Failure!

Larry Weingarten

You do the work, suffer the pain and cost ... and we all benefit from the lessons learned! What a deal :~) I am curious to know how the Navien performs and holds up, as it looks like it could be good technology.

Thanks!

Yours, Larry

Rich Kontny_3

A Failure!

After 18 months with a demo unit hooked up to a"Heating Box" on an experimental basis I have indeed encountered a failure with the heat exchanger on the Takagi T-KD20 I will be returning it for it's autopsy. I see a great deal of corrosion on the top of the copper finned XH and suspect that is the problem.

This was a test unit with only my labor and materials as my cost. I will probaly go to the Navien high efficiency unit as my next test model.

Stay tuned!

Rich K.

Rich Kontny_3

Trial and Error

Larry,

This unit was exposed to some very tough conditions. Weather extremes outside from -10 to 100 (this creates differnt levels of condensate as the stainless vent really conducts cold to the top of the unit). The "Heating Box" add-on while hooked to a well insulated in floor zone does cause more cycling of the unit.

The other test system has a Rinnai Continum Tankless with a plastic outer sleeve and stainless interior exhaust
pipe. This seems to be working fine and the in-floor is a fairly large garage for a landscaper who stores his snowplows etc in there. Thus far he has had zero problems (knock on wood)

I know you are very well versed on hot water systems and I posted this for that reason. I was a little disappointed yet not entirely surprised as I also have very hard water that I bring down with a softener yet that is still not the most desirable for a tankless.

I tend to push things instaed of babying them. I want customers to have durable and reliable equipment.

Thanks Larry, you and your wife are assets to the industry.

Rich K.

Derheatmeister

Open system?

Is this a system that uses domestic waterheaters as a heatsource? And does it also supply the domestic hot water on the same system?(Interconnection)

Rich Kontny_3

Closed System

Der Heat... they offer the open system but I would not do that so I used their closed system. It is a packaged unit "the Heating Box" by Navien America. I have used both the Takagi and a Rinnai for heatsources on the two test systems I set up.I am kind of glad I was the one who had the failure not my friends son. Although he knows the situation and wanted to try this new heat source concept.