What threading is the Takagi filter - need to flush via it - TK-03-os

[TheOverThinker]

I have a standard Takagi TK-03-os ( https://www.takagi.com/media/48120/T-K3-OS.pdf ) tankless unit.
I'd like to flush it, but there's no cleanout or valves.

However, I can do this if I can adapt and screw into the filter port.

Anyone done this, and know the size and threading of that port? Looks to be about 1/2, but the threading is unclear.

I know the part number of the filter is EKK2C. But what's the threading?

 

[Breplum]

Nobody has done it.
Sorry, you need to have a tankless water heater bypass valve kit installed. That's why they make them.
Just forget what you are contemplating.

 

[Sponsor]

 

[Fitter30]

3/4" national pipe thread is the heater connections