Bad radiant in Seattle

Paul Pollets

I've seen dozens of these installs over the years...they may vary in equipment but all use the potable hot water heater as the heat source.The Rinnai tankless connects to the Heat Box for mixing and distribution. In this case, the mixed temp was trying to heat (1) fan coil unit in the basement and (3) loops of staple-up without plates on the upper level. The thermostat for the Basement was installed 3 feet directly above the FCU. Shall we say short-cycle? Non-barrier AquaPex was used for all distribution. The setup requires an RPZ backflow device, but none was installed.

FYI, I refused to do any work on the system, unless it was replacement. I referred the owner to the local Rinnai rep as I don't want the liability for this system working correctly.

DanHolohan

But he got a good price.

Right, Paul? That's all that matters, isn't it?

Harvey Ramer

Maybe?

Or maybe he made a small investment in a big price?



Harvey

Paul Pollets

The Price is Right

Ahhhh, yes. But this is no game show....The price was too low for the builder to refuse. Now all the townhomes are plagued with yukky systems.

Robert O'Brien

Not radiant

But I saw another tankless failing as a boiler in Locust Valley NY today. Using it as a backup to a solar DHW/Heat system. Unfortunately the distribution is hydroair and the Rinnai can't get the water temp up enough at outdoor temps below 20*. The electric tankless did but at a cost of $1600/month! Very bad application of solar in a high temp system