Geo Horizontal Loop Sizing and gereral ?s

[cgrieger]

I am in the process of reviewing bids for a new home which I am constructing this summer and would appreciate some advice.

The Bid which I am leaning towards is for a Geo System and reads as follows
"Install Versatec WaterFurnance (VXV048111). It is a 4 Ton unit with a single capacity compressor with an ECM blower motor and a hot water generator.

Install one 400 foot horizontal ground loop in the yard. This includes the following:
**One 400 foot Traditional 6 pipe horizontal closed earth loop with tracer wire for future locating.
**Mount Pump kits.
** Core drill Penetrations."

You get the Drift.

Here are my question How large of a horizontal Loop do you typically install with a 4 ton system??? This seems kind of small from the reading I have done.

I have another option in the same Proposal detailing the Same Ground loop layout and tonage but it is specified with an Envision WaterFurnace (NDV048111) without me discusing Prices could someone please help me understand what benefit I would gain by paying for this upgrade?

Both Quotes include "Non-Programable Thermostats" is there a reason that you would go non programable are programables not a good Idea with a geo System.

The Company that provided the Bid to me is a "WaterFurnace GeoPro Master Dealer" which I hope means they know what they are doing but don't want to wind up paying a lot of extra money for somthing that in undersized and won't save me any energy usage. I requested a Quote from a Climatemaster Dealer in the area and he told me I would need a vertical Loop based on the size of my property and asked me if he should stop preparing the bid when he hit double what this Water Furnance bid is.

Thank you in advance for any advice you can provide.

Corey

[dan sw fl]

The Bid which I am leaning towards is for a Geo System and reads as follows
"Install Versatec WaterFurnance (VXV048111). It is a 4 Ton unit with a single capacity compressor with an ECM blower motor and a hot water generator.

Install one 400 foot horizontal ground loop in the yard. This includes the following:
**One 400 foot Traditional 6 pipe horizontal closed earth loop with tracer wire for future locating.
**Mount Pump kits.
** Core drill Penetrations."

You get the Drift.

Here are my question How large of a horizontal Loop do you typically install with a 4 ton system??? This seems kind of small from the reading I have done.

I have another option in the same Proposal detailing the Same Ground loop layout and tonage but it is specified with an Envision WaterFurnace (NDV048111) without me discusing Prices could someone please help me understand what benefit I would gain by paying for this upgrade?

The Company that provided the Bid to me is a "WaterFurnace GeoPro Master Dealer" which I hope means they know what they are doing but don't want to wind up paying a lot of extra money for somthing that in undersized and won't save me any energy usage.

I requested a Quote from a Climatemaster Dealer in the area and he told me I would need a vertical Loop based on the size of my property and asked me if he should stop preparing the bid when he hit double what this Water Furnace bid is.


Water Furnace bid is obviously low due to small loop sizing.

http://neogeothermal.com/geothermal-heat-pump-prices.php

Moreover, it is quite curious to me,
How would the Climatemaster repr know what your specific bid is from the Water Furnace dealer?

Check with the local ClimateMaster distributor or corporate office for a more professional rep/ mechanical contractor.

http://www.climatemaster.com/index/res_locator

ClimateMaster, Inc. 7300 SW 44th St. Oklahoma City, OK 73179 USA
+1-405-745-6000

[cgrieger]

"How would the Climatemaster repr know what your specific bid is from the Water Furnace dealer? "

They did not they called me and explained that I would have to go with a Verticle loop and the cost was at xxxx dollars and if I wanted him to continue preparing the Bid. I knew said amount was twice as large as my waterfurnace quote and told him could stop because I was not planning on paying 4 times what a conventional High Ef Natural Gas Furnace would cost me. I was prepared for Double not 4 times as much. The Water Furnace Bid is about 1.75 times as much as several Conventional system bids I have received.

Thanks for the advise I looked at both Waterfurnace's Locator and Climatemaster and found their dealers within 50 Miles of me and and those are the 2 Contractors I asked for GHP bids.

I am planning on calling the contactor today for further clearification about the loop. How large per Ton is a typical Horizontal Ground Loop? Does the 6 pipe statment make a diference? You probably need more details to provide this type of feedback. let me know what they might be and I will call and ask.

Thanks again,
Corey

[teeball57]

First off the waterfurnace versatec does not come with an ECM motor.
The EER and COP on the envision are much higher than versatec.
To determine the loop size you need to do a load on the house.
A heat pump is not a good system to use programable Tstat.

[cgrieger]

Now that you mention it I recall reading that the Versatec is PSC not ECM. The Bid looks like a form letter with a few things edited. (makes Sense why type similar details 2 times) I am assuming that is a Typo the dealer gave me a trees worth of phamplets with the specs for each unit. Only a few things on the Envision Bid and the Versatec Bid are different (Model Number, Single Capacity vs dual Capacity, Warrenty 5 vs 10 year, 17 Main foor and 8 basement supplies vs 14 Main floor supplies and 8 Basement supplies.)


