Posted By t5800512 on 16 Oct 2013 10:20 PM
Thank you Bill. So how long have you been running on the coated coil? It sounds like WF may have resolved their biggest issue.

My repair history for 2 WF Envision units:

3T unit: Original WaterFurnace 3T unit (with damaged coil) installed 3Q07.

3T unit: Patched coil gave out 4Q08.  Uncoated replacement coil from WF installed.

3T unit: Uncoated replacement coil failed 3Q10.  Another replacement coil supplied by WF installed, this one coated.  Still operating today.

3T unit: power cable to compressor was not installed properly at factory.  Compressor power contacts almost burned up due to intermittent connection.  Compressor power contacts salvaged enough to connect replacement power cable.  So far no further problems.  Don't remember date of problem.

5T unit: (also originally installed 3Q07).  First repair was this year.  Fuse holder for circuit to water pumps burned up on control board.  Control board replaced.

Best regards,

Bill

Posted By Bill Neukranz on 16 Oct 2013 11:52 AM

... I think there's opportunity to use the tstats for retail, small commercial and non-profit structures in a more cost effective manner than using WEL units for the back end analysis, real time monitoring and alarm production.  Plus, it looks like there's some emphasis on internal to the tstat algorithms that take into account weather conditions such that possible energy reduction can occur. 

I'd like to look at all this first hand, so much so that I'm working now to procure 4 of the tstats for a project to gain detailed familiarity.

After I get set up I'll start up a separate thread to share what I learn.

I have two purchased at this point, and am purchasing two more through Ecobee direct.  One should arrive today.  All will go into my house.

I'm going to use the commercial tstats as this 'flavor' has some automation interface capabilities, an expanded alarm set, allows me to demonstrate benefits to businesses and allows me to share here on this forum what the Internet i/f looks like.

So far, I don't see any show stoppers for using these tstats for residential, retail, larger structures, and light commercial settings.  Anything that's up to 2 stages of cooling and/or 4 stages of heating is accommodated, along with dual-fuel setups.  The Internet browser and smart phone interfaces look promising.

There's a claim that if a 'geothermal' versus an 'air source' heat pump setting is used then there are efficiency gains to be had.  I'm trying to find out what the details are.

There's also a claim of increased efficiencies overall due to the included interface to weather forecasts.  I plan to measure this claim over the next 12 months.

Once I have some learnings I'll start a new thread.

Best regards,

Bill

In case you didn't know, there's a fairly active Ecobee user group on Google which is followed by Ecobee.  You'll see responses from the President of the company on down.  They provide great support to the products.  I'm not with Ecobee, just a well satisfied customer. 

https://groups.google.com/forum/#!forum/ecobee-users

I'd like to see an overview of all the ecobee features here in GBT.

Posted By Popoff on 19 Oct 2013 12:20 PM
In case you didn't know, there's a fairly active Ecobee user group on Google which is followed by Ecobee.  You'll see responses from the President of the company on down.  They provide great support to the products.  I'm not with Ecobee, just a well satisfied customer. 

https://groups.google.com/forum/#!forum/ecobee-users

Nope, didn't know.  This is very helpful.  Thanks!

Received in my first of 4 Ecobee tstats today, installed it, got the portal running, and got the smart phone app working.

This is my last post on Ecobee in this thread.  Don't want to take away from current discussion.  See new thread I'm about to start.

Best regards,

Bill

Returning to the question of split vs package - two considerations:

1) Package units achieve high efficiency ratings owing to very short refrigerant paths. However, if selecting a package unit results in just moderately more restrictive ductwork, the theoretical rated efficiency gain is likely to be eaten up by increased blower power to overcome the extra ductwork. One must consider the equipment as an installed system.

2) ECM blower noise is rarely a problem if the ductwork is reasonably sized and installed. Compressors can be quieted by various schemes such as sound jackets, etc. However, the 800 pound gorilla that may show up lies in compressor vibration. Any system whose compressor is mounted / hung from a wooden floor or truss system risks running afoul of harmonic frequencies that can greatly amplify compressor vibration.

So as not to risk client satisfaction, I avoid package units anywhere elevated off a slab.

7-Series principle attraction to me is its ability to ramp down low enough handle 4+ zones, and its non-availability in a split format is a disadvantage.

Hi Curt, thank you for sharing your thoughts on the subject. It is great to have advise from expert experts such as yourself.

Posted By engineer on 19 Oct 2013 11:36 PM
Returning to the question of split vs package - two considerations:

... So as not to risk client satisfaction, I avoid package units anywhere elevated off a slab. ...

In the Dallas area at least you'd have to decide what strategy you'd want to employ for attic located air handler units.  This is quite common, for furnace-A/C and for air-to-air heat pump units.  The furnace gas burners are in the attic along with the A/C or heat pump evap coil, and the A/C or heat pump condenser unit is outside.

Obviously with geo the outside condenser unit goes away.  But because there's rarely a place in a conditioned area suitable to put in the replacement geo package unit, and because of the expense of retrofitting the air distribution duct work to connect somewhere new, almost always the geo package unit gets placed exactly where the furnace/air-handler was.  Which is more often than not (here in this location) in the attic.

It's actually fairly frequent to see furnaces/air-handlers suspended from the roof rafters here.  Thus, replacement doing likewise, with a geo unit, is common.

If there's room in an attic to set the geo package unit on the attic floor joists, then this is done too.  Here's where attention to vibration (due to the compressor) is most critical.

Best regards,

Bill

Thank you Bill.

I'm fine with attic air handlers - I actually like them because they are quieter and typically located near the center of the attic for headroom, and that results in short duct runs. Homeowner keeps a closet. BUT, I insist the attic be sealed and insulated conditioned space, typically using spray foam.

Hanging a package unit from rafters / roof truss upper chords may well handle the vibration transmission issue, but I'd fear to bet on it.

Another major worry for me is having a limitless aquifer connected to plumbing that includes rubber hoses above living quarters, so I'll stick with splits with the compressor sections in ground level utility rooms or garages.

Posted By engineer on 22 Oct 2013 09:14 PM
I'm fine with attic air handlers - I actually like them because they are quieter and typically located near the center of the attic for headroom, and that results in short duct runs. Homeowner keeps a closet. BUT, I insist the attic be sealed and insulated conditioned space, typically using spray foam.

Hanging a package unit from rafters / roof truss upper chords may well handle the vibration transmission issue, but I'd fear to bet on it.

Another major worry for me is having a limitless aquifer connected to plumbing that includes rubber hoses above living quarters, so I'll stick with splits with the compressor sections in ground level utility rooms or garages.

Awfully expensive to insist attic be sealed and insulated conditioned space.  I think you lose some potential prospects due to this insistence.

OTOH, Elden Hampton, a local geo expert here, while he doesn't *insist*, he strongly recommends the same - spend thousands of dollars foaming the attice.

Why not simply use steel duct and wrap with R8 for supply and R6 for return?

One problem with hanging from roof rafters is weight bearing on ceiling and walls, and can causes drywall to crack.  this is what's happened to me.  I am vibration free, though!

No need to put rubber hoses above living quarters.  My HDPE pipe (1") is plumbed direct to the geo packaged units.

Overall, seems for some extra expense the way you're installing in FL. 

Wish  I knew what kind of sensor is reliable for water sensing under the pumps

Best regards,

Bill

Bill there are "wet switches that can shut down equipment and/or activate alarms.

For Curt and I, installing package units in the attic vs splits is high risk/low reward. Yes duct work can be insulated if client ignores strong recommendations. Either way, they pay a premium for attic installs.

Posted By joe.ami on 23 Oct 2013 08:33 AM 
... "wet switches that can shut down equipment and/or activate alarms.

For Curt and I, installing package units in the attic vs splits is high risk/low reward. Yes duct work can be insulated if client ignores strong recommendations. Either way, they pay a premium for attic installs.

Joe, I would appreciate recommendation on wet switches I should consider.  I'm constantly nervous about the water connections at the 3 pumps and 2 packaged units I have in my attic.

Interesting on market differences - have always found this to be a stimulating subject.

In the Dallas area, traditional practice has been it all goes into the attic with HDPE direct to the packaged unit.

Some, like Eldon who does bulk of Dallas area installs, try to insist on changing attic to conditioned space via foaming it, but, it's not an absolute requirement, and at least here in the Dallas area it's a veerrryyyy expensive upgrade.

While generally we don't have conditioned space to put the refrigerant-to-water heat exchanger portion of a split unit, very few have basements, and there's no space in garages (cars are typically out in driveway/street as commonly garages are used for storage because we don't have basements), still, I guess the business paradigm could be changed here to put in split geo units.

Can the refrigerant-to-water heat exchanger portion of the split unit actually go outside, on the same pad as where the conventional A/C, or heatpump condenser was, with HDPE pipe to this outside unit, and with copper refrigerant pipe custom installed from outside to inside attic located air handler unit?  Is this an installation option for the subject at hand in this thread?

Best regards,

Bill

Hey Bill,

From what I have seen, most of the companies that are selling split units sell one for inside (for a garage or closet) and a similar but different unit for outside. The outside system can be set on the same pad as the old condensing unit. I will be setting my new Geo outside unit on an UltraLite pad that looks and feels like concrete, but is really plastic. I will do this so that I can drill holes in it for the water pipes to come up through. On the CM condensing unit, the water pipes come up directly in the split systems metal enclosure. Nice not to have to worry about the lawn mower, weed eater, etc. bumping them. Also, animals will chew through plastic to get to water. I may see if I can get a little grout dropped into the hole where the pipes come up just to discourage rodents and the like from digging under the slab and chewing the pipes.

