Best Of

I have the same setup as you are suggesting except my Viessmann (V.) is a 100 series. No need for the 200 unless you have lots of peripheral equipment (mixing valves, solar, etc.).

I service many V. boilers in the City, East Bay, Marin and South Bay and stock the most common replacement parts as, unfortunately, parts are not available locally. I urge my customers to stock these parts there, with the boiler in case I run out or if they call in someone else for repairs.

The 120 gallon indirect sounds too big for you. I’d go with the 80 gallon. V. has the best stainless indirects. None of the ones I’ve installed over the last 40 years have failed.

Lochinvar also makes a great boiler and they, along with V. have good technical support.

Edit:

"In looking back and with current research it seems my installer did not account for the value of stored thermal mass even though I have a decent size mechanical room."

Stored thermal mass? I don't understand.

"I’m also considering 2-3 solar thermal panels now or in the future."

Oh, I see. The solar add on is why you wanted the 200 Vitodens. I'd skip the solar thermal. Too expensive to maintain and repair. Solar electric is a better option.

Depends on your craftsmanship and ability to source components. If you can find the correct components and your design and craftsmanship are up to what Caleffi or some others can do, yours and pre-made will be equal. Yours will probably be more expensive, quality for quality.

Air to water heat pumps are common in that area, climate is a good match, incentives are available.

Corey Page posts a lot of HP conversation on his IG account, in that area

"Point arrow towards wall" means do not point to floor or ceiling. IMO

Horizontal shaft position only. Some may have been confused by "Horizontal" and "Vertical" wording.

I have a 1961 school with 2 pumps similar to this. Both original motors still working.

Rinnai combi unit. Pretty darn good. Givem a look.

As @delcrossv and @mattmia2 say, with a little oil (don't overdo it) and some attention to the motor mounts, that thing will run another century or so without problems. The coupler springs are the weakest part, and paying attention to the mounts will keep hem happy.

And the same pump is still made. Don't mess with success…

Oh and one more thing: it's within a percentage point or two of any "modern" pump in terms of efficiency.

You might contact the B&G rep in Seattle, CHC, see if they have the motor mounts and spring coupling. They would probably have a motor that fits also, if you want to buy a spare. Replacing that entire pump with another 4 bolt type may be expensive. Or changing flanges and piping with that insulation may be a lot to get into.

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