<!--[if gte mso 9]> Normal 0 false false false MicrosoftInternetExplorer4 <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} /* List Definitions */ @list l0 {mso-list-id:561211918; mso-list-type:hybrid; mso-list-template-ids:617414542 67698703 67698713 67698715 67698703 67698713 67698715 67698703 67698713 67698715;} @list l0:level1 {mso-level-tab-stop:.5in; mso-level-number-position:left; text-indent:-.25in;} ol {margin-bottom:0in;} ul {margin-bottom:0in;} --> <!--[if gte mso 10]> We are planning on building in east central Tennessee.  While not building in the mountains, the area is heating dependant, but we will also need to install an air conditioner for use during the hottest months of the summer.  The shell of the home (including the slab) will be very tight and well insulated.  There will be an attic, main living floor and possible a basement.

 

We would like to install a geothermal heat pump (GHP) to provide hot water for a radiant floor system in the basement, first floor, garage (partially conditioned) and future attic space. We would like to use the reverse cycle of the GHP to provide chilled water for the air conditioning system.  I was considering using a mini-duct high velocity system to avoid the use of a large trunk duct system.

 

We will also need to install an energy recovery ventilation (ERV) system to remove moisture and provide fresh air.

 

My questions start as follows:

 

<!--[if !supportLists]-->1.                  <!--[endif]-->Is this type set-up even possible?   I have seen SpacePak and Unico systems on the internet, are there other high velocity mini-duct systems available?  Are such systems compatible with GHP brands such as WaterFurnace, Hydron Module, FHP and Econar?

 

2.         Would we also need a separate duct system for the ERV? 

 

3.         How would I go about finding someone with experience to design this type of system?

 

4.         I have also considered throwing a solar hot water system into the mix to provide hot water for the radiant floor system and a separate solar hot water system to supplement domestic use.

 

5.        Regarding the ERV system, are exhaust and return ducts required or recommended in each room (bedrooms, bathrooms, living, dining, kitchen, etc)? Separate exhaust vents are currently specified in each bathroom and in the kitchen.

 

Any suggestions or recommendations are appreciated. I tried to keep the details to a minimum, but more details can be provided.

High velocity systems are both less efficient and harder to correctly install than conventional duct systems. Their principal use is retrofits where installing conventional ducts would be hugely disruptive.

ERV shouldn't need separate ducts to every room - it works off main system

3) Get local references and track them down

4) Doable, but payback may be long and additional complexity poses both first cost and operational issues

There are systems which make both warm water for heating and cool air for cooling - check out Waterfurnace Synergy models - no need to deal with chilled water, which is far less common in single family houses.

You've come up with several uncommon cutting edge technologies. Finding a contractor knowledgeable in all of them capable of marrying them properly in a single project is likely to pose a huge challenge.

I was preparing a response to say the Synergy system appeared to be very close to what I was looking for. Then I read the “Waterfurnace Synergy 3D” discussion and am now not so sure. The installer that I have been talking with in Tennessee is a WaterFurnace GeoPro Master Installer, not real sure what that means. The company has been around for some time and does mostly commercial/institutional systems, but has a residential branch. They claim over 40 years in the business and have been very helpful. It was interesting to learn that the warranties are between the manufacturer and the installed and not the end user.

Several years ago I had been looking at Hydron Module, but they had no local dealers at my present location. There are several dealers in the area we plan to relocate. Looking at their website, it appears that they may have relocated from Mitchell, SD. If they have a similar system I may be interested in their product as well.

I guess that in reading any forum, many people that are having problems with their systems like to vent and look for help. I am hoping that there is a large silent majority that have no problems and love their systems.

With all of the potential problems from complexity that that my proposed system appears to have, I have decided to pursue a system that will supply hot water from my radiant system, provide hot domestic water and forced air A/C.

However, I must have a problem with complexity, because I need to ask if multiple cooling coils can be installed from one geo unit. I have three floors (attic, main level and basement). Efficiently ducting such a system could prove difficult.

No geo system that I know of yet offers the refrigerant metering required for multiple cooling coils.

However, several brands of ductless minisplits do offer what you appear to be after - Daikin, Mitsubishi and Fujitsu

They are (or can be) very high efficiency systems, but they are all airsource.

What about a geo-exchange system that does just liquid to water (both hot and cold storage tanks)?  Could one then hook up a ductless output units in distinct zones?  The ductless units I'm currently considering are from Multi-Aqua and cool via a supply of cold water, not refrigerant.  (I think...)

My one concern is how to insulate the cold-water piping to prevent condensation forming?  Insulated PEX?