The pilot light keeps going off, even though the thermocouple has been replaced...what do I do now?

There are several possible causes for the described issue with your Empire BF-30-2 heater. Here are a few things to check:

1. Dirty or clogged burner: A dirty or clogged burner can cause the flame to diminish or go out. Make sure the burner is clean and free of any debris.
2. Low gas pressure: If the gas pressure is too low, it can cause the flame to diminish or go out. Check the gas pressure and make sure it's within the recommended range.
3. Faulty thermocouple: The thermocouple is a safety device that shuts off the gas supply if it detects that the pilot light is out. If the thermocouple is faulty, it could be shutting off the gas supply even though the pilot light is still lit. Check the thermocouple and replace it if necessary.
4. Faulty gas valve: The gas valve controls the flow of gas to the burner. If the gas valve is faulty, it may be shutting off the gas supply even though the pilot light is still lit. Check the gas valve and replace it if necessary.
5. Oxygen depletion sensor (ODS) tripped: The ODS is a safety feature that shuts off the heater if it detects a low oxygen level in the room. If the ODS has tripped, it could be shutting off the gas supply. Make sure the room is properly ventilated and reset the ODS if necessary.

If none of these solutions solve the problem, it's best to contact a qualified HVAC technician to diagnose and repair the issue.

Bad thermocouple.
this is what one looks like...
Honeywell CQ100A1021 18 Inch Replacement Thermocouple for Gas Furnaces...

1) Copy following link for resources:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#pilot

2) Gas control valve may be bad.
http://hometips.me/Mar/How-to-replace-water-heater-gas-valve.pdf

3) Add a comment Feb 2013 and say what you discover.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

If your pilot light will not stay lit when you release pilot light button then chances are that your thermocouple is bad. Make sure that the tip of thermocouple is directly in line with pilot light. Tip of thermocouple should be cherry red if it is properly placed. If pilot will not stay lit then replace it. If you aren't sure about placement of thermocouple you can heat thermocouple with a seperate heat source. If you do this and pilot light stays lit then reposition thermocouple in pilot flame. If it still won't keep pilot burning then replace thermocouple. Hope this helps. Thanks.

The pilot light jet may have got a little bit of dirt or grit in it which is preventing it from keeping alight. Try probing the jet with a fine piece of wire to see it the blockage can be dislodged. You may have to unscrew the jet to clear it by blowing air through it. Make sure gas is turned off first before removing any parts.

The pilot light also has a thermocouple that allows gas to the pilot light while the flame is burning. If flame goes out it shuts gas off to the pilot jet. The thermocouple is bypassed by a switch during the initial ignition and once the thermocouple warms up after a minute or two of holding in the bypass switch, it should maintain the pilot. If, after cleaning, the pilot light keeps going out, it would seem that your thermocouple is faulty and needs to be replaced

The pilot light jet may have got a little bit of dirt or grit in it which is preventing it from keeping alight. Try probing the jet with a fine piece of wire to see it the blockage can be dislodged. You may have to unscrew the jet to clear it by blowing air through it. Make sure gas is turned off first before removing any parts.

The pilot light also has a thermocouple that allows gas to the pilot light while the flame is burning. If flame goes out it shuts gas off to the pilot jet. The thermocouple is bypassed by a switch during the initial ignition and once the thermocouple warms up after a minute or two of holding in the bypass switch, it should maintain the pilot. If, after cleaning, the pilot light keeps going out, it would seem that your thermocouple is faulty and needs to be replaced

The pilot light has a thermocouple that allows gas to the pilot light while the flame is burning. If flame goes out it shuts gas off to the pilot jet. The thermocouple is bypassed by a switch during the initial ignition and once the thermocouple warms up after a minute or two of holding in the bypass switch, it should maintain the pilot. It seems that your thermocouple is faulty and needs to be replaced if pilot light keeps going out.

Hot water heaters that have problems with pilot lights going out are usually fixed by adjusting or replacing the thermocouple. The thermocouple is the brass tube that is in or near the flame of the pilot light. The thermocouple acts as a valve to allow the gas to flow to the pilot light. If the thermocouple begins to go bad, it may shut the gas flow off to the pilot light. There could be other gas supply issues, but this is about the least expensive first step for the home owner. REMEMBER, you are working with gas. Take your time and be safe or have a professional replace the thermocouple.

Make sure your pilot flame is hitting the thermocoupler. If not then use air to clean pilot port and try again.

Pilot lighted furnaces have a thermocouple made from disasimilar metals that when heated create electricity to actuate a relay that alows the gas to flow to the furnace.

When the thermocouple gets coated with carbon from the pilot lights constant burning it acts as an insulator and keeps the thermocouple from getting enough heat to generate electricity, a very good safety factor.

What you have to do is locate the thermocouple it should be located over the pilot light, you will see a gray substance around the thermocouple it will be hard like cement, take a knife and scrape away as much of the gray material as possible then sand the themocouple with a medium sandpaper until it shines, use one of you wifes emery boards, this should solve your problem.