Electric Question about Water Heater

[cleddy]

My 50 gallon Electric water heater in a un inhabitated farm house blew a 25 amp fuse and went cold. I replace the fuse with 30 amp fuse and turned it back on and everything seemed to be heating fine after a few hours. before leaving for the day I looked at the fuse box and noticed it was WARM to touch. The wires were not warm but the whole Fuse box was. Copper blades inside are clean and appear to be okay. Should I be concerned it could start a fire and BURN the house down?? Switch is off for the Moment, Cleddy

 

[1948CaseVAI]

My 50 gallon Electric water heater in a un inhabitated farm house blew a 25 amp fuse and went cold. I replace the fuse with 30 amp fuse and turned it back on and everything seemed to be heating fine after a few hours. before leaving for the day I looked at the fuse box and noticed it was WARM to touch. The wires were not warm but the whole Fuse box was. Copper blades inside are clean and appear to be okay. Should I be concerned it could start a fire and BURN the house down?? Switch is off for the Moment, Cleddy

Uhhhh yes. Upping the capacity of the breaker is NOT the way to repair a blown breaker. Fix the problem causing the added draw.

 

[buickanddeere]

Did you measure how much current is flowing on each live line ? Is there any current flowing in the water pipes or the ground wire ?

 

[jhwis]

My 50 gallon Electric water heater in a un inhabitated farm house blew a 25 amp fuse and went cold. I replace the fuse with 30 amp fuse and turned it back on and everything seemed to be heating fine after a few hours. before leaving for the day I looked at the fuse box and noticed it was WARM to touch. The wires were not warm but the whole Fuse box was. Copper blades inside are clean and appear to be okay. Should I be concerned it could start a fire and BURN the house down?? Switch is off for the Moment, Cleddy

Are both elements working? To be fair, 25 seems low for amperage, but that depends on the size wire you have. Has this been functioning like this for a long time?

 

[Janicholson]

My 50 gallon Electric water heater in a un inhabitated farm house blew a 25 amp fuse and went cold. I replace the fuse with 30 amp fuse and turned it back on and everything seemed to be heating fine after a few hours. before leaving for the day I looked at the fuse box and noticed it was WARM to touch. The wires were not warm but the whole Fuse box was. Copper blades inside are clean and appear to be okay. Should I be concerned it could start a fire and BURN the house down?? Switch is off for the Moment, Cleddy

one source example.A warm fuse box needs to be replaced with a new circuit breaker based panel. (putting in a larger fuse is just not a solution that is safe. If there are no people there, the load should be only the furnace and the water heater. Thus for safety and security spend the bucks to upgrade the Fuse panel to modern standards. Water Heaters are almost all 240volt single phase with 2 breakers, that are tied together so they trip together. cartridge fuses are independent from each other and can leave the circuit hot to ground at the device if only one fuse blows. Jim

 

[Dave G9N]

A warm fuse box needs to be replaced with a new circuit breaker based panel.

Oh yeah, get that old thing out of there ASAP.

The contacts in the box may be oxidized, causing enough contact resistance in the old service entrance panel to warm the box. If that has started happening, the heat will cause the contacts to oxidize faster and heat even more until they get hot enough to do some damage.

I bought a 30 year old house in 1984 with a 60 amp service entrance panel with paper fuses for the main. Electric hot water, range and clothes dryer, totaling over 90 amps, but the range and dryer shared the same wall outlet and couldn't both be plugged in at the same time.

The contacts in the main shutoff switch were corroded and were heating up the box. The contacts in the panel got hot enough to melt the solder joints in the main fuses, but the current was not high enough to blow the fuses. I thought the fuses were blowing at first, but the paper wasn't discolored, which wasn't adding up. I cut them open and found that the wire that was designed to melt was intact, but no longer soldered to the ends. Then I looked around inside. It was black around the switch. I had a better look at the burned up contacts after it was removed, and can't see how it didn't catch fire.

Edit, I reread the description and the clean blades do argue against my hypothesis, but they are not the only contacts. I would have it looked at soon.

 

[cleddy]

Oh yeah, get that old thing out of there ASAP.

The contacts in the box may be oxidized, causing enough contact resistance in the old service entrance panel to warm the box. If that has started happening, the heat will cause the contacts to oxidize faster and heat even more until they get hot enough to do some damage.

I bought a 30 year old house in 1984 with a 60 amp service entrance panel with paper fuses for the main. Electric hot water, range and clothes dryer, totaling over 90 amps, but the range and dryer shared the same wall outlet and couldn't both be plugged in at the same time.

The contacts in the main shutoff switch were corroded and were heating up the box. The contacts in the panel got hot enough to melt the solder joints in the main fuses, but the current was not high enough to blow the fuses. I thought the fuses were blowing at first, but the paper wasn't discolored, which wasn't adding up. I cut them open and found that the wire that was designed to melt was intact, but no longer soldered to the ends. Then I looked around inside. It was black around the switch. I had a better look at the burned up contacts after it was removed, and can't see how it didn't catch fire.

