Master Plumber Hot Water Heater Timer Model #440016

I found installation instructions for this electric hot water heater time(energy saver) but no operational instructions. i.e. the thing is set aready and turns on fans in rooms i don't use, shuts off my hot water when i don't want it to. what i'm looking for is the way to actually USE the timer to set it the way i need it for my home. note, was installed in a foreclosed home. great item but useless and frustrating at this point.
Any help out there?
a manual would be great. the DIY network was somewhat helpful but found the post on this site. thanks

Unless you have extended time away from the house, a timer on the electric WH doesn't do much. The insulation on an electric WH is normally pretty decent, and you may not be saving much of anything, and when the water cools off, can start to grow stuff you don't want.

If the timer affects anything other than the WH, it is wired wrong, and you may have a dangerous situation there that must be corrected. Impossible to say what's going on without being there to investigate.

It sounds like a "load controller" which monitors the electrical usage in the house and turns off items when that load exceeds a previously set limit. Typically, the shedding order is like this. First the dryer's heating elements, then the water heater, MAYBE the oven's elements, and finally the air conditioners. There are several ways to eliminate all or part of the operation. Either by turning off the circuit breaker controlling it, or increasing the usage limitation.

It sounds like it may be connected to more than just the water heater, and there is other things connected to its output.

This may help, It is the operating instructions;

http://www.intermatic.com/~/media/files/intermatic/products/instructions/timers/wh40 - english.ashx

I hope this helps you.

Have a great day.

DonL

Unless you have load priced electric, a timer often is more of an annoyance than a help. ANd then, if you do have load based pricing, the thing normally comes with some control from the power company.

jadnashua said:

Unless you have extended time away from the house, a timer on the electric WH doesn't do much. The insulation on an electric WH is normally pretty decent, and you may not be saving much of anything, and when the water cools off, can start to grow stuff you don't want.

If the timer affects anything other than the WH, it is wired wrong, and you may have a dangerous situation there that must be corrected. Impossible to say what's going on without being there to investigate.

Click to expand...

I agree. Electrics already have fairly low ambient loss rates compared to gas (immersion coils and no heat transfer flue down the center...plus the bottom end of an electric is insulated.) The tank isn't likely to cool down much during the day. (And note that while electric resistance heating efficiency is very high, the generation of electricity is much less thermally efficient than the burner, vent, and heat transfer system of a gas water heater.)

The really critical concern with electric tank heaters is that if they are set in the recommended 120-125 F energy saving range even a few degrees of cooling (or leaving the heater off all day after a shower...then having it kick on at night) results in a temperature that is conducive to the growth of legionella bacteria. And when it warms back up to 120 F the bacteria isn't killed, it just goes dormant...takes a lot higher temp to kill it.

In the studies I've seen online of legionella, they noted that electric water heaters were much more susceptible to the problem in the samples they took. I can come up with a number of engineering reasons that this would be expected (e.g. longer recovery times, greater stratification, etc.)

The reason folks might be tempted to use a timer is if they have on peak/off peak metering. They can save money (but very little energy) by doing the heat cycles off peak. Unfortunately, that creates the potential for the unintended consequences mentioned above. Which leads me to wonder if it would be wise to run the water heater at much higher temps to compensate...a Catch 22.