Should I upgrade the builder’s standard geothermal system?
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We decided to do a “semi-” custom house for our latest project. The builder/developer requires each home to have a Bosch geothermal system. I wouldn’t select geothermal if given a choice, but…
The spec’d system is a Greensource i Series BP. It is my understanding that this one of the older systems made by Florida Heat Pump (the company acquired by Bosch). Except for the smallest system, all the BPs use an ECM fan. My concern is the single-stage compressor. Wouldn’t a two-stage compressor, such as offered on the CE series, be better?
I’m trying to pick my battles with this build.
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Sometimes it's better to go with the developer's standard, if only to get better experienced support for the system, even if it's not what you'd choose for a one-off custom built house. If yours is the only non-conforming system in their project portfolio identifying and fixing any issues becomes your problem more than theirs.
When they have dozens of a particular type in the field they learn fairly how to debug and fix them, and may even be able to head off known problems before they happen.
Two stage systems are only an advantage when the systems are fairly perfectly sized for the loads, and loads are too seldom calculated with any accuracy. The difference in as-used efficiency between an oversized 2-stager and an oversized 1 stager are pretty academic. As long as it's not short cycling or the system design is grossly out of whack it'll still be pretty efficient.
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Thanks, Dana. That makes me feel better about going with the standard option.
Is it a shared loop?
Does it have to be Bosch?
I'd want internal variable water flow. Had an external flow center and I like the internal better.
I would be tempted to go with a variable speed compressor unit such as the Climate Masters Trilogy 45.
I believe each system is on its own closed ground loop but will double-check. Trying to switch to another brand would open up a can of worms. I have history with this builder and am trying to minimize changes to the specs so neither one of us has stroke. ;-)