Thank you again for your response,
Corey

[a0128958]

... I have another option in the same Proposal detailing the Same Ground loop layout and tonage but it is specified with an Envision WaterFurnace (NDV048111) ...

I have 2 WF Envision units, just installed last year, with a vertical wells ground loop system as my property wasn't large enough for a horizontal loop installation. I'll be happy to comment to any questions you may have.

Also, I found it worked well to first work with the WF territory manager to find a qualified installer - you may want to do the same.

Best regards,

Bill

[arc8]

Here are my question How large of a horizontal Loop do you typically install with a 4 ton system??? This seems kind of small from the reading I have done.

About 1200' !


I have another option in the same Proposal detailing the Same Ground loop layout and tonage but it is specified with an Envision WaterFurnace (NDV048111) without me discusing Prices could someone please help me understand what benefit I would gain by paying for this upgrade?

More energy eff!!


Both Quotes include "Non-Programable Thermostats" is there a reason that you would go non programable are programables not a good Idea with a geo System.

Not really, it depends on a few things!


The Company that provided the Bid to me is a "WaterFurnace GeoPro Master Dealer" which I hope means they know what they are doing but don't want to wind up paying a lot of extra money for somthing that in undersized and won't save me any energy usage. I requested a Quote from a Climatemaster Dealer in the area and he told me I would need a vertical Loop based on the size of my property and asked me if he should stop preparing the bid when he hit double what this Water Furnance bid is.

Interesting!

[cgrieger]

I left a message for the Contractor that provided the Bid this AM to ask for Clerification of a few things. Obviously ,I need to get the Loop Cleared up as to sizing if nothing else for my own sanity. The Envision Model Listed NDV048111 was stated as Dual Capacity and looking in the literature they provided It looks to me like the "048" is Single Speed wheras the "049" would be dual capacity so I am confused.

I am not sure if the Specification of "Traditional 6 Pipe horizontal" makes a difference. Is it normal to have 6 pipes in a horizontal loop? I have no experience with GHPs and have never seen one installed so this is purely Hypothectical. If a Horizontal loop typically has 2 pipes and they are making the Trench wider (a lot wider I would Guess) with 6 pipes make the 400' Trench 6 pipe loop = a 1200' 2 pipe loop.

All of the Conventional furnaces I have been Quoted have been around 80,000 BTU and this Contractors conventional system he bid was an 80,000 BTU system this at least leads me to think that the calculations are accurate.

Thank you to all for all your help,

Corey

[tecman]

Only as a guideline you need 500'/ton for a horiz loop. Multiple pipes in a trench will increase that by 10-20% more. You mentioned 6 pipes in the trench and 4 tons is about 2400', with 6 pipes is about 400' of trench. This is a rough guideline. Depth, soil type, type of antifreeze, loading and other factors can increase that by 50% in a worst case. Another thing to watch is that trenches need to be a minimum of 15-20' apart if they are serpentined.

The last thing you want is to go cheapo on the piping and have it not work.

paul

[a0128958]

... The Envision Model Listed NDV048111 was stated as Dual Capacity and looking in the literature they provided It looks to me like the "048" is Single Speed wheras the "049" would be dual capacity so I am confused. ...


NSx048 is a 4-ton single speed unit. NDx049 is a 4-ton dual capacity unit. The 'x' denotes vertical or horizontal cabinet orientation.

I don't think an NDx048 model exists.

The '111' denotes 230 VAC, DeSuperHeater included, and ECM fan. A '110' would be a PSC fan.

I don't know if you can get an ECM fan with a 4-ton single speed unit.

My guess is the quote simply made an error with the 48 versus 49 number, and thus the model number quoted should have been NDx049A111, as this would apply to a Dual Capacity unit, with ECM fan motor, and with hot water generating (DSH) capability.

I have the dual capacity units just above (5 ton) and below (3 ton) the 049.

Hope this helps.

Best regards,

Bill

[cgrieger]

"Only as a guideline you need 500'/ton for a horiz loop. Multiple pipes in a trench will increase that by 10-20% more. You mentioned 6 pipes in the trench and 4 tons is about 2400', with 6 pipes is about 400' of trench. This is a rough guideline. Another thing to watch is that trenches need to be a minimum of 15-20' apart if they are serpentined. "

I think what you are saying is that a 400' Trench with 6 pipes would work similarly to a standard 2000' Trench [500'*4=2000' (500*1.2)*4=2400'/6=400']If I misinterpreted please clearify. A rough Guideline is all I needed I just wanted to make sure this was feasable since the Climatemaster installer in the area said that a Horizontal loop was not possible.

