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Water Heater Keeps Blowing Fuses

Water Heater Keeps Blowing Fuses

Wondering why your water heater keeps blowing fuses. It may not be as simple as you think. Let us help you with some suggestions from the professionals.

The top reason your water heater fuse keeps blowing is because of heat. The heat is built up by old loose connections. The connections then start to arc. This causes the fuse to blow.

9 Reasons Your Water Heater Keeps Blowing Fuses

  1. Bad Connections
  2. Poor Wiring
  3. Bad Fuse Holder
  4. Bad Element
  5. Faulty Disconnect Box
  6. Undersized Wiring
  7. Age Of Tank
  8. Problems With Thermostat
  9. General Maintenance

Why Does My Water Heater Keeps Blowing Fuses?

Bad Connections.

Bad connections are common reason why your fuse would keep blowing for your hot water tank.

Loose connections cause arcing which will cause the fuse to blow.

Make sure you have a certified electrician to wire the hot water tank instead of Joe blow do it yourself handyman.

water heater keeps blowing fuses

If you do not have tight important connections done then you will most likely run into problems.

We recommend that you tell your electrician you want to minimize connections as much as possible.

The more junction boxes, breaker connections, fuse connections and wire connecters that you have.

Will most likely cause more issues for the fuse or breaker to blow from loose connections.

Minimize as much as possible and be 100% certain that the connections are completely tight.

Water Heater Keeps Blowing Fuses Right Away

2. Poor Wiring.

Poor wiring can result in the fuse or breaker tripping or blowing to your hot water tank.

As mentioned above connections are the key.

If the connections are not tight and you will have a problem. It is also very important to have the wire size correct.

If the wires not size correct it can also cause issues.

If the wire so small and the breaker is too small then you will have continuous tripping the breaker will reach it’s maximum capacity.

Again this is important to have done by certified local electrician.

Why Does It Only Do It Once and A While?

3. Bad Fuse Holder.

These are the key to causing issues when it comes to your fuse blowing on your hot water tank.

You could have loose connections into the fuse panel.

Inside a fuse holder there a metal contact apps. These metal contacts become worn over time.

They must be adjusting or cleaned up with sandpaper to make a contact.

When they do not make a contact a result in a fuse heating up.

This results in the fuse blowing which is also why this happens periodically or time to time. It can be very frustrating as a homeowner.

As a homeowner you can install time delay fuses instead of a one time fuse. A one time fuse detects a short circuit which causes the blow instantaneously.

Time delay fuses will work for a fraction of time for the heat to build up so it does not blow the fuse.

We use time delay fuses on motors and applications similar applications all the time.

This allows for inrush current from the motor so they do not continuously blow.

Make sure when you screw the fuse that it is completely tight in the holder.

It will help keep heat from building up.

Watch Video Here

Water Heater Keeps Tripping The Breaker

4.Bad Element.

A bad element can definitely be the culprit.

Since the element is submerged in water. If the internal part of the element becomes exposed to the water.

This causes a dead short to ground. This will give you an instantaneous trip on your breaker and you should not keep resetting it.

You should call a professional or local electrician to come identify the problem and replace the element or the breaker.

Not all electricians will replace that element. Sometimes it is better to get your local plumber to replace the element for you.

The element can be checked by completely shutting the power off to the hot water tank.

Step two would be to remove the wires directly off of the elements and then do a resistance check of the element itself.

You should get a resistance reading. If you get nothing this is a sure sign of the element is open or is not working.

water heater keeps blowing fuses

The Shut Off Box Next To My Tank Keeps Blowing The Fuse

5. Bad Disconnect Box.

We get this service call more often than not. Do you have an old disconnect box next to your hot water tank?

This is installed as a service box so the equipment can be serviced by repair man.

Unfortunately these boxes wear out overtime.

This causes heat with inside of this box which causes a fuse to blow. The connection becomes loose and then causes arcing within the fuse. This is when you will need an electrician to replace his box for you.

The Wiring Needs To Be The Right Size For The Tank?

6. Undersized Wiring.

Correct we always try to wire correctly for the hot water tank.

For standard 40 gallon hot water tank with 3000 W elements your require a piece of 12 to gauge wire which is rated at 20 A.

This actually draws about 12 1/2 A when the hot water tank is heating.

For a 60 gallon hot water tank with 4500 W elements and he will need a piece of 10 gauge wire which should be on a 30 amp breaker.

The 4500 watt elements will draw up to 18 to 20 A.

Which is too much for your standard 20 amp circuit.

If you try to install a 60 gallon tank where there was a 40 before then you’ll most likely need to upsize the wire.

If you leave the smaller wire in place this will max out the circuit caused the fuse or breaker to keep tripping.

Remember this because this is very important.

As electricians we are only allowed to go to 80% of the circuit capacity.

This means we can only load the circuit up to 80% out of 100.

As an example if we have a 20 amp circuit and technically we can only load it up to 16 A.

This makes a 60 gallon hot water tank too large for a 20 amp circuit because you can draw 18 to 19 amps.

You may need to go up to 10 gauge wire size to allow for this so it can difference in amperage.

We can legally go up to 24 A on a 30 amp circuit. Learn More on Recommended Hot Water Tanks Here

How Old Is Your Tank?

7. Age Of Tank

Believe it or not the life expectancy of an average electric hot water tank is 5 to 7 years.

They rate them like this because they are installed in different locations and different situation in everyone’s house.

If you have them in a dry warm area that he will most likely get your full lifespan.

If they’re in a damn basement in the lifespan would be less. In addition to this if you have water conditioning issues or poor water quality and this will significantly shorten the life of your hot water tank.

As it can eat out the inside of the tank and cause leaking issues or not to work at all.

Thermostat Chatter?

8. Problems With Thermostat.

Inside of the hot water tank there are actually two thermostats. There is one for the upper element.

There is also one for the lower element.

The thermostats can malfunction and cause chattering at the setpoint.

What we mean by chattering is that it shuts the elements off and on continuously because of the malfunction of the thermostat.

This natural causes arcing with the internal part of the circuit which will then cause a fuse or breaker to blow.

Furthermore the thermostat will stop working altogether or stick on which is even worse.

This can cause your tank to overheat.

In this case you’ll notice the pressure release valve blowing off steam from the top of the tank. This is a sure sign that you have a faulty or stuck on thermostat.

Thermostat can only switch on and off so many times before it becomes

worn out.

water heater keeps blowing fuses

How Do You Prevent The Fuse Or Breaker from Blowing?

9. General Maintenance.

General maintenance is the key to having a healthy hot water tank.

Make sure you have a professional installer do this for you.

Be sure all the connections are correct.

Make sure it is installed in an ideal dry warm location. Additionally you may want to install a bladder underneath the tank in case it ever leaks so you do not have water on your floor.

Make sure your water quality is good so that you do not have problems with inside the tank.

All the factors play into what is it used or breaker will trip.