Navien tankless

[Gasg]

Hi
Does anyone know what's this condescending looking moisture that's forming at the bottom of heat exchanger? 
Has this brown colour and a bit of oily smell.
Navien tankless water heater
About 5 years old

[Porcupinepuffer]

Condescending? Is this boiler being rude again? I assume you mean condensing. Can't say I've ever seen one that looked like this before. It certainly looks clean inside with the exception of the condensate leak. I'd first take apart the entire drain line and clean it all out to rule out any crud buildup causing the condensate to rise higher in the pan. After that I would be looking at the gasket for that condensate pan as the culprit, or having a crack in it. The heat exchanger is likely due for a good cleaning. I'd have an hvac tech do a maintenance on it with a combustion analysis.

[Gasg]

Yes, condensing, sorry for typo.
Thanks for the tips!

Anyone else seen this/similar ?

[samihabib]

Yeaaaa that's the infamous navien combustion gas leak inside the chamber ..that's not condensation ..that the plastic parts of the HX getting so hot that it start excrete it's oils ..that's a unit to be condemned and replaced

[Sergroum]

Yup.  Seen that before.  Ive had it blamed on different things. From sucking in construction sand to lack of descaling after two years.  But when you start seeing sticky dark oil stains seeping from the seams of the heat exchanger, you are in for some expenses.

[tenletters]

It falls under their manufacturer defect. Even if the exchanger isn't covered, they still send a new kit for free. I've done several. The contractor has to take a bunch of pictures to get approved. This is how it was done at least a year ago when I was in residential.

They're pretty easy to change.