Discussion in 'Maintenance and Troubleshooting' started by Mudly007, Jan 24, 2011.
Eight tons? Why so much?
re. Why so much
You tell me Bergy? I'm interested in your comments. As mentioned earlier the calculated heatloss on my home with HRV installed is about 68,373. The 5 ton water unit outputs about 51,00 BTUs and although I don't recall the air unit I'm guessing it would output about 30,000. A total of about 80,000; a bit higher then the 68,000 mentioned but I presume there are a few other factors involved.
As I understand from earlier parts of this thread, Mudly007's 4 ton system is serving a home similar to mine and, if I understood correctly, there was some suggestion that his system may be undersized.
As mentioned, I will be interested in any firther comments you may have. Thanks.
check out the zip codes - one in MI, the other in "North Saskatchewan"
Design air and loop temps probably vary a bit between the two.
FYI; the Zip Code, actually we call them Postal Codes in Canada, is S0K 4P0 if that helps you. Thanks
re. Zip Codes
FYI - the postal code for my North Saskatchewan location is S0P 4K0
I understand things are different in Canada, eh?
My use of "zip code" was a literary device to highlight the far northern latitude.
re. Zip Code
It's -27C in Inuvik, North West Territories; that's a far Northern Latitude. It's only -12C where my house is Hope you'r keeping warm down there in Florida although the way things have been going you could be bundling up too. Have a good one.
The best thing we can do for prospective geo users in the far north is send them luggage...help them move south.
Your help is Appreciated
As I said in my very first post, we are a bit nervous about how our new system is going to perform. I told my wife that you could offer some help if we run into problems and she is very appreciative of your offer; and laughing her fool head off. We both appreciate your humour and hope the big snowstorms on the East Coast don't reach Florida. If it ever gets too cold here we can always hop into our rig and join you in Florida. Take care
Fixed is Fixed...
Hello everyone. I figured I would update this post to let everyone know where I ended up. Turns out the system size is correct. My heat loss calc is correct and the geo loop size and compressor size is also correct.
To recap, my problems were too much run time, house not holding set-point, too high energy bills, and lack of comfort in general
Turns out my house not keeping temp was a result of the AUX not being programmed properly from the start. Once this was taken care of the house stays at the setpoint and uses AUX when it cannot hold that set-point in stage 2.
The house felt cold because the thermostat was not reading temp properly. Basically the system thought it was 70 and controlled that temp. The problem was that the actual house temp was 67 and 1-3 degrees colder in outer rooms. I was cold because 67-64 is not what I am looking for to be comfortable. The Waterfurnace thermostat can be programmed with temperature offsets. I offset my system 2 degrees and now my calibrated FLUKE thermometer reads what my thermostat does. Much more comfortable.
Other comfort issues were related to the duct work. I have a lot of it because I used trusses for my basement and all duct work needed to stay in the trusses. The contractor was unable to run big trunk lines because I didn't want bulkheads. This extra duct work necessitated the larger fan motor to get the proper amount of CFM to all parts of my home. The temperature difference from room to room is about 1 degree now and was 1-3F. This was accomplished by tuning of the dampers in the duct work using CFM readings at all registers.
An upgrade that may have kept me from needing the larger fan would have been a zoned system. If my basement was zoned differently from my main floor I would be heating more in the basement which would heat the floors and main floor living areas. This may have helped with the air flow because it would be used more constantly in the basement and not in all the upstairs duct work. There is a good chance I will still do this upgrade to make my fireplace work with the GEO and not against it.
My system design is good. The AUX is now coming on when the temp is in the low teens to single digits which is where it is designed to be used. It only comes on for the period of time necessary to get the house up and then it turns back off using only Stage 2 compressor, once the temp is good it goes to Stage 1 and then off entirely. A BADLY designed system will use AUX a lot and this kind of heat is far from the 1 unit of electricity equals 5 units of heat. Mine is not doing that, if yours is, that is a problem for sure!
My unit does not turn off very often below 30F. The major thing that I learned is that is okay. My house needs the heat! If my compressor is running in stage 1 or 2 it is because the house is loosing heat at the same rate the system is putting it back in the house. The big plus is that the entire time it is running it is creating heat extremely efficiently as compared to forced air systems (it produces 5 units of heat energy for every 1 unit of electricity). If I had a propane furnace I would still need to add the same BTU, it would just cost me more in propane to do it. HERE IS THE THING PEOPLE… it is not free to heat my house just because I have geo. It costs less than other systems. So, instead of spending $300/month to heat I could spend $500. The sooner everyone comes to grips with the fact that geo is not free the sooner people will be happy about it. My house is 4600 sqft… in truth $300 isn’t bad to heat it when the average temp for a month is mid teens to 20.
Bigger is not better. The bigger stuff costs more to install and more to run when it is running. Smaller is a problem because you will use AUX too much so you need a system that is JUST RIGHT… Make sure your contractor knows his stuff. The most important thing to ensure when doing a geothermal system is to MAKE SURE YOUR CONTRACTOR KNOWS HIS STUFF!! And one more thing MAKE SURE YOUR CONTRACTOR KNOWS HIS STUFF…
Geo Heat Problems
it was good to hear that you have your problems solved to your satisfaction without having to make any significant changes.
As you may recall, i am following your thread mostly out of curiosity and the fear that I too may experience problems. My own system will not be up and running until this summer and next winter will be the real test. I have the #1 contractor in the province doing my design and install and am trying to maintain confidence and optimism with this design. The one little drawback to my system is that the geothermal contractor does no do the hydronic heating system or the hot air ducting so I'm not sure how much the overall sucess of the system depends on the hydronic plumber and the tinman.
You talked about replacement BTUs and I get the impression that you are dealing with a somewhat high heatloss; maybe I misinterpreted some of your comments. The way my house is insulated and the system designed for -27°C, my 10,000KW aux. heat is only supposed to run less then 10% of the time on those cold days. In fact, the way one of the independent heat loss guys put it, once the house is up to temperature I should be able to heat it with the lightbulbs and the big screen TV. I think that comment was made a bit tongue-in-cheek but I think the intent is that I should not expect to be experiencing too much heat loss. Between $30K for insulation and almost $50K for heat I sure hope I don't need too much else.
Again thanks for the update. Take care.
glad to hear you are happier with your system.
I too spent a significant amount of money on insulation and designed my home with energy efficiency and low heat loss in mind. I have a thermal camera and I used it often during the construction. I have extreme insulation in my home. R50 attic, R30 walls, R18 Slab, R35 Basement Exterior Walls. I paid a premium for windows, doors, and foundation materials. I built my stud corners to maximize insulation.
I am running a 4 ton system and heating 4600 sqft with it. I would say that’s not bad.
After my insulation was done and before drywall, my contractor came though and told me I can heat my home with a candle… I figured “man, this geo is going to be cheap!” Why do they do that stuff? When it wasn’t my version of “cheap” I was angry and unsatisfied and gunnin for blood.
Again, people need to have a realistic expectation for what a geothermal system can do. The installation contractor can go a long way to instill that. A geothermal system will produce heat at a given rate by converting 1 unit of energy into 5 units of heat as long as it is running. And when my 4 ton system is running in Stage 1 it costs me $0.37/hr, in Stage 2 it costs me $0.45/hr and when Auxiliary is on it costs me $1.07/hr at $0.125/KWH. Those are the facts. How often it runs is related to my building envelope, which is tight, so it is more related to how cold it is outside. When it’s really cold, its really expensive, when it’s warm its inexpensive.
Installers should not sensationalize the capabilities or they are shooting themselves in the foot by ensuring their customers will not be happy because the results are not what they say. My contractor was captain BS when it came to telling me how awesome geo was going to be.
Here it is: It works, it is more efficient that gas, it is better for the environment, and it “CAN” be cheaper. How much cheaper, well that depends on a lot of variables, like cost of propane, cost of natural gas, cost of electricity and ground temperature. Hey, at least there is a tax credit in the US so I get 8K back. Makes the payback a lot easier to swallow!
Hang in there and keep the faith… make sure the workmanship warranty is there!!
Thank You Forum for all of your help and guidance. This is a great tool! I have not done cooling with geo yet so I am hoping I don’t have another issue when I get to that stage! My guy says "IT'S WAY CHEAPER THAN HEATING” lets hope I don’t have unrealistic expectations again…
I am working on zoning this system to fix the issues that I have when I use my woodstove in the winter. When I am having a fire to heat the main floor the lower floor gets too cold because the only thermostat is located near the fireplace. When the fire goes out the Geo kicks into AUX because the heat loss in the basement was not maintained. My HVAC contractor didn't do me any favors as there is no easy way to split up my system without putting a damper on every singe heating register duct in the home. I am considering an ARZEL heat pump pro system because I have 26 round ducts to damper and eventually I am going to drywall my ceiling. I hear the Arzel dampers are very low maintenance with very little that can go wrong at the damper, meaning less likely to tear apart drywall because of a problem. Anybody have experience with ARZEL, the dampers, or the heat pump pro setup?
Also, what can I count on for run time in the summer? I would assume it is much less than heat run time in the winter?
I highly recommend Arzel
I have been using them since they started here in Cleveland. I only have one heat pump pro in service to date, but I have not looked at it since it was installed better than two years ago. The best thing about Arzel is the ability to zone a system without changing the sheet metal.
There are "tricks to zoning" that can greatly reduce your outlay for product. One used to be able to buy direct from Arzel and they had well trained CSR to aid in design. I know the people are still there, but one now needs to deal through a supply house. They some times make an exception for me.
I have the heat pump pro programing soft wear on a flash drive in my pocket as well as several wiring updates I helped with how to use this system with geo units. Let me know if I can help. (Could buy Joe Hardin a beer and stop by and see the guys at Heat Controller on the way.).
I do not normally heat homes with candles, they cause indoor air pollution that can be deadly, nor promise it can be done. I do not use zoning to save energy, but it could very well do your situation some good. If the system is set up correctly we should be able to keep the evil aux heat off and get it to run in stage one most of the time, while ignoring the heat from the wood burner. We can have 4 zones and two slave zone with the Heat Pump Pro.
Talk with me before you write any checks. BTW it is not 2016 and the zoning system becomes part of the geo install tax credit.
Mark, I'll take that beer. Be a shorter drive for you to meet us in Swanton OH when we do my Bro-in-law's place.
Glad to hear you have some experience. The thing that concerns me about the HPP is the fact that it takes over control of the geo unit based on LAT. In my understanding the LAT on a Geo system doesn’t change much within a specific stage. For instance, my geo runs 82F LAT in Stage 1, 88F LAT in Stage 2 and around 118 LAT in Full Aux. Heating. The factory defaults on the HPP are set to control at much higher LAT temps.
The contractor increased the HP of the fan motor from ½HP to 1HP to create higher CFM. Currently my dip switches are set to create 1600CFM in LOW, 1700CFM in MID, and 1850CFM in HIGH. The system was originally running at 1050, 1350, 1550 CFM respectively. Correct me if I am wrong but I believe the operating principals dictate the fan to run in low speed when the geo is in fan only or stage 1, MID speed in Stage 2, and HIGH speed in Stage 2 plus AUX. At the original CFM set points with no zoning air movement could not easily be perceived at many of the registers which is what spurred the 1HP Fan upgrade.
I am assuming that with zoning I can theoretically lower my CFM with the dip switches because I won’t be conditioning my entire 26 registers at one time as I was before. Lower CFM should give me higher LAT conditioning less space so should produce a shorter run time. I plan to zone 3 splitting my upstairs in 2 zones (bedrooms vs. Living Space) and the basement separate. Of 26 registers I have 10 basement, 10 Living Space, and 6 Bedroom.
Also, do I need to install a modulating bypass damper? Or is this only necessary if air flow sound is not acceptable?
What are your opinions on my CFM vs. LAT numbers?
We can make the HPP do what ever you want. I like LAT response because it saves fuel cost by reacting to temperature and not time. I can get the program from the Arzel guys to change what the HPP looks at for LAT. I have it, but it is on my last, (now dead), lap top.
Once zoned, using your ECM drive blower we can max out the COP and EER of the fan based on the zoning air flow call for heat or cooling. We should be able to do so with out a by pass damper. That is my plan, your mileage may very. Every system is unique.
Your numbers look good, but I like Lobby like to measure.
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