Residential Geothermal Users Customer Reviews

by **757HomeOwner** » Mon Sep 14, 2009 5:25 am

Looking for customer reviews from people who have had residential geothermal heating and cooling for at least one winter and summer season. We think we're ready to sign a contract to replace current oil furnace and standard a/c units with 4-ton, 2-zone, 5-loop geo system. But it's a lot of money ($28,000) and after several hours of searching I've been unable to find any comments from other homeowners who have made the switch to geo to find out their opinion. We've done our homework and decided on the contractor. Anyone out there would like to share your satisfactin/disatisfaction/tips and tricks? Thanks.

by **Terry** » Sun Sep 20, 2009 6:34 pm

Funny you should ask. I'm in the Adirondacks of NY and my specific area sees lows of -30F. Last winter was my first full season for my heat-only geo sys in a newly constructed home and I was not very happy. I have a 7-loop horiz field with 5 radiant heat zones in 5700 sqft house (incl 1 in 2200 sqft unfinished basement), 1 zone for garage (big mistake) and 1 zone for workshop above garage.

All equip/mat'l were provided by Radiantmax (RM). I installed the field loops with the help of a plumber. This same plumber did all the pipework between the control board, Econar hp & pump pack, reservoir tank, and desuperheater to H/W tank. Elec connections were done by an electrician.

1st problem was ledgerock prevented me from trenching any deeper than 6'. RM owner came out to site and assured me it was deep enough. Next problem was hp did not work correctly for first 2 months. Lots of troubleshooting, reconnection of wires, etc. and it settled down and seemed to work correctly. During this I saw incoming fluid temp at around 35F in coldest months (vice 50F noted in literature). RM says that's OK as long as I see a 4-5 degree difference in outgoing temp. What I'm not sure of though is if hp efficiency is affected by having to extract the heat from colder liquid or if the main issue is just extracting the 4-5 degrees of heat.

My next issue was the system seemed to be running all the time. I have a 2 degree differential on my thermostats but it seemed to take no time at all for a zone to lose 2 degrees and kick on again. However, that may be due to a problem with the house structure and not the heating sys. I am having a home energy audit conducted soon to determine where I might be losing heat. So right now I am not sure if my expensive heating system is designed/working correctly or if I have a gaping hole somewhere in my house (which is not obvious by cold drafts, improper insulation, or any other sign).

As an elec engineer, geothermal theory makes sense and appeals to me. However, it did not make cents last year and it's not the kind of system that lends itself to an easy fix. In all honesty, I now wish I had put a less expensive system in and augmented it with a masonry heater. They cost about the same as a masonry fireplace but you only conduct 1-2 wood burns a day and enjoy the extremely efficient radiant heat output. I've been in 2 homes with these heaters and they are incredibly comfortable.

Hope this wasn't too long and wandering for you...

by **AMI Contracting** » Mon Sep 21, 2009 7:29 pm

Terry,
Sorry your experience has been unsatisfactory so far. It is a good example of the downside of hiring off-site geo engineers and inexperienced installers.
As you noted how quickly the house cools while the unit is not running is the house not the idle heat plants fault.
That said, if you find a local experienced pro to tweek things I expect you may have enough there to work with to improve your experience.

757
We've harped a lot that installer is more important than brand or type. Check references and credentials carefully. Run the proposal by us if you like.
The geo forum at Green building talk is headed by a thread with lots of individual experiences. We also have a new section here that will hopefully begin to fill up shortly.

I'd like to see you and Terry both enjoy your systems.
Perhaps Terry can start a thread with specific issues to address and you can share with us your heat load calcs and operating cost estimates from your dealer.
Luck to both of you.
Joe

by **Terry** » Tue Sep 22, 2009 7:32 pm

Joe,

At the risk of sounding defensive, I don't believe install is the problem. I have lots of pictures to show proper depth, width, and backfill of all trenches; and proper layout of HDPE "slinky" field tubing. Pressure testing prior to backfill also confirmed all heat fusion joints were leak free. Experience certainly counts but I spent a lot of time on the phone and internet to ensure proper install of the field loops. As for the in-house connections, the control board came preconfigured with all manifolds, circ pumps, in/out t-stats, etc. Any master elec & plumber should be capable of completing the wiring and piping (detailed elec & flow diagrams were provided). I knew I had only one shot at this and "anal" would be a mild description of how meticulous I was about installation.

I also believe my Econar pump is defective even though it eventually settled down. The pump would constantly lock out with an HP (high pressure) error. Radiantmax and a heat pump tech said that shouldn't happen in the heating mode. This is the problem that went away on its own so I am not confident the cause has been fixed. Also, due to a design miscommunication, my pump has a reversing valve for a cooling function. On several occasions, the reversing valve suddenly activated and put the pump into the COOLING mode when in the middle of the HEAT mode. This happened once while being inspected by a heat pump tech and he could not explain the mode switch. My ultimate solution was to deenergize the reversing valve relay by disconnecting the wire. That is not a real fix and is something I continue to pursue with Radiantmax.

