[heater99]

Do closed loop hydronic radiant heat systems need to have there water replaced every five years or so?

 

[danielworkerbee]

No, why would you ask ?
luck dan

 

[beenthere]

Nope, that would do more harm then good. By adding oxygen to the system along with the fresh water.

 

[sprintmj19]

There are contractors that tell homeowners their boiler and all of their radiators need "fresh" water every year. They actually add an extra charge to their clean and check for this.

Sad, huh?

 

[DGIO-Not]

Steam systems need to be blown down 30 days at the run: sludge needs to be flushed because constantly adding new water, minerals from water, oils are always there from installation or repair of steam pipes (unless properly skimmed.)

Hot Water systems, properly installed, should never need flushing, purging or water replaced, in fact could be determential.

"Been There" was correct, you did not give enough information on which to advise one way or the other. The upper two comments reflect this.

 

[zw17]

No, by adding more city water you are also introducing more heavy metals, minerals, and oxygen to the system, over time these are what cause deposits leading to issues.

 

[heaterman]

No, just the opposite. Old and flat (no bubbly) is good. As stated above, steam systems are the exception.