Navien CH-240 siphon hose leak, gas smell

Users who are viewing this thread

Joe B

Member
Messages
30
Reaction score
1
Points
8
Location
Oregon
Hi everyone,

Could a leaking siphon tube also result in gas escaping from a Navien CH-240 boiler?

I know - Naviens are fussy. But my CH-240 from back in 2010 has been humming along until just the other day. I found that it has begun leaking from the top of the "siphon hose" where it connects to the bottom of the burner.

2024-03-12 18.00.10 copy.jpeg
2024-03-12 20.08.52 copy.jpeg
2024-03-12 20.30.32 copy.jpeg


I drained the condensate trap and refilled the siphon per the manual. But, it still leaks. I have a replacement part on order.

However, when running DHW with the case open to check the leak, I noticed a gas smell for the first time ever. Checked with my cheap gas detection tool and there is indeed gas in the garage where the unit resides. After airing out the garage, I ran it again with the case closed, and I did not smell gas, but my tool did detect a little by the unit.

Could the leaking siphon hose be the source of the gas? Or dare I begin to suspect a worse problem?

(Have any of you experienced this siphon hose tube leaking?)
 

Joe B

Member
Messages
30
Reaction score
1
Points
8
Location
Oregon
The aluminum output nozzle that the black siphon hose connects to has completely disintegrated. Perhaps this is why the model years that came after mine are now plastic on the bottom!

It's too bad, this Navien has been operating pretty well for 13 years.

Looks like I am getting a new combi-boiler (we have both radiant and DHW).
 

Joe B

Member
Messages
30
Reaction score
1
Points
8
Location
Oregon
Just fyi, my tech put in a temporary fix while we figure out a plan. He put in a little copper pipe stub, sealed it, and reattached a new replacement siphon hose that I had on hand. Just a short term fix to keep things operating.
 

Jeff H Young

In the Trades
Messages
9,593
Reaction score
2,420
Points
113
Location
92346
dosent sound too bad I might tinker with the condensate and attempt to find /repair gas leak. but ignoring gas leak not so good idea , sevice life 13 years not bad but might be able to strech that out
 

GReynolds929

Active Member
Messages
443
Reaction score
153
Points
43
Location
WA
Yes it can cause gas to escape the burner when the unit is operating.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks