Reply to Thread

Found the article.

http://bookstore.ashrae.biz/journal/...2-20111003.pdf

Originally Posted by 19characterusername

There was an article in ashrae journal a few months back comparing boiler tower, boiler chiller, vrf air source, and geothermal for facade dominated (basically residential) building types. Geothermal was slightly better than vrf in some climates, but not by much. Boiler tower heat pump systems were shown to be the dogs they are. The interesting conclusion was that boiler chiller does not make sense for facade dominated buildings due to heating COP of .95 from a condensing boiler vs 2.5 to 3 for an air source machine at design conditions.

Article sounds interesting...

Was the comparison done by operating efficiency, or by investment vs payback?

And could you post a rough idea of the climates geo works better and not good in... THX.

There was an article in ashrae journal a few months back comparing boiler tower, boiler chiller, vrf air source, and geothermal for facade dominated (basically residential) building types. Geothermal was slightly better than vrf in some climates, but not by much. Boiler tower heat pump systems were shown to be the dogs they are. The interesting conclusion was that boiler chiller does not make sense for facade dominated buildings due to heating COP of .95 from a condensing boiler vs 2.5 to 3 for an air source machine at design conditions.

Thanks

I haven't been on in a while, thanks for all the kind posts in agreement. I still have no savings proof on vrv, there is supposed to be a whole floor of vrv and a floor of geo in the new ASHRAE building in the DC area with the sole purpose of proving the savings, and yet we see nothing. I don't have to see geo savings I see my customers on the street stopping to tell me how comfotable they are first then they tell me about their utility savings. There is a down side..... If put in right the routine service is minimal so make sure you have a backup plan for less service if you do more geo!

Originally Posted by mo geo man

I went to class to learn what we needed to know to bid a local project, the equipment cost was more than the engineers buget for the entire mechanical part of the contract. On original bid only one vendor could supply numbers. I like the theory and am excited that it may be coming to geo. But it doesn,t have a proven trac record, we have no data to truley compare it to geo. Oh did anyone forget our country is in turmoil and Daiken or Sanyo are both made in JAPAN!!!

Very , very expensive, just wait, some other Japanese company will come out with another version then the price will plummet.

Better than geo, i think not, every ah has to have its own liq/suct line, electric and drain. Plus to repair them, ya rip them off the wall and replace them.

When they are a third of their price and actually worth the money i may consider it.
I also believe they are everything thats wrong with our trade, plastic, junk that maint people will work on instead of installing a real piece of equipment.

Originally Posted by gillianreynolds

You are right,

I agree with you.

Thanks
oostende hotels near train station

Originally Posted by mo geo man

I went to class to learn what we needed to know to bid a local project, the equipment cost was more than the engineers buget for the entire mechanical part of the contract. On original bid only one vendor could supply numbers. I like the theory and am excited that it may be coming to geo. But it doesn,t have a proven trac record, we have no data to truley compare it to geo. Oh did anyone forget our country is in turmoil and Daiken or Sanyo are both made in JAPAN!!!

You are right,

I agree with you.

I was IGSHP certified and put in one loop and strained my shoulder badly sealing well holes with Bentonite and fusing joints. I spent time recooping with visits to the doctor. I didn't enjoy the mud to much either. I have also put in Daikin systems. From an installation point of view instead of efficiency, I like the air to air VRV systems. I have also serviced both extensively. Daikin is much more specialized.

Steve, I have left the rest of the posts here, your first post has been edited. Please remember that unless you purchase an ad, you can't advertise, which is what your fist post essentially was.

Originally Posted by Steve Cornish

The latest technology Variable Refrigerant Volume systems have many advantages over Geothermal heat pumps. VRV is also a heat pump system that uses energy recovery to provide the highest energy efficiency on the market. The advantages of VRV are:

1. Highest energy efficiency on the market.
2. Low installation cost. No wells to drill. Very easy to install.
3. Low maintenance cost. No pumping equipment to maintain.
4. Operates below 0 degrees F in the heating mode.
5. The system requires no special training for maintenance. Any trained HVAC technician can maintain the system.
6. The room units are extremely quiet.

If you want to know more check out Daikin's website at [url]Daikin is the number two manufacturer of HVAC equipment in the world. They are the parent company of McQuay International.

Steve;

I have some questions about using the vrv-w series for a large project. Could you PM me or respond to this thread? Thanks.

operating cost

All very good arguments and I agree they are apples and oranges, loads and insulation are key. Utility costs are the biggest factor in payback. I guess what I have been trying to compare is the vrv cost to produce 100,000 BTU. We use this as our benchmark when comparing gas, oil, air source, dual fuel and geo so when a customer askes it is black and white to produce 100,000 BTU for 1 hour ( a therm ) it costs x.

Originally Posted by Steve Cornish

The primary issue in discussing GEO versus VRV is that the same or better efficiencies can be acheived with air cooled condensers thus eliminating the upfront and maintenance cost associated with Geothermal. ...

It then becomes a return on investment question.

Guess I'll try explaining this another way.