As for heat delivery, I have 1/2" radiant heat PEX laid into aluminum plates stapled to 3/4"T x 7"W OSB installed at 8" O.C. with a 7" offset from exterior walls. Finished flooring is 3/4" x 2-3/4" hardwood flooring or tile.

I would love to get a geo expert in here but I am very close to being the first person in my area to install a geo system. A new company is starting up in my area but they do not use Econar and seem to be reluctant to look at some else's system. Radiantmax will come out but, at a 5-1/2 hour drive each way, the visit isn't cheap.

I did confirm from Econar that the incoming temp of my geo fluid is not an issue. I have a 2-stage GW980 and the literature provides performance data for an EWT of 32 deg F. I will be more than happy to start a separate thread as I continue to troubleshoot. Thanks...

by **AMI Contracting** » Thu Sep 24, 2009 8:40 am

Terry,
your own thread sounds like something many could benefit from.
The downside...installer/offsite engineer....I mentioned is what happens when something goes wrong, who's responsible. Reversing valve problems etc. would normally be warranty concerns but you have no labor warranty. Further a pro who does come out will have to charge extra time just to rule out installer malfunction. On top of that I don't have to tell you RM is not bargain basement.
That said, we will help if we can and you sound like you don't have too much ego in this for us to communicate freely about different possibilities.
Check the IGSHPA (international ground source heat pump association) web site as well as this one to see if you have an older pro nearby. Newbies might be talented or might not be and we don't want to further muddy the water if we can avoid it.
If you haven't yet contact Econar for support as well.
Reversing valve (if it is being mysteriously energized vs losing signal)has me suspicious of P/C board,thermostat or thermostat wire. Start with the wire it's cheapest. Having an extra circuit board around wouldn't kill you if you want to change it just because and thermostat can be under $100.
Good Luck, Joe

by **mark1745** » Sat Oct 03, 2009 9:44 pm

I have a Water Furnace split system 6 ton, closed loop, six wells 200 feet each. This was retrofitted to a existing Carrier HE propane furnace. We live in Minnesota the house is 8 years old, 5000sqft, lots of windows. In other words this house is a energy pig.

We’ve had great luck. 1st year winter savings $ 7,750.00 vs. propane. This number will change with propane costs / gallon, but the last year I was on propane I used $9088.00 for the season 2.50-3.69 / gallon. Geo operating costs for the year was $1,250.00, but it was cold. Summer savings (about?) $420.00. The A/C is kind of unknown because we didn’t use the “old” A/C much. When we did use the A/C We would spend about $150 for electric. With the geo system I was shocked when I got the first bill… it added $20 dollars. The next month I just left it on to see what would happen, that bill jumped up $35.00 bucks. So the A/C seems to work well.

The kW used in winter would be about 5000 kW / month (but it was the coldest winter we’ve had in a long time, I think the news said 1981 but whatever)

We get a off peak electric rate. Normal electric is .083 / kWh summer or winter, off peak is .059 / kWh summer .038 / kWh in the winter. If I use more than 2000kW the rate drops to .023 / kWh. This seems to be a low rate compared to the rest of the country.

I will say in the winter it is on ALL the time. Other details that I didn’t think of is the fan/air noise can drive you crazy because its always on. Air noise you say… picky maybe but its true. Keep in mind I had this retrofitted to use my single speed furnace.

The other thing is the air isn’t hot, feels somewhat cool like you just have the fan running. The exiting temp is 88-90 deg. F. Normal from what I read, but kind of cool if your next to a register. Not a big deal just another detail.

But overall very happy with the system.

Mark

by **teetech** » Sun Oct 04, 2009 9:31 am

Sounds like you could benefit from an ECM motor. Is this a 2 stage split? Cause if it is you definitely need an ECM fan motor. This should help your noise and temperature split.

by **mark1745** » Sun Oct 04, 2009 7:16 pm

Teetech:

Hi, yes it is a two stage split. The ECM would be nice but the original contractor who installed the ductwork (when the house was built) did a poor job so the fan is wired for high speed only, winter or summer. This helps air flow to the far away rooms and second floor. If the fan is set at a lower speed the rooms don’t get air. Not the best solution but that was the contractors fix.

Mark

by **Ryan Miller** » Sun Oct 04, 2009 8:14 pm

I recently installed one in my three bedroom house and just havent seen a better way to heat and cool with one packaged unit. I put a watthour meter on my geo heat pump and figure it is costing me under a dollar a day, and I live in Idaho where it goes from 100+ to -20. I probably installed my D.I.Y. unit for under $7000.

by **teetech** » Tue Oct 06, 2009 5:09 am

Hi, yes it is a two stage split. The ECM would be nice but the original contractor who installed the ductwork (when the house was built) did a poor job so the fan is wired for high speed only, winter or summer. This helps air flow to the far away rooms and second floor. If the fan is set at a lower speed the rooms don’t get air. Not the best solution but that was the contractors fix.

Now we know why you have noise issues and low supply temps. On first stage you need to reduce the fan speed to get the comfort benefits and better dehumidification.

It is a shame that far too often duct work is the root cause of poor comfort and performance of geothermal systems. Not to mention noise issues that come from high air velocities.