I am trying to heat an apartment building with 3 apartments with space heaters and a 40 amp heat box. It is an old building with old wiring and old screw in fuses and 100 amp fuse boxes for each unit. How do I know when I have overloaded the circuits? Can anyone offer a recommendation for this situation?

Space heaters are only temp heat uses, they are not for any long term or permanent heating use. What is the real heat system for the building.

The heat in the building is hot water radiator heat. This heating system will soon be replaced in 3-4 days. So in the mean time, space heaters, heat boxes,etc..?

Load em' till it pops!

This I am sure is not an electrician offering advice:


load em' till it pops!!

As we like to do things a bit more scientific.

Our goal is to prevent things from popping.

This prevents fire and loss of life and property.

And your goal is to heat the building, not change fuses.

Each of your temp heaters is rated in watts or amps.

A typical heater can be approx 1500 watts, or 12.5 amps.

Your old home should have mostly 15 amp circuits, so one 1500 watt heater will operate on one 15 amp circuit.


The 40 amp heat box is a problem. Check to see if this needs 120 volts, or most likely 240 volts. In any case need to know a bit more about it before advising how to connect this. Why do you call it a "40 amp heat box? What is the nameplate rating in amps, volts, and watts?

I was told at the rental company that the "heat box" is a 40 amp unit. I plugged it into the electric 220 circuit plug in the kitchens. Thanks for your advice. I am learning!!