Change in plans

We are going to go with the Takagi tankless heaters (the ones our builder is used to using) instead of the Rinnai - I think the main reason being our builder's comfort level and some venting requirements. He said the Takagi have done well in the homes he's built and he's had no complaints.
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I think we are going to use the Flash T-K3, as it is their "smallest, most versatile and most powerful residential model". You can also hook them together in parallel like the Rinnai models, so hopefully we can still maintain that functionality. If for whatever reason we do not, we can divide up the load fairly equally between the two of them pretty easily.
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http://www.takagi.com/web2003/tk3.htm
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The only concern that I have is the lack of a warranty due to being installed on a well setup, but he hasn't had any problems with well water in the area so far and they have been OK past their normal warranty period.
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