Bought replacement goodman package HP with 20kw heater element. Old HP had 1 breaker and 6g wire to the service panel.new one has 2 breakers. will I need run 2nd run to service panel

It requires a 2 pole ganged breaker to meet code and guarantee the breaker is on two legs of the single split phase service. That in itself doesn't explain the 120 volts at the heater element.

Replace the two single breakers with the appropriate 2 pole ganged breaker. Before connecting the feed to the heater, turn on the ganged breaker and measure voltage across the breaker. If not 240VAC then there is a problem at the breaker panel.

If there's 240 at the breaker then you've somehow wired the thermostat incorrectly but can't imagine what you did.

Hope this helps..I have also attached a link that may be useful.

No Hot Water
REASON REMEDY No power Check fuses or circuit breaker, replace or reset. Check with utility if necessary Wrong wiring connections at heater terminal Correct according to manufacturer's instructions Leaks around heating elements (1) Tighten element (2) If necessary, clean and replace with new gasket Loose wiring connection Locate loose connections. Clean carefully (remove all oxidation). Reconnect properly Lightning Inspect: (1) fuse (or circuit breaker). (2) Heater elements, and (3) thermostat, replace if necessary, see "grounding instructions" below High voltage Check utility for correction Short Locate short circuit and correct Wrong piping connections Reconnect pipes to proper fittings according to manufacturer's instructions Undersize service wiring Check with utility co. or electrician Improper calibration Replace thermostat Faulty thermostat Replace Faulty thermal cutout Replace Open thermal cutout Reset Top heating element burned out Replace
http://www.bradfordwhite.com/sites/default/files/product_literature/48494-A.pdf

1) Test elements, and if elements are good, then replace both thermostats.
Takes about 20 minutes. Power is off.
http://waterheatertimer.org/How-to-test-water-heater-element.html
http://waterheatertimer.org/How-to-replace-thermostat-on-electric-water-heater.html

2) Label on side of water heater shows volts and watts.
For 4500 watt elements, you need 30 amp breaker and 10 gauge wire.
Move water heater wires to different same-size breaker.
http://waterheatertimer.org/Color-codewire.html

3) Open the links and do the work, or call plumber to do work, or call manufacturer for warranty coverage.
If your wire and breaker are problematic, then service is not free.

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

1-888-593-9988. Goodman tech support. Have your model and serial numbers. The black wire should be L1 to the heat element, but the pink wire? No telling without seeing the schematic.

do any one have a old package unit is a goodman i want to see were heater on that package uint or take picture of that unit so i can see where the wire go at the heat

There seem to be several questions mingled in with those 2 questions.

1) Amps can go either way

2) Breakers trip when heat exceeds certain level. Heat is caused by amps.

3) You want to add a subpanel in garage.
I do not know the code in your area for installing a subpanel.
Your plan will work by connecting 6 gauge wire to main breaker, and new 60 amp breaker will protect wires between main box and subpanel.
Remember, wires going into main breaker cannot be turned off without pulling meter.
Some areas require license to pull meter.
http://waterheatertimer.org/How-to-replace-circuit-breaker.html

4) To work around license and meter-pull, simply replace a 240V breaker in main panel with your new 60 amp breaker.
Then move breakers around to match new set-up.
New subpanel can accommodate two new 240V breakers and one new 120 Breaker
http://waterheatertimer.org/How-to-install-a-subpanel.html

5) 6 gauge wire is correct for 60 amp breaker.

6) I'm not sure what you mean by the box rails?

7) Do you need more amperage on main service?
This means adding a larger service panel with 150 Watt or 200 Watt main breaker.
Some areas require service upgrade when remodeling or adding circuits.