Clearly there are variables of home tightness and insulation effectiveness, alternative energy sources and cost, and scale that all come into play. Generally the two largest factors determining Geo's return on incremental investment are:

1. heating and cooling load (house size - geo has a fair base capital investment that a small house is unlikely to overcome)
2. alternative energy source cost (Nat Gas = looong payback no matter what size house)

Still, the argument should not be geo vs vrv because they are not apples to apples. Geo can utilize vrv so it is really a nonsensical argument. The type of compressor or "refrigerant" technology should be the same in both technologies in order to get an accurate measure of the incremental cost/benefit of going to ground.

The analysis is geo vs air source. Vrv may be the best current technology, the efficiency of which makes the added capital of the geo argument harder to make.

GEO vs VRV

The primary issue in discussing GEO versus VRV is that the same or better efficiencies can be acheived with air cooled condensers thus eliminating the upfront and maintenance cost associated with Geothermal. Daikin does have VRV systems that are working with geothermal condensing systems. The efficiencies of this system are very high. It then becomes a return on investment question. With standard WSHP versus geothermal there is enough of an energy savings to justify the additional cost of installing and maintaining a geothermal system. Can the cost of adding geothermal to a VRV system be justified? That all depends on the geographical location, the installation cost, and the energy cost. If you have low energy cost like we do in the St. Louis area $0.07/kwh it becomes more difficult to justify the cost differential. Other areas like California at $0.22/kwh would be easier to justify. Also using cooling ponds instead of wells will lower the cost. Also some customers want the most energy efficient product available and are willing to pay more for the system to reduce their impact on the environment.

Is'nt Comparing to geo missing the point? Apples and oranges.

Vrv efficiency is due to variable speed dc motors. Moving the heat THROUGH the system efficiently, not the absorption/transfer efficiency.

Given all else equal its easier to pull heat fro 40f than 0f. So if applied to geo, vrv would make Geo technology even more efficient also!

Well said.
Some GEO manufacturers are working with VRV and I suspect you'll see one in the next 1 - 2 years.

Originally Posted by mo geo man

Steve,
I appreciate the info and am very familiar with your company. My only contention is that evey time vrv is discussed verses geo it is said to be more efficent but no one can provide data to back up that claim.

Always appreciate good dialog on this site!!!

Isnt Comparing to geo missing the point? Apples and oranges.

Vrv efficiency is due to variable speed dc motors. Moving the heat THROUGH the system efficiently, not the absorption/transfer efficiency.

Given all else equal its easier to pull heat fro 40f than 0f. So if applied to geo, vrv would make Geo technology even more efficient also!

Thanks

Steve,
I appreciate the info and am very familiar with your company. My only contention is that evey time vrv is discussed verses geo it is said to be more efficent but no one can provide data to back up that claim. The particular job I have to reference, the decision makers had the engineering firm try to defend thier vrv system vs. geo and the engineer didn't even understand geo, the types of drilling practices, or the specific site conditions. Like I originally said I understand vrv and I think it has great potential. I will be more excited when it can be produced in america. The sad truth is Hvac is one maufacturing industry that is stiil mainly produced here, they are just using less and less american parts.

Always appreciate good dialog on this site!!!

Quaternity

Since it is targeted at residential I am not real familiiar with the unit. It is a heat pump ductless split system that allows for humidity and temperature control. The unit uses hot gas reheat to raise the temperature off the dx coil which allows it to reduce the leaving air temperature off the coil and take more moisture out. Below is a link to their brochure on the units.

http://www.daikinac.com/residential/...-%20Daikin.pdf

Steve, what exactly is the quaternity system?

mr geo man

Since you are from New Haven you may be interested in attending one of our training sessions. We offer installation and job costing training for contractors on a regular basis. We will soon be the Midwest training center for Daikin. We are Thermal Mechanics in Chesterfield, MO. If you are interested send me an email at [email or call at 636-532-1110.

Cost and USA

The cost of a VRV system in very dependent on the engineers knowledge of laying out the system. We work on a daily basis with the mechanical engineers to layout systems so they are both energy efficient and cost effective. We were a major supplier of water source heat pumps in St. Louis. The VRV system has effectively reduced our sales of WSHP to around ten percent. (I am right now putting together a WSHP submittal for a nursing home. This is one of a few we will do this year.) Last year we sold of $4 million in VRV systems in the St. Louis area. We have many different types of projects up and running.

It is true that the VRV systems are currently made overseas. This is due to the history of the product. This system has been in use for over a decade in Europe, the Middle East, and Asia. Just within the last couple of years has the product been marketed in North America. Therefore there was no need to have manufacturing in the US. This is changing. Daikin has purchase McQuay International. They have built a multi-million dollar research facility in the US to develop all of McQuay and Daikin lines into the top products on the market. As sales continue to grow expontially, Daikin will soon be able to justify manufacturing facilities in North America. Daikin is truely a multinational corporation. Last year Daikin's sales were 14.2 billion dollars. For Reference Carrier sales in 2008 were 14.9 billion.