[SmokebTp]

I recently got some info in here from some knowledged fellas about a 240 electrical heater I was hooking up and had great success in getting it hooked up and running. It has ran fine until about 3 days ago it started to throw the breaker. Its rated at 42.2 amps and was told with electrical heaters to rate them 125% which brought it to 52.75 amps. I wired it straight into the panel with 6 awg wire and am using a 60 amp breaker. Any ideas on why it would start tripping the breaker?. And do you think it was solve the problem if I stepped up to a 70 amp breaker or would this cause more problems or even worse be hazardous of fire?

[tkrussell]

Could be a defective breaker,or, more likely there is a loose connection at the breaker.

Do not just arbitrarily change the breaker to a 70 amp, that will require the wire to be replaced also.

Always a chance there is a short circuit in the feeder or heater.

[Missouri Bound]

If you can borrow a clamp on ammeter, you can determine what the load is while the heater is running. If you can determine what the actual heater load is, you can determine whether it's a heater issue or a breaker issue. Check for loose connections at the breaker, and signs of overheating with the wiring. (burnt insulation, darkening of the insulation) Double check your heater nameplate for the correct voltage and amperage. Do you have an owners manual with the specs? Was the breaker used for something else at one time? Does the breaker get hot to the touch when the heater is running? Let us know what you find out.

[kich1031]

You never want to upgrade the breaker... the breaker may be rated for 70 amps but the wire is only rated got 60 amps which means the wire will fail (catch fire, melt) before the breaker trips.

[wildandblue]

Be sure you have a new unit, not a factory reconditioned one that someone else returned because they had problems with it too. A 240 circuit is basically 2 120's side by side so I suspect there could be a short in your unit or in your wire where the two 120's are touching each other, or maybe a damp location where moisture is causing trouble? Sometimes the wire can get twisted being unwound from the coil, like an extension cord can get ruined by too much winding and unwinding.

[caibuadday]

Also when the heater doesnot disipate its own heat fast enough the breaker may trip

[tkrussell]

To clarify this statement:

also when the heater doesnot disipate its own heat fast enough the breaker may trip

A heating element that does not dissipate all of it's heat will not cause the load to increase at all, and cause a breaker to trip.

In this event of a heater not dissipating heat is caused by two typical problems, either the air flow is blocked by an obstruction, or the fan motor is not operating and forcing air over the elements. Either event will cause the heat to activate the High Temperature Limit switch, built into each electric heater, and shut down the power to the elements.

The breaker will not trip unless there is a short circuit or an overload.