The only question left that I need to understand is how wide the trench will be. If each pipe needs to be 15' apart that would make the trench approx 75' wide by 400' long if that is the case I don't think I have room. If all six can reside in the same trench and Legs olny have to be 15' apart I will be Ok becase I have about 240 * 50 Area this could be located in what will be my back yard. so say 10' wide trench 200' long a 15' Bend and nother 185 - 200' could work.

I definetly don't want to go cheap on the Pipe and wind up wth something that does not work that is why I am seeking advise. Obviously if I can use Horizontal as this Contractor states it would be significantly cheaper. I would rather just go with a Conventional System instead of a GHP that does not work properly. I have read horror stories about people getting a poorly designed/installed system and it either not being able to keep the house cool or Utilizing Resistance Heat and negating the benefits of Geothermal.

I am still waiting on a response from the Contractor, they said the Estimator was in the field when I left a message this AM so I am not sure if I will hear anything today or not.

As my previous Post stated there are a few things that are incorrect in the Bid anyway that need fixed (Model Numbers/feature Combos)


Thank you,

Corey

[tecman]

Your math is correct, but remember this is only a guideline. As for spacing, the distance I mentioned was between trenches. If you have multiple pipes in a trench, there are several options. You want to keep spacing at least 2'. You could have a 10' wide trench with 6 pipes 2'
apart. More common is to have a 2' trench with 2 pipes, 2' of fill and 2 more pipes, and another 2' of fill and the last 2 pipes. The problem is that the pipes will be in a 4' vertical fill, and the top pipes will be too close to the surface unless you dig 9-10 feet. I have done 4 pipes with a 7' trench, so the upper pipes are still 5' down. Personally I would not do 6 pipes in a trench. 4 pipes in a 600+' trench is a solution, but with 6 the loss of capacity can be a issue. Soil has relatively poor heat transfer, so with 6 pipes the temps in the loop will likely vary more than you want and reduce efficiency. If your lot is not that big, going with vertical bore holes is the way to go. Costs more but better efficiency on a smaller lot.

paul

[cgrieger]

Thank you.

[dan sw fl]

I am in the process of reviewing bids for a new home which I am constructing this summer and would appreciate some advice.

**One 400 foot Traditional 6 pipe horizontal closed earth loop with tracer wire for future locating.

Thank you in advance for any advice you can provide. Corey

So, Where is the Load Calc in this process?

[alyons00]

Would this design be adequate for a 4-ton unit & 4 pipe install? Generally speaking of couse:

3 trenches 6' deep x 250' long x 2' wide
2 pipes in the bottom of the first 2 trenches 2' apart(this would be outgoing circulation)
Then all four pipes returning in the final trench with 2 of them at 6' deep and the others at approx 4' deep

Is that enough in general? Or am I too short? That would be 500' for each ton.

Thanks in advance and thanks to the OP for a useful thread.

[geodude]

for loop questions goto www.igshpa.okstate.edu use an installer who is igshpa trained and certified.

[alyons00]

Thanks but that site doesn't answer my questions and I don't think there is an installer in my area that I can and/or will trust at this point.

[rkervin1]

reading about your loop sizes, i have heavy clay soil, 2 trenches, 2 foot wide, 5 foot deep, 350 foot long with 6, .3/4 dia. pipe in each trench, 6 ton unit e series waterfurnace, 34/37 degree water temp in lines. 2nd year in new house, 6" walls nuwool insl. electric elements are on a majority of cold weather, (november, december, jan.) HIGH heat bills. Does this loop seem correct to you? thanks in advance,

[heatpumpguru]

Ask the WATER FURNACE Guy for a GIZMO print out,he should give it to you it should give you alot of neat info.Where do you live?We try to keep back up on for around 200 hours a year here or less in PA.

[motoguy128]

So, Where is the Load Calc in this process?

I agree... if you're tight on space in the back yard for an ideal set-up and making compromises, perhaps the load caculations and design temperatures should be verified.

[rkervin1]

we are on 18 acres, in bowling green ohio, should the loop be redone?

[Foleymech]

something is not right. Seems like you have plenty of trench. Someone needs to do a water side analysis to see if you are getting proper flows. And using both trenches.

[beenthere]

Moved to Residential Geo Thermal forum.

[mgould2]

I think you have problems with it. Your temps are too low.

[thermofridge]

Does anyone use the slinky pipe system? Ive installed probably 20 systems using slinky and never was short of loop. Typically, I would use 800 feet per ton. This system works great in confined spaces but about 20% more pipe is needed because of the proximity of the loops. I still maintain 20 feet minimum between loops but the loops are more compact. Trenches are typically 150-200 feet long and hold 800 feet of pipe. The wider the trench the better. I had the excavator put on his 48" bucket for one job. It worked well.

