Re: New paradigm for home heating automation and control

[Marc F Hult <MFHult@xxxxxxxxxxxxxxxxxxxxx>]

On Mon, 19 Dec 2005 21:37:00 -0500, "Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>
wrote in message  <ca-dnfCO7PDf8jreRVn-rQ@xxxxxxx>:

>It does give rise to an interesting question:  Does it pay to have two types
>of heating systems if there's a tremendous flux in availability of fuel
>sources?  How would that be manageable from an HA standpoint?

In the example of the upstairs furnace in my house that died, my current
thought is not to replace the gas burner at this time. (Estimates I've obtained
for a  high efficiency gas furnace + AC + heat pump are $10-12K :-(

I may end up with four heat sources in the same air handler ("furnace"):

Natural gas burner
Heat pump
Resistance ("strip") heater
Hot water (via water-to-air heat exchanger)

The hot water in turn could be derived from the currently existing boiler in
the basement, and(or) another heating plant which might be in an out-building
burning a solid fuel.

My first repair will be to re-examine insulation and other energy conservation
measures.

The second repair/conversion will likely be to put a water-to-air heat
exchanger in the housing that previously contained the electrostatic air
filter. This is practical because the heat source for the air handler in the
basement is already from a big ol' Weil-McLain boiler via a heat exchanger so I
'just' need to get the hot water from the basement to the attic -- easier said
than done in a house with solid brick interior walls. (I got to be pretty good
sweating  1-1/4 copper pipe when I redid the heating in our stone Victorian
house in Minnesota starting 20+ years ago during the _last_ energy credit
hoopla.)

The exercise of installing the water pipes will also provide the
incentive/opportunity to replace the last length of aluminum wiring in the
house, add a second floor load center, and re-commence the hardwired lighting
of the second and third floors.

Managing this from a HA perspective will be interesting in part because
near-monthly changes in energy costs will be the norm for the foreseeable
future. So a 'thermostat' in the scenario I've outlined needs to have energy
cost inputs and competition include in the real-time calculations. I say
"competition" because not all energy sources are available _ad_libitum_ at all
times. For example, I will not upgrade the 200amp electrical service. So that
200x240 VA source for all house electrical is a boundary condition. And so on.

Add humidity control, geo, summer AC needs, etc and this is looking to be a
very long term project. The HA software (CyberHouse) I sue was the only HA
software that I am aware of to integrate electrical energy cost and energy
management -- done via a Cutler Hammer Advanced Power System:
http://www.eatonelectrical.com/NASApp/cs/ContentServer?pagename=C-H/Common
/AssetTemplateLink&c=Apubarticles&cid=983558184807&Sec=products

... Marc
Marc_F_Hult
www.ECOntrol.org