Boiler flush - how often? Power flush?

[GroundLoop]

Bought a home three years ago with two Raypak H3-01803 residential boilers. I know they are very old. Do not know when the previous owner had them serviced but they did look to be in good condition. Both systems are for radiant heat in a concrete slab. They are water based sealed systems. Just wanted to know is this something a handy person can themselves? Or should the system be power flushed? What is the typical flush interval? What is a typical price to pay for boiler flushing? Looking on google it says every year with the prices between $100 - $600. That does not seem correct to me.

Talked to my neighbor and he said if they are sealed systems then they should not need flushing. He mentioned possibly adding some scale prevention.

 

[Firebrick43]

If there isn't an air leak in the system you neighbor is probably right. A closed boiler loop with a microbubble air separator goes to near zero oxygen in the system and little to no corrosion happens . Flushing/replacing the water just adds oxygen back into the water plus any minerals that come with it to precipitate out.

Now if your system has an air leak and your constantly expelling air from the air separator then fix the leak.

 

[pcmeiners]

Firebrick is 100% correct. As long as water is not added to the system negligible corrosion/scale buildup occurs.

 

[fitter30]

Rectorseal 8 way boiler treatment is a good idea they sell it by the qt.

 

[GroundLoop]

Thank guys. Good info. Over the weekend I had to replace part of the metal drain line on one of the boilers, it had rusted apart. Lost a little water. How do I add water to it?

Plus when I had it apart I discovered this. System is almost 30 years old. Should this be replaced or fixed?