[jpb2]

There is virtually no way to oversize a loop

[ffreeb]

I searched a long time to find this info when I was installing my loops. I know it's from Tennessee but if you look there is a chart of ground temps for the whole US and the loop length chart uses ground temp. I used it for loops in upstate NY.
Frank

http://www.geokiss.com/res-design/GSHPDesignRec2.pdf

[drsmith012]

Get the Envision and get the progamable stat but don't program setbacks unless you want to do so for comfort reasons. setbacks will not save you money. The programables have more "smarts" built into them. better anticapation, learning ect.

I have an Envision NDV038 with a horizontal loop. 3' wide trench x 300' long and six 3/4" pipes (three parallel loops). Three on the bottom and three on the top. But my loop is burried in near swamp conditions.

A good resource is:
http://www.geo4va.vt.edu/A2/A2.htm

Go to the "ground loop" link and then scroll down to figure 21.

[alex_in_fl]

The more pipe you put in the same trench the less efficient they become. Same for stacking the pipes in a trench.

Example: Four ton system. Cooling load dominated. Assume 400 feet per trench = one ton of load.

You dig a 10 foot trench and add 400 feet of coil, cover it with 2 feet of soil and repeat until you have 1,600 feet of coil in the ground. Do you have a 4 ton ground coil?

Answer: NO! Yes, you initially have four tons but not very long ( a few days in the hot summer). The reason is that the soil between the layers begins to heat up. Heat from the bottom coil can escape down and horizontally but not upward (it meats heat from the layer above it). Heat from the next to bottom layer can only move horizonally because heat from the lower pipe is moving up while heat from the pipe above it moves down. Same for the 2nd layer. The top layer has heat moving horizontally and upward but not downward.

Soil type makes a huge difference in ground coil lengths. Spacing needs to be at least 10 feet horizontally with 15 feet being better. Vertical spacing needs to be several feet or you get less efficiency.

Suggestion: Ask for a loop calculation from the guy offering the horizontal system.

Pardon the long post.

[crash11]

Does anyone use the slinky pipe system? Ive installed probably 20 systems using slinky and never was short of loop. Typically, I would use 800 feet per ton. This system works great in confined spaces but about 20% more pipe is needed because of the proximity of the loops. I still maintain 20 feet minimum between loops but the loops are more compact. Trenches are typically 150-200 feet long and hold 800 feet of pipe. The wider the trench the better. I had the excavator put on his 48" bucket for one job. It worked well.

I did a slinky for mine. The only difference is I didn't do trenches because I'm on pure sand (nothing but cave-ins). So I just dug out an area 30' by 90' at 7' deep. I spread 3000' (4 ton system) of pipe throughout the entire area and spaced it evenly as best I could. The slinky method definitely has it's place in certain applications (such as mine). If you are on ground that is trenchable I'd just do straight lines though. I will say this, it was nice not having to deal with straightening out a ton of coils. I just drug them from one side of the hole to the other.

[crash11]

reading about your loop sizes, i have heavy clay soil, 2 trenches, 2 foot wide, 5 foot deep, 350 foot long with 6, .3/4 dia. pipe in each trench, 6 ton unit e series waterfurnace, 34/37 degree water temp in lines. 2nd year in new house, 6" walls nuwool insl. electric elements are on a majority of cold weather, (november, december, jan.) HIGH heat bills. Does this loop seem correct to you? thanks in advance,

You should be getting better EWT's than that, but it's because your pipe is so shallow. Sounds like you roughly have enough pipe (as far as length) buried though. You just have to get it deeper if at all possible.

[Josh Martin]

were can I buy a water furnace system I would like to have one but every one I talk to wants to install it too

[geodude]

were can I buy a water furnace system I would like to have one but every one I talk to wants to install it too

Unless you are a certified Waterfurnace dealer or installer you can't. Its not worth the hassel and as a dealer I would not sell you a DIY unit. Its for your own peace of mind and safety;)

[beenthere]

were can I buy a water furnace system I would like to have one but every one I talk to wants to install it too


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[PHDHVAC]

I will be the first to acknowledge that my level of expertise is very lacking in this area however I have aquired a 5 ton tube in tube and have 5 acres of land lots of clay, ground water temperature 58 degrees even in hot summertime (oklahoma) water comes from the gerber wellington aquifer 360 ft deep and is neutral ph and soft. I have a new York 410 a unit 5 ton pkg straight propane heat and electric cooling but do not know how to go about correctly installing my ground loop to lower condensing temperature. Do I just make a closed loop ? Do I take well water an pump through condenser and re inject? Whats the best way to do it? Any suggestions from people that are in the know about ground loops would greatly be appreciated

[beenthere]

PHDHVAC.

You need to get your post count up to 15, and apply for Pro Membership.

Then you can get more technical answers, in the pro forums.

We have a Pro Tech Geo forum.