the borg or a plumbing supply place. Remove the old
one (don't lose the mounting screw(s)/hardware) and bring it in for a
match. What looks like a small copper tubing is really an electrical
connection, a coaxial cable.

What Rich says,

and don't screw around poking things in the orifices or you will damage
them.

--
Rich Greenberg Marietta, GA, USA richgr atsign panix.com + 1 770 321 6507
Eastern time. N6LRT I speak for myself & my dogs only. VM'er since CP-67
Canines:Val, Red & Shasta (RIP),Red, husky Owner:Chinook-L
Atlanta Siberian Husky Rescue. www.panix.com/~richgr/ Asst Owner:Sibernet-L