I did a service call today at a hair salon and found the breaker disconnect at the water heater was burnt up. The line side terminals and about three inches of the line side wiring to the breaker were toast. The owner needed hot water and it was too late in the day to get a new disconnect, so I bypassed the disconnect with 10-2 romex to get her hot water. The feed was romex and was being fed from a 200amp panel and 30a breaker about 50ft away. I will return tomorrow with new disconnect. My question is: After re-energizing the circuit, I Put an amp meter across each leg and it was pulling 33.9 amps. I checked the voltage and it was 239v. I then looked for a sticker on the water heater and found it had been torn away or fell off. I opened the access panels to the elements and found both elements were energized at the same time. The upper element was 3500w and the lower was too difficult to see. After about 20min. the amperage dropped to 19.2amps and then 10min. later dropped to zero. This water heater apeared to be about 40gal, just your typical house style water heater and about 5-7 yrs old. The owner said the water heater was a quick recovery type. I've never seen a water heater that both elements are energized at the same time and I'm concerned about the amp draw. Is this normal for a quick recovery water heater?? or is there something else with the t-stats going on??
Water Heater Elements
- Thread starter ote
- Start date
- Status
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Around here the POCO will not allow both elements on a residential to be energize. If the unit is designed that way then you obviously have the wrong wiring for it. I suggest you look closer and see if someone didn't replace the upper thermostat with the wrong one. The upper T-stat should be a spdt. I bet it is just a sp like the bottom one.
76nemo
Senior Member
- Location
- Ogdensburg, NY
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
That's quite normal. As far as your line side being toast, there's something alot larger at hand there
It is not normal for both elements to come on together-- not that I know about anyway. and 33.9 amps isn't normal on a 30 amp circuit.
76nemo
Senior Member
- Location
- Ogdensburg, NY
Sierrasparky
Senior Member
- Location
- USA
- Occupation
- Electrician ,contractor
I'd say that is why the breaker is toast
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I am confused- there are 3500 watt elements out there.
76nemo
Senior Member
- Location
- Ogdensburg, NY
The joke's on me,.........I need my other avatar, sorry.........DUH!!!!!!
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Try this....
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
I would say the factory wiring has been tampered with, the water heater was not keeping up, so some smarty has changed the internal wiring to allow both elements to be energized.
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
I usually just replace everything on a water heater call. Parts are cheap, labor to return and fix it again is not.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Mgraw
Senior Member
- Location
- Opelousas, Louisiana
- Occupation
- Electrician
There are simultaneous water heaters available. They operate just as the OP stated the one he was working on did. I would guess whoever installed it didn't bother to check the electrical requirements.
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
Water Heater Elements
Doing some calculations, if the top element was 3500w and the bottom (guessing here) was 4500w the the two added are 8000w. 8000w devided by 239v (actual reading) is 33.47amps. Pretty close to what I was reading with amprobe. When the upper turned off, I was reading 19.2amps, which is pretty close to the 18.82calculated amps. My next question is: How can I tell if this water heater was designed to run both elements at the same time or not without any nameplate?. I can change the circuit if I have to, just don't know how to tell if someone improperly re-wired t-stats or if WH was designed to run both at the same time?????
Doing some calculations, if the top element was 3500w and the bottom (guessing here) was 4500w the the two added are 8000w. 8000w devided by 239v (actual reading) is 33.47amps. Pretty close to what I was reading with amprobe. When the upper turned off, I was reading 19.2amps, which is pretty close to the 18.82calculated amps. My next question is: How can I tell if this water heater was designed to run both elements at the same time or not without any nameplate?. I can change the circuit if I have to, just don't know how to tell if someone improperly re-wired t-stats or if WH was designed to run both at the same time?????
Sierrasparky
Senior Member
- Location
- USA
- Occupation
- Electrician ,contractor
- Status