Really easy to do if you have purge/flushing T’s installed at the plate exchangers.
I use a puddle pump with a garden hose adapter on it and two short pieces of garden hose. I used to use washing machine hose but garden hose will flow more.
Place the puddle pump in the bucket, connect your hoses with the return in the bucket, dump in a gallon of cleaning vinegar and let circulate. If done yearly usually a gallon is plenty. I have two in my basement, when done I add fresh water to the bucket and let the vinegar flow down the drain to the septic tank.