Edit, I reread the description and the clean blades do argue against my hypothesis, but they are not the only contacts. I would have it looked at soon.

I am wondering about that also. Maybe the Pivots points are bad. About a year ago a different fuse box burn off one of the knife contacts. Also seemed to be a P****y smell in room above heater and basement when heater was trying to get back up to hot?? I am suspecting something with the water heater also now???

 

[cleddy]

My 50 gallon Electric water heater in a un inhabitated farm house blew a 25 amp fuse and went cold. I replace the fuse with 30 amp fuse and turned it back on and everything seemed to be heating fine after a few hours. before leaving for the day I looked at the fuse box and noticed it was WARM to touch. The wires were not warm but the whole Fuse box was. Copper blades inside are clean and appear to be okay. Should I be concerned it could start a fire and BURN the house down?? Switch is off for the Moment, Cleddy

After the heater was trying to get back up to hot I noticed a P****y smell in room above heater and in the basement. I was wondering if a animal got in the crawl space or something but there is no way, The wires going to heater did not seem to be warm. I suspecting water heater now after all the replys??? I had some trouble about a year ago and replaced fuse box when it burned a contact off????

 

[Janicholson]

If you shut off the power to the heater, then disconnect the electricity from the heater elements (keeping the wires organized) you should be able to check as follows (an ohm meter is needed) Using RX1 setting, put the two meter leads together it should read near zero. touch the black lead to the water tank steel and the red lead to one of the two terminal screws. The meter reading should not change from when not touching the screw. Do the same for the other screw. Any reading is a ground fault indicating the element has burned through the cladding, or corroded through so the electricity can find a path to the water. Bad element, replace it. Do the same for the other element, making the same decision. If there is no change in the meter on either element, at least they aren't ground faulting.
Next use the meter to check the elements for conductivity. this is done by placing the black lead on one terminal screw, and the red one on the other screw. There should be between 8 and 12 ohms displayed on the meter. If much more than that, or no reading, the element is open and bad.
I am also going to repeat that if your "Fuse Box" has actual fuses in it, it needs to be replaced as I indicated earlier. This is not really an option. If any component of a circuit box gets hot, the device is suspect. Now that all of us have understood some of the circumstances, it needs attention. Jim

 

[Roger in Iowa]

If un-inhabited why do you have the water heater even operating?

 

[Hemmjo]

My 50 gallon Electric water heater in a un inhabitated farm house blew a 25 amp fuse and went cold. I replace the fuse with 30 amp fuse and turned it back on and everything seemed to be heating fine after a few hours. before leaving for the day I looked at the fuse box and noticed it was WARM to touch. The wires were not warm but the whole Fuse box was. Copper blades inside are clean and appear to be okay. Should I be concerned it could start a fire and BURN the house down?? Switch is off for the Moment, Cleddy

There are lots of old fuse boxes still in use. The problem may be your box. It also may NOT be the problem.

To me , a warm box and cool wires do not indicate over current. Heat is generated by resistance. Heat also lowers current. I suspect you have corroded connections in that box. Not just the fuse contacts. Loose screws also increase resistance, therefore heat. As mention in a previous post, heat can damage a fuse.

In reality fuses always fail due to heat. You can tell a lot by examining the fuse element. If it looks like “exploded” it was caused by a sudden large over current. It it just looks melted it was caused by small over current for an extended time OR bad connection transferring heat into the fuse.

Check all of your connections in the box. Check the elements in your tank. You may find the problem is the tank after replace the box.

Let us know what you find.

 

[cleddy]

Are both elements working? To be fair, 25 seems low for amperage, but that depends on the size wire you have. Has this been functioning like this for a long time?

I [think it actually suspose to be 30 amp fuses. but wire is 12-2 copper running short distance from 40 amp breaker box. Been wired this way since 1960 with no problems until now??

 

[cleddy]

If you shut off the power to the heater, then disconnect the electricity from the heater elements (keeping the wires organized) you should be able to check as follows (an ohm meter is needed) Using RX1 setting, put the two meter leads together it should read near zero. touch the black lead to the water tank steel and the red lead to one of the two terminal screws. The meter reading should not change from when not touching the screw. Do the same for the other screw. Any reading is a ground fault indicating the element has burned through the cladding, or corroded through so the electricity can find a path to the water. Bad element, replace it. Do the same for the other element, making the same decision. If there is no change in the meter on either element, at least they aren't ground faulting.
Next use the meter to check the elements for conductivity. this is done by placing the black lead on one terminal screw, and the red one on the other screw. There should be between 8 and 12 ohms displayed on the meter. If much more than that, or no reading, the element is open and bad.
I am also going to repeat that if your "Fuse Box" has actual fuses in it, it needs to be replaced as I indicated earlier. This is not really an option. If any component of a circuit box gets hot, the device is suspect. Now that all of us have understood some of the circumstances, it needs attention. Jim

Thats what I am going to do-check everything. One side of the fuse box gets really hot after a short time on. Too hot to touch?? New brealer boxes are cheap and easy find?

 

[cleddy]

If un-inhabited why do you have the water heater even operating?

