Jac04
Member
Back on 9-18-17, I had new Navien NCB-180E combi boiler installed at my house. It replaced a 4-year-old CH180 unit.
Background: The CH180 unit always (from day 1) had grey colored condensate, and the trap always had heavy grey/black sludge in it. Navien told me this was normal, but the outer casing of the heat exchanger failed after 4 years. The grey/black material turned out to be the outer aluminum housing of the heat exchanger corroding away.
OK, back to the 1-year-old NCB-180E. After installation, I cleaned the condensate trap a few times over the first few weeks and found nothing but a few shavings leftover from when the intake & exhaust PVC pipes were cut. The condensate was clear, and I was relieved.
I checked the condensate trap on 2-25-18 and found some sediment (see pictures). I didn't think too much of it at the time, as there was very little sidement. I saved the sediment, cleaned the trap & re-installed it.
I checked the trap on 4-25-18 and found more sediment (see pictures).
Here's my concern - the sediment is magnetic! The only magnetic parts that are in contact with the condensate are inside the heat exchanger (as some of the stainless heat exchanger parts are made from a magnetic grade of stainless steel). My concern is that the heat exchanger on this unit is slowly corroding away, just like the fist unit.
The intake screen is clean. The condensate water is crystal clear. Being on the condensate (combustion) side of the heat exchanger, this issue is independent of the water being supplied to the unit.
What do you guys think? Is this a problem? Normal?
Thanks, Jeff
Background: The CH180 unit always (from day 1) had grey colored condensate, and the trap always had heavy grey/black sludge in it. Navien told me this was normal, but the outer casing of the heat exchanger failed after 4 years. The grey/black material turned out to be the outer aluminum housing of the heat exchanger corroding away.
OK, back to the 1-year-old NCB-180E. After installation, I cleaned the condensate trap a few times over the first few weeks and found nothing but a few shavings leftover from when the intake & exhaust PVC pipes were cut. The condensate was clear, and I was relieved.
I checked the condensate trap on 2-25-18 and found some sediment (see pictures). I didn't think too much of it at the time, as there was very little sidement. I saved the sediment, cleaned the trap & re-installed it.
I checked the trap on 4-25-18 and found more sediment (see pictures).
Here's my concern - the sediment is magnetic! The only magnetic parts that are in contact with the condensate are inside the heat exchanger (as some of the stainless heat exchanger parts are made from a magnetic grade of stainless steel). My concern is that the heat exchanger on this unit is slowly corroding away, just like the fist unit.
The intake screen is clean. The condensate water is crystal clear. Being on the condensate (combustion) side of the heat exchanger, this issue is independent of the water being supplied to the unit.
What do you guys think? Is this a problem? Normal?
Thanks, Jeff
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