As concerns standby loss, I can't speak to the others, but the Rinnai has a
simple on/off button on the front of the unit. A remote controller is available
which also provides the switch. It does take afew seconds for the unit to boot
up. Up to three remotes may be installed, making the on /off operation and
temperature adjustment fairly convenient.

Been using a Rinnai here, on grid for 10 years or so. It works. We like it.

I understand a pilot uses a significant amount of gas over the course of a year.
Just sayin'.

Dick Ratico
Solarwind Electric

--- You wrote:
If its a Rinai, I measured one once that was 30 watts AC standby, and 
jumped a bit higher when firing.  It also needed pure sine.
The customer swapped it for a regular hot water tank.
Some Bosches and old Palomas, etc. had either a piezo ignition or pilot, 
but took no power.
I'm working on a system with one now that needs 12vdc at about 5 watts.

R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified PV Installer,
Licensed Master Electrician
Solar Design Engineer
303 505-8760
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