Discussion in 'General Discussions' started by ChicagoWasp, Nov 2, 2016.
What is the driller putting in the holes? HDPE pipe or copper?
I didnt have a loopfield last summer, so i heated my hottub with a 1 ton. It worked great. Defiantly think you should try it, its a two birds one stone senario. Let me know how it turns out.
As far a smart tstats go, I would stay away from the nest, atleast for now. Its not really set up for geo excange. If it senses a heatpump it assumes its an air source and trys locking it out once the outside air is too cold. Plus the idea of turning of the hvac wile your away isnt a good idea for geo eather often the nest will end up using backup or emergency heat (nasty overpriced electric resistance heat) to bring the house back up to temp.
Congrats with your new home/system.
Sounds like an interesting install!
How big are these houses that they require 6 tons and 2 units?
I have a 2600 finished ft^2 two story, with a 1000ft unfinished (for now) basement done with a 3.X ton Carrier GTX unit. I have two zones (basement & 1st, 2nd floor), which is as simple as run the ductwork and add in the motorized dampers that are controlled with a Honeywell zone panel. For smart thermostats I am using two of the Honeywell ZWStat units that are hooked to a Honeywell LYNX alarm panel and a Wink Hub2 setup. In all reality we barely touch the thermostats. The system just runs when it wants and we're happy. Geo (and heat pumps in general) have a slower return time and thus don't like big temp swings. Set it and forgot it IMHO, especially with a COP as high as it gets!
The Waterfurnace Synergy 3D is a versatile unit. It can heat air, cool air, and heat hot water. The issue is it can only do one thing at a time. This is more appropriate for seasonal changeovers based on programmed priorities, not concurrent heating and cooling loads such as AC and pool heating.
Careful load calculations including the pool and control sequences with have to be designed in.
In most cases it would be prudent to have a water to air unit for to satisfy the loads of the house and a separate water to water unit for heating radiant, domestic hot water and pool heat.
Yes loops have been installed under the conditioned space before, there is even one engineer on linkedin that makes a case for the loops somehow benefitting from the heat within the home (SMH).
Generally when someone asks about a design, my questions are upstream of the stated data. Heat loss/gain? Balance point? How did we arrive at size of equipment and loop field.
Location of the field is inconsequential as long as it fits where you want to put it and adequate for the equipment/envelope served.
Split sytem geos with gas back up tend to be less efficient. If nat gas available and emergency heat desired, I'd look to a fireplace or two.
Thanks everyone for all the responses.
I see. Makes sense. Thank you
Your plans sound enthusiastic, but ...... so here are a few thoughts.
1) The synergy 3D has issues when switching over from heating to cooling all the time. The reversing valve will give you trouble down the road, we have been using them largely 7-8 years ago, but moved away from it to either put in a water-water unit for radiant and hot water, and then use air handlers with chilled water from the same unit for a/c. Alternatively, we put in a 5 or 7 series for heating and A/C, and use a dedicated unit for some radiant and domestic hot water. You get more bang for the buck, avoid the synergy 3D having many issues trough frequent switch overs, an can more efficient provide water heating and air cooling at the same time.
2) Heating your pool? Get an air source heat pump. At the end of the heating season, when you start to heat your pool, the air is much warmer then the ground where you just pulled all the heat out all winter long. Plus you don't want to pump your 20,000 gallons of pool water through your basement, if you ever have a pipe burst your basement becomes the new pool. Aqua cal make great and quiet pool heat pumps.
3) Synergy 3D does not come with monitoring since the boards are older versions.
4) 2 small units cost a lot of money, putting in a larger unit does not cost you much more.
5) nothing wrong with drilling under the building, if they use HDPE pipe, heat fuse it and pressure test it.
If this is my house, I would do a water-water 5 ton optiheat unit, put in radiant floors on each floor, and then use 3 small hydronic air (one for each floor) to provide A/C, and use the same water-water to make all of my domestic hot water. Attention must be paid to design the radiant floors to the lowest possible hot water temps, usually not more than 90F, to keep the system run efficient.
If for some reason the house will not be all radiant, I would put in a 7series with zoning, and do domestic hot water and part radiant with a dedicated water-water heat pump.
What you are planning here, you are creating unnecessary trouble down the road, at increased upfront costs.
The other question you need ask yourself is how you control everything?
This come from someone who has a synergy 3d in his own house, has a pool, and does a/c with it. I would not do that again. After putting in a few hundred units each year, I have my scar tissue, and learned not to have heat pumps going from heating to cooling too frequently.
Thank you very much for that feedback. Wow that is super helpful.
One more question on this.
If I go with a series 7 for whole house with zoning and separate water to water unit for radiant basement and pool, will the series 7 be able to properly heat and cool the second floor.
We are looking at 1-2nd floors totaling 3800sq ft. (1800 first floor and 2000 second)
We have a basement of 1400 sq ft finished.
So are you saying that it's best to not use the "Auto" feature on the thermostat?
I have 2 Series 5 units.
Why would you use both heat and cool in one season, I mean yes geo is efficient but you don't need to be an expert to realize that cooling in winter and heating during summer is a wast of money, wear and tare on equitment, and it stands against one of the biggest advantages of geo. Beaning green.
Save your money, save your equitment, save the environment. Besides the little convort you gain form percise temperature you'll lose when your equipment fails premuturly from unnecessary wear.
Just my .02
Sure, what size 7 series heat pump do you pick? 3,4 or 5 ton? And what is your heating and cooling load for 1st and 2nd floor? 3800 sqf stacked over 2 stories at Illinois Energy code. Should not be a problem. Flow calculations are crucial.
Auto feature is good, just have a few degrees deadband, e.g. start heating at 70F and cooling at 75F , not start heating at 71 and start cooling at 72F degrees.
If you have large heating and cooling loads at the same time, or large radiant and forced air zones, the synergy 3D will prioritize on one job, than going to the next one, and pretty quickly going back to the prioritized zone, switching back and forth with one of the reversing valves very frequently.
Same with back and forth between heating and cooling.
Separate names with a comma.