I am runnning a 4 ton earthlinked closed loop Geo system (In southeast Michigan) that is only used to heat the home, no water heating. My energy usage is running well over 200% more than the numbers the installer quoted. I have been monitoring my air temp at the plenum with a digital thermometer with an insertable probe. I'm running at a constant 98 degrees in first stage, as of February 1. Is this a normal temp for this system or should it be running at a higher temp. I know that Geo systems do not run as hot as conventional fuel systems, but I am wondering if this is contributing to my high electirc usage?

Return air temp is a factor. If you have something in the neighborhood of a 20* increase it could be fine. Do you know what percent of the load is handled by geo? Have you disconnected power to your 2nd (aux.) stage?
J

98 sounds OK, maybe even at the upper end of the typical range, 20-25 deg above return temp measured at the unit.

DX systems will give a 30 degree average rise so if your 68 and getting 98 its perfect on the temp side not high

what was the KWH per month and what area

A note of caution, a 30* rise for first stage of DX and 1 stage geo may be normal, though there are lots of provisos. A 20* rise for 1 of 2 stage water source or a tightly designed system (due to duct limitations in a retrofit system) might be normal as well. The general nature of the question causes us to answer generally.
j

The temp of the return air is 70*. The temp a the plenum is 98*. My KWH usage for the month of January was 3000KWH. The temp set at 69*.

This is all on a 2 year old home built with energy efficiency in mind. Well over R50 blown cellulose in the attic, blown cellulose in the walls, and very high energy efficient windows.

My Kwh usage for January with a HDD of 1658 was 2723 (includes appliances, water heater,lights ect) my house is 1500sqft R12 in my ceiling, energy efficient windows. We are north of Grand Rapids Mich.

You did raise a flag for me....1500 sf and a 4 ton seem unlikely. But heat load calc would determine that. Is this a ranch? Was a manual J load performed or was sizing guessed at?
J

joe my comments were for comparisions of his usage with mine but I have a 5 ton and I am not sure if a manual J was done, I hadn't even heard of that
method of determining heating/cooling loads before researching geothermal threads, they did use a geocomfort design studio program which gives a lot of information and for this am's temp of 7 deg it would be a space load of 44899 btu/hr and geo furnishing 44899 btu/h running 100%
mllewellyn didnt mention the size of his house or his HDD

Wirechief, I am heating a 3000 sq ft cape cod style home. We have 16 foot ceilings in the great room. The construction is about 2 years old with energy efficieny in mind during construction. No hot water heating thru GEO, just heat for the home. Have a dedicated GEO meter from DTE, so my readings are actual, not estimated.
Temp in the house is set at 69* with no set backs on the stat. What is "HDD"?

Wirechief,
Had my wires crossed. I mistook you for the original author, but with your clarification, I'm more at odds with your load vs sizing. Especially for cooling which should be a lighter load than heating. Was this retrofit or new build? Do you have 300 square inches of return air?
When I mentioned that the sizing seemed unlikely, it seems your system may be 1 or 2 sizes 2 large (based on the information you've provided).
I think it may work okay for you (with enough duct work), but I'm not excited about the design.
I also agree, that we don't have all the design info for author's system I think there is more in another thread. I notice you have started a thread as well, I'll add anymore thoughts i have on your system there.
J

Well my understanding is still progressing but it gives a temperature comparison that is done with the average high and low temps with respect to 65 degrees over a period of time and the number I used was for the month of January closest to my house. here is a link for better understanding.
http://www.degreedays.net/#generate and here is the link that I use for my area http://www.wunderground.com/, you could probably use your zip code and it will give you the details of your weather including the heating degree days, actually both links will provide that i just use the last one for my area. you could then do
a better comparison of Kwh used with a 3000 sq ft home is huge compared to mine but I would think for relative comparisons knowing the HDD is a good thing because you are putting in the same temperature averages just a larger home