Its my Man cave in the country. Nice to was up & use bathroom when working on my tractors and farm stuff.

 

[Hemmjo]

I [think it actually suspose to be 30 amp fuses. but wire is 12-2 copper running short distance from 40 amp breaker box. Been wired this way since 1960 with no problems until now?

I am wondering about that also. Maybe the Pivots points are bad. About a year ago a different fuse box burn off one of the knife contacts. Also seemed to be a P****y smell in room above heater and basement when heater was trying to get back up to hot?? I am suspecting something with the water heater also now???

12 gauge wire is only rated for 20amps.

Are you saying there is a 40amp circuit breaker feeding the old fuse box through #12 conductors? Does the 40A breaker feed any thing else? Is there room in the box for another breaker?

We do not have nearly enough information regarding this situation to make proper recommendations.

 

[buickanddeere]

My 50 gallon Electric water heater in a un inhabitated farm house blew a 25 amp fuse and went cold. I replace the fuse with 30 amp fuse and turned it back on and everything seemed to be heating fine after a few hours. before leaving for the day I looked at the fuse box and noticed it was WARM to touch. The wires were not warm but the whole Fuse box was. Copper blades inside are clean and appear to be okay. Should I be concerned it could start a fire and BURN the house down?? Switch is off for the Moment, Cleddy

Dual element tank style heaters are factory setup to operate only one heating element at a time .

Top element first and after the top of the tank is up to temperature . Then the thermostat opens the circuit to the top element . And energizes the lower element .

Elements are usually 4800W however 3500W and 5300W heating elements do exist . They should draw approx 20, 14.5 and 22 amp.

 

[cleddy]

12 gauge wire is only rated for 20amps.

Are you saying there is a 40amp circuit breaker feeding the old fuse box through #12 conductors? Does the 40A breaker feed any thing else? Is there room in the box for another breaker?

We do not have nearly enough information regarding this situation to make proper recommendations.

I am sorry for the confusion. The 40 amp breaker also feeds the dryer plug. The whole breaker panel has several breakers-60 amp for range, 40 amp for water heater& Dryer, 20 amp for 240 v water pump,30 amp for 240 v window air conditioner, and several 15 & 20 amp for all the wall plugs& lights. The house is very old and Grandparents got Rural Electricity in 1950's and a lot of stuff is not up to code for this day N Age??The only things having good size wire is the Range & Air Conditioner Plugs?

 

[cleddy]

There are lots of old fuse boxes still in use. The problem may be your box. It also may NOT be the problem.

To me , a warm box and cool wires do not indicate over current. Heat is generated by resistance. Heat also lowers current. I suspect you have corroded connections in that box. Not just the fuse contacts. Loose screws also increase resistance, therefore heat. As mention in a previous post, heat can damage a fuse.

In reality fuses always fail due to heat. You can tell a lot by examining the fuse element. If it looks like “exploded” it was caused by a sudden large over current. It it just looks melted it was caused by small over current for an extended time OR bad connection transferring heat into the fuse.

Check all of your connections in the box. Check the elements in your tank. You may find the problem is the tank after replace the box.

Let us know what you find.

Just to follow up I have put a new 30 amp breaker (Recommended for my unit) in the breaker box and ran new 10-2 w/ ground wire from the breaker to the Water heater(about 15 feet}. I will watch the performance of the Water Heater but have a good feeling all is fine NOW. I really don't know how my Grandfather thought 12-2 wire on 40amp breaker and 25 amp fuse box switch was good idea?? To be fair the fuse box i was using spent 40 years in a old tool shed and maybe the Mice ruined it???? The Water Heater was never had a ground wire either??

 

[Hemmjo]

Just to follow up I have put a new 30 amp breaker (Recommended for my unit) in the breaker box and ran new 10-2 w/ ground wire from the breaker to the Water heater(about 15 feet}. I will watch the performance of the Water Heater but have a good feeling all is fine NOW. I really don't know how my Grandfather thought 12-2 wire on 40amp breaker and 25 amp fuse box switch was good idea?? To be fair the fuse box i was using spent 40 years in a old tool shed and maybe the Mice ruined it???? The Water Heater was never had a ground wire either??

That is a good solution.

"Back in the day" things like hot water tanks did not need to be grounded by the electric system. The steel or copper plumbing system served to ground the tanks. But then dielectric unions became required to prevent corrosion caused by the dissimilar metals in the tank and piping system and plastic piping makes proper grounding very important.

Mouse pee is very corrosive also. Electric boxes with unplugged knockout holes are perfect mouse houses!!!

 

[cleddy]

Dual element tank style heaters are factory setup to operate only one heating element at a time .

Top element first and after the top of the tank is up to temperature . Then the thermostat opens the circuit to the top element . And energizes the lower element .

Elements are usually 4800W however 3500W and 5300W heating elements do exist . They should draw approx 20, 14.5 and 22 amp.

I liked your information. I wanted to check the current flow but don't know how. My meter dosen't seem to have that option and I don't know which one to get-Is it the one that spans over the wire -current in question?