Navien NCB-240E leak from air vent on circulation pump

Dsisson

I have a Navien NCB-240E combi boiler. It's leaking water from the circulation pump, pretty sure from the built in air vent. I can buy an entire circulation pump Navien 30015307A, but it looks like the air vent is removable. Possible to service this? I can't find the part for just the air vent.

Link to part: https://tanklessparts.com/product/navien-30015307a-circulation-pump-for-ncbe

Dsisson

Edit: I found this on aliexpress, but no idea if it's the right part:

https://aliexpress.us/item/3256803431441611.html?src=google&aff_fcid=9b9a02b5cd274c828db107ba760c97ec-1704268502015-08337-UneMJZVf&aff_fsk=UneMJZVf&aff_platform=aaf&sk=UneMJZVf&aff_trace_key=9b9a02b5cd274c828db107ba760c97ec-1704268502015-08337-UneMJZVf&terminal_id=31bb0ae1a32b4e808b78da4f9ca77ec9&afSmartRedirect=y&gatewayAdapt=glo2usa4itemAdapt

hot_rod

It could be a part specific to that Navian OEM pump. Or it could be the same on all the Grundfos supplied pump blocks.
Does Navian show it on the parts breakdown?

Some times disassembling it and cleaning the valve and seat will work.

Looks like some ugly water quality? Is it taking on a lot of fresh water?

Dsisson

I think it's been leaking for some time. I'm new to this boiler. Navien does not show it on the parts breakdown, just the entire pump w/air vent. Looks like Viessmann uses the same (or very very similar pump) and I can get Viessmann auto air vent 7828750, but not 100% sure it's the same part. I'll try pulling the air vent and see what happens. It's city water, and I think this is the only leak, so it's probably years of leaking. It is ugly.

dko

Use this part number: 30015225A

Dsisson

AWESOME! thank you!!!