8) How to figure total amp draw at your house.
Add up total watts being used.
For example you have 1/2 Hp motor
754 watts per Hp
1/2 Hp = 377Watts
Volts x Amps = Watts
Amps = Watts divided by Volts.
377 Watts divided by 240Volts = 1.57 amps (plus a bit more amperage when motor starts)
40 watt light bulb divided by 120Volts = .33 amps
Double oven has label located inside door that shows upper and lower wattage.
Dishwasher, dryer, big screen TV, satellite receiver all have labels that show wattage.
Water heater has label that shows wattage of each element.
http://waterheatertimer.org/Figure-Volts-Amps-Watts-for-water-heater.html
http://waterheatertimer.org/See-inside-main-breaker-box.html

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Breaker must be 2 to 3 times of running amps of a/c or heater whichever is higher. If breaker fixed minimum3 years back, better to replace. In heater, clean heater strips by a blower and also check for loose contacts. Sometimes weak strip element, it may happens. Replace heater element. Thanks.

You have electric water heater.
You replaced elements and thermostats but heater still won't work.
And tank was completely full of water, and water was running out of a faucet before turning power ON.
If elements are not fully immersed in water, they will instantly burn out.
If upper element is burned out, then tank will have NO hot water.
If lower element is burned out, and upper element is not burned out, then tank will have some hot water.
http://waterheatertimer.org/How-to-test-water-heater-element.html
http://waterheatertimer.org/How-it-works.html

If elements did not burn out, then that leaves 1 main suspect: the electricity.

1) Push in ECO red reset button on upper thermostat. If ECO is tripped out, then heater will not work.

2) Click circuit breaker all the way one direction and then back the other direction to make sure breaker is latched.

3) If tank has 2 elements, then it is 240volt.
If 1 leg of 240Volt circuit is not working, then 240V appliance will not work.
240Volt circuit needs both hot wires to complete the circuit:
http://waterheatertimer.org/How-to-wire-EH40-hot-water-heater-timer.html#120-240

Buy cheap multimeter from Home Center and set dial to 240-250-277VAC
Tape tester leads to woods sticks to keep hands away from power.
Power is ON
Test across top 2 screws on upper element should show 220-240 volts.
If you have 240 at top two screws, then skip down to step 6.
If no reading across top two screws, then move to top of tank.

4) Open connection point where wire connects to heater.
Test across both insulated wires should get reading of 220-240 volts.
If no reading, move to circuit breaker box.

5) Mark water heater breaker.
Turn off all breakers except water heater breaker and main breaker. (and breaker to light fixture where box is located)
Do not hold or touch or lean against anything metal.
Stand on dry boards and wear dry clothes.
If main breaker is OFF, the big wires that connect to main breaker are still HOT.

Remove box cover.
240Volt breaker has 2 wires connected with screws.
Test across both screws for 240Volt.
See if wires are loose.
If there is no reading, then breaker is not working on one leg.
To double check, move water heater wires to another same-size 240V breaker and then put ear against water heater to listen for bubbly-fizzing sound.

6) If you are getting 240 to water heater, then wire inside tank could be loose.
Do 30 minute troubleshoot:
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html

Add a comment for more free help.
Also take advantage of fixya phone service.
For a price, fixya expert speaks with you over phone while you work on timer.

I assume this is a 240 volt water heater that runs on a 30 amp circuit. Read the instructions that came with the new water heater to be sure. If the wires are connected correctly then you have a defective water heater. Let's first make sure it is wired correctly. Turn the breaker off and take a look at it. It must be a 30 Amp breaker and the wires going to the water heater must be 10/2 with ground. This is an orange wire. If you cannot see the water heater from the service panel it must be wired to a disconnect box. Look at the breaker and make sure the red & black wires are tightly connected to the double pole breaker and the copper wire is connected to the ground bar. At the disconnect box (if applicable) the red/black wires from the service panel must be connect to LINE and ground to ground bar. The wire going to the water heater from the disconnect box is connected to LOAD. It is easy to get these mixed up because they are not always in the same location and are hard to read on some disconnect boxes. Look carefully and make sure they are correct. At the water heater you connect Black to Black and Red to Red. Make sure the ground is connected tightly and none of the wires are touching each other. Use wire nuts and then tape the connections with electrical tape. You should not have applied power to the water heater until it was full of water. If you did then your burnt out the electrodes. I would suspect you have a short somewhere or the water heater is defective.

Everything above tells me this is 120V unit...if thats the case a single pole breaker is sufficient. Also by what you have written, a 15 amp breaker should suffice.