PB error code on vita spa. Won’t heat up.... replaced heater. What should we check now?

have you checked heater? If you do not have the tools or skill, you may better served having it checked.

check and test heater

Also bad heater element.

Heater elements burned out.

I believe with some of manufacturers spas, Vita included, the error will occur if the system is reading that the pressure switch has a "CLOSED" circuit. Bypassing the pressure switch, will still be creating this! What this means to the system: The circuit board does a quick system check. If the board says to itself: "Why does the pressure switch tell me the water is flowing (thats what happens when the pump is on and moves water; pressure is created in the plumbing and the switch then closes) when I haven't even sent power to the pump yet?" Then it will send the error message.

Your switch may need to be calibrated to only close when there is water flowing, and then open within a second of the pump or water flow stopping.

Vita Spa Error code (PB) is a power board communication error. Turn off the power and then check the connection between the topside control and control box. check for loose or unplugged wires, unplug the topside control (after turning off the power) and check for signs of shorts or charring on the wiring ribbon/connectors. If you cannot find the source of the problem you will need to contact your dealer or repair technician. I hope this helps =)

Your problem is likely the heater element has failed.
The water is only reaching, mid 80's due to friction and heat from the pump. This is an intermediate problem, we recommend calling an spa technician. If you want to read: how to do to test a spa heater element.

Your problem then would be the pick up tubing and/or switch attached to the blower that closes once the blower is on to allow the heater to ignite. Pull the tubing and check it for dust or other debris clogging it and check inside the blower housing for the same. If you can test the switch under operation, you should see it remains open during start up which is why the burners won’t fire. If you do not find any obstruction (if you can, blow some compressed air thru too just to be sure) then you will need to replace the switch.