My appliance desires a 60 A 2 Pole, currently I enjoy 2 Pole tarnished beside a 30 on respectively side, is this indistinguishable? This is for a tankless water heater, it will draw a max...

This is for a tankless water heater, it will draw a max of 54 amps, can i use a 2 pole breaker next to 30 A on each side or do I need to correction it to 2 pole breaker with 60 A on each side. I become conscious that I might need to run new cable.
Yep.don't use that circuit with the low amp wiring. If you use a 60 amp breaker on that one you will asking for a fire. Those wires will warmness up and catch the walls or attic on fire. Once the fire inspector comes contained by to investigate why the fire started...he will notice the higher breaker on the low amp electrical system. Your insurance company will not pay you a penny for all the interrupt. I have a tankless hot water stove. You will absolutely need the 2-pole 60 amp. And a thicker calculate wire is also a good notion.
No, a 60 amp double pole is exactly that- 2 60 amp breakers tied together. Look at the picture in this Home Depot listing.

If you have a 30 amp circuit before, then you WILL stipulation new wire from the breaker to the oven.
Answers:    You have a 30 A. 2 Pole breaker.
You need a 60A. 2 Pole breaker.
You will entail #6 Cu. cable.
(Those poles are not additive. The current flows out
from one & back through the other at any given time.
You involve 60A. on both sides.)
You will need a 60 amp 240 volt breaker and should run a 6/3 with ground copper rope.