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dan orourke
07-16-2007, 06:58 PM
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Trent Tarter
07-16-2007, 08:02 PM
1- Yes it is OK for the water heater to be connected to the timer.

2-As for the cable not being installed in conduit. I usually recommend installing in flexible conduit, however if it's in a secure closet and is unlikely to become damaged I usually do not report it.

3-Steel pipe or Galvanized, Dan I have never separated the two it is called Galvanized steel.

4-This is an electric water heater. The lower and upper elements are inside of the water heater surrounded by water, therefore they can not ignite vapors.

wayne soper
07-16-2007, 08:08 PM
DAN, you know those magnetic doodads on all the refrigerators of the homes you inspect. They are there just for you to check the water lines.

Jerry Peck
07-16-2007, 08:35 PM
1- Electrical cable for water heater is connected to a timer.....surely this wrong???

That is correct, that is wrong. Trent missed, or left out, one key word - "cable" (as shown in the photo). That is not allowed to be run exposed like that.


2- Is it required for the electrical cable to be in a flex conduit?

Or rigid, or EMT, or IMC, or some approved raceway which is rated to provide protection from physical damage.


3- Do you think steel or galvanized piping is used on water supply. I always find it hard to tell the difference.

Both are shown, what was up above those flexible copper connectors?


4- Water heater is in a closet in the garage. Should it be elevated? I was thinking the lower element could ignite vapors?????

Yes. If the closet floor is elevated, then the ignition source may already be 'elevated' enough.

Also, those flexible copper connectors reduce the size of the pipe, thus they reduce the opening size of the T&P relief valve, thus they are not allowed to be used for T&P relief valve discharge lines.

Bob Mayer
07-16-2007, 09:53 PM
1- Electrical cable for water heater is connected to a timer.....surely this wrong???

Jerry is right about the NM cable being wrong, of course.

If the house has time-of-day electric metering the timer will turn the heater off during peak-pricing times. I know of one area near here that has 1/4 the kWhr price from 8 pm to 10 am.

Rick Hurst
07-16-2007, 10:09 PM
4-This is an electric water heater. The lower and upper elements are inside of the water heater surrounded by water, therefore they can not ignite vapors.

Whoops!

brian schmitt
07-17-2007, 08:30 AM
the wire connected to the thermostat for the lower element is not immersed in water and is located on the outside of the tank usually within 18" of the floor.this could arc and spark quite easily so elevation is required. if the closet had an exterior door with weatherstripping that would prevent fumes from entering the enclosure elevation may be waived.

Jerry Peck
07-17-2007, 09:29 AM
4-This is an electric water heater. The lower and upper elements are inside of the water heater surrounded by water, therefore they can not ignite vapors.


Whoops!

Oops - I missed that "not" part of "can not".

Trent, bottom elements CAN ignite vapors. Have you never seen arced and burned up terminals at the lower element? How about the bottom thermostat switching on and off - never seen a burned up thermostat either? (Just the thermostat switching on and off can create the spark needed to ignite vapors when the vapors are that the proper fuel/air concentration, above the LFL and below the UFL.)

Jerry Peck
07-17-2007, 11:14 AM
Jerry,

"flex connectors"

Are you refering to the water supply line? That is okay , is it not?

Depends, I was referring to both the supply and T&P ones.

They are okay on the supply, but, for those, I was referring to the question of whether or not the piping was galvanized or copper.


The TPR I agree is not okay....however, I battle a loosing battle with builders on that one- they say it does not reduce the size.....any documentation on it?

From the IRC.
- P2803.6.1 Requirements for discharge pipe.

- - The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve shall:
- - - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.



This does not specify 'nominal trade size', it says "Not be smaller than the diameter of the outlet of the valve". Those flexible copper ones have an interior diameter which is "smaller than the diameter of the outlet of the valve". Next time you are in one of the Big Box stores, measure the ID of a copper flexible connector and the ID of on valve.

Trent Tarter
07-17-2007, 09:45 PM
I was not aware that standard building practices require an 18" height for all types of water heaters installed in garages. But it appears that they do.

Jack Feldmann
07-18-2007, 06:56 AM
Jerry,
Where would you measure the diameter of the TPR valve?

If you measure the inside of the female threads at the discharge point, as soon as you install a threaded pipe or fitting you have reduced the diameter, if only the thickness of the pipe itself (approx 1/8" for steel pipe), even if you use 3/4" pipe.

I always thought it was nominal pipe size that mattered, not an actual measurement. Maybe I have been wrong all these years - it wouldn't be the first time.
JF

The TPR valve has a 3/4" female thread fitting. If you screw in a section of 3/4" steel pipe, or a 3/4"female copper fitting to solder a 3/4" pipe for the extension, you have, by your definition "reduced" the size, just from the wall thickness of the fitting. However, because 3/4" steel or copper pipe was used, I can't imagine a AHJ turning it down.

Maybe I'm just not following your explanation or logic.

brian schmitt
07-18-2007, 08:25 AM
the u.p.c. is more clear sec 608.5. ... will not reduce the internal bore of the pipe or tubing(straight lengths as opposed to COILS)

Jerry Peck
07-18-2007, 03:14 PM
Jerry,
Where would you measure the diameter of the TPR valve?

If you measure the inside of the female threads at the discharge point, as soon as you install a threaded pipe or fitting you have reduced the diameter, if only the thickness of the pipe itself (approx 1/8" for steel pipe), even if you use 3/4" pipe.

Jack,

Measure the ID of a 3/4 pipe (that's what I should have said instead of referring to the valve opening itself) ... then measure the ID of one of those flexible connectors. They are smaller.

Down in South Florida where I used to be, those were not allowed because 'they were too small' internally.

Jack Feldmann
07-18-2007, 03:56 PM
I get it with the flex. I thought you were talking about pipe size reduction in general.
JF