# Can I replace 4000w water heater element with 3800w?



## TitaniumVT (Nov 27, 2009)

Nobody? Ok, well after doing some more research on the web, I think I know the answer:

1. The preferred (STRONGLY RECOMMENDED) option is to replace the element with another one of identical voltage and wattage (in my case 4000 watts)

2. You should never replace the element with a higher rated one (e.g., 5000, 4500, etc.) The circuit breaker and wiring may not be capable of handling the higher current draw and could start a fire.

3. You could theoretically replace the element with a lower rated one (e.g., 3800 in my case), but the main drawback is that it will reduce the recovery rate of your water heater (i.e., take longer to heat the water back up). 

So I'm going to check a plumbing supply store tomorrow for a 4000 watt element. If I'm not able to find one, I'll pick up the 3800 watt model since it's lower rated but really close to the original spec.

Hope this info will be useful to someone down the line. A few more precautions when replacing the water heater element:

- TURN OFF POWER TO THE WATER HEATER BEFORE DOING ANY WORK ON IT. It's running at 220 or 240 volts which poses a serious electrocution risk. Don't touch the wires without confirming the power is off

- After changing the elements, REFILL THE TANK COMPLETELY AND GET AIR OUT OF THE SYSTEM before turning the power back on. The elements are intended to operate in water. If they're not immersed in water when you turn them on, they can burn out (dry fry) in a few seconds...at which point, you'll be heading back to the store to get a new element.


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## rjniles (Feb 5, 2007)

Why are you replacing an element without knowing what is really wrong?

Test the element and the upper t-stat with a multimeter. With the power on connect a voltmeter across the terminals of the upper element- you should read 240 volts. If you get no reading rotate the dial on the t-stat from high to low setting to see if you get power. If still no voltage, test for voltage at the input terminals of the t-stat. These tests will tell you whether the t-stat is working.

With the power off, disconnect one wire to the upper element, Connect an ohmmeter across the element. You should get a reading of 12 to 15 ohms.

Repeat tests on lower element and t-stat. Understand the lower t-stat only gets power when the upper t-stat is satisfied and switches the power down to the lower.


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## TitaniumVT (Nov 27, 2009)

Thanks RJ. I'll test it with a multimeter, but everything I've read says the power should be off, and that you should test it by putting one clip on a terminal, and the other on the metal water heater case. I don't feel comfortable testing the power with 240 volts going through the heater.

I'm inclined to just replace them because they're cheap (less than $60 to replace both elements and both thermostats) and they're older (so it should save me hassle later.


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## DangerMouse (Jul 17, 2008)

How old is "old"? It may be wiser to just replace the unit?

DM


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## TitaniumVT (Nov 27, 2009)

It's probably 15 years old. It's not leaking at all, so I'm resistant to throwing it into a landfill. Turned out that spending $26 on two new elements today fixed it! Way cheaper and way more environmentally responsible than getting a new one. 

Electric water heaters are mechanically vey simple, and tend to have a longer service life than gas powered heaters. About the only things that could wrong with them are bad thermostats, bad heating elements, and a rusted through tank. The first two are $30 fixes each. The last one merits getting a new water heater.

I would be happy to get another 5 years out of this one. If it's less, so be it. I'll replace it when it starts to leak.


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## Know It ALL (Nov 13, 2010)

Glad to hear your water heater is back up running.
TIP: Once a year. Turn off power or (gas in my case). Allow water temp to cool. Connect a garden hose to the base spigot. Close incoming water valve. Open bottom drain and high pressure blow off valve to get some air inside. Once the tank has drained, close blow off and open incoming water 100%. I place my garden hose in the bath tub so I can see what is being flushed out. Do this twice. Make sure the blow off and bottom spigot does not leak when you put the unit back in service.
My old state unit is over 14 years old.


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