The existing electrical wires, both high and low voltage, can also be used. The same goes for the copper lines as long as they are flushed properly. That is because the R22 refrigerant oil (from my old system) and R410A oil are not compatible. A flushing agent must be run through the line set along with dry nitrogen in order to get out all of the R22 refrigerant oil.

All things considered, a retrofit using a split unit is pretty straight forward. The new WSHP equipment can go directly in place of the old system. I will be replacing my NG furnace with a variable speed HE carrier air handler (with N coil). This air handler is the same unit I would put in if I were putting in a traditional air to air condensing unit rather than Geo.

I would rather use the ClimateMaster air handler, but I don't have a Carrier part number for it. Anyone happen to know if Carrier sells the CM air handler? I would prefer the CM air handler to the Carrier because the AHRI certifications shows a higher efficiency with the CM air handler. Yep, still concerned about the efficiency thing.

Oh, by the way, my air handler is in a central hall closet. Remember the fuss about me trying to squeeze a combined unit into the closet? I finally gave up on that idea, even though I would have prefered the higher efficiency of the combined unit.

Oh by the way, I was going to ask you about something you said earlier. You said we don't need antifreeze in our area. Is that because you're WF units have a freeze-guard feature? I may be wrong, but I don't think CM has that feature.

I shy from unconditioned attic installs for a couple reasons

1) It is crazy enough that we put the coldest air in the house, the 55*F air expensively cooled by AC, in long thinly insulated (R4, R6, R8, whichever) tubes and boxes in the absolute hottest part of the house...the 130*F+ attic! To compound the sin by adding a leaky air handler with perhaps R2 insulation and a bunch of dodgy penetrations is even more insane.

2) Worse yet, our unconditioned attics are full of the same 75*F dewpoint air that pervades our great outdoors pretty much 24/7 from Memorial to Columbus Day. The aforementioned AHU can't help but sweat, causing about 9 more problems up in the attic.

Maybe Dallas is drier, and few there give a rat's backside about the loss of efficiency, but I won't be a party to a sweaty, moldy, mildewy rusty mess. Theoretically it is possible to build a little drywalled and insulated room in an otherwise unconditioned attic, but that introduces another raft of cost, service access, duct path and poorly installed insulation compromises. I'm just not enough into sales volume to compromise principals to sell a couple more boxes.

It is rare here to encounter a client willing to spring for the $10-15k premium commanded by geo who is NOT willing to also spring for sprayfoam.

I don't lose projects for my unwillingness to install an airhandler in an unconditioned attic. I do lose them over refusal to oversize and unwillingness to be the low bidder on commodity code minimum jobs.

We don't run antifreeze in closed loops because our ground temperature is 70+. WF has freeze protection selectable between 15*F or 30*F; I can't imagine CM is much different.

While it is certainly possible, albeit at a bit of a price premium, to locate the compressor section of a split geo system outdoors, doing so in my AO gives up geo's singular advantage of having no components outside in the weather, subject to the tender mercies of blown sand, airborne salt, pissing dogs, drunken landscapers, and errant vegetation, all of which combine, to various degrees, to greatly shorten the lives of outdoor units.

A garage or utility room location needn't cost precious floor space. It is a simple matter to park the 2x2x2 compressor cube on a sturdy shelf well above ground level.

I'm learning from your installation plan.

My guess is the air handler part of the split geo unit will be smaller than the unit's that currently in your closet.  Thus, another plus of putting in a split geo unit is that you'll have more space in your closet, as I'll bet the air handler part of the split geo system is smaller than your existing furnace.

And I didn't know the condenser for a split geo unit can be purchased in two 'flavors:'  inside the garage, or, outside in the elements.  Yep, the outside in the elements flavor can take advantage of the existing electrical circuit.

Didn't know that an R410A system could use existing copper from an R22 system.  Thought it required new copper.

Overall I'm learning that replacing an old fashioned conventional NG furnace/A-C combination is not difficult with a geo split.

No antifreeze here.  Heating in the Dallas climate is just not fair.  Coldest my EWT gets, ever, is low 60s. 

I do worry about pipes freezing though.  I have the pipes well insulated in the attic.  And where I have a city water connection to my loop I have an incandescent flood lamp aimed at the plumbing for when the attic gets below 32 degrees (doesn't happen often, even if outside temp is in mid to low 20s).

If outside air gets into the teens for a length of time (once every few years) then I'll run the pumps manually kept on, while the geo units cycle on/off automatically per tstat calls.

I have temp sensors outside and in the attic, connected to my WEL energy monitoring system.  I have alarm conditions defined in the WEL system at certain trigger temps.  The WEL system sends me text messages and emails when an alarm is tripped.

Another reason you don't want to use antifreeze: it further degrades the efficiency of your system.

Best regards,

Bill

Curt, much appreciate your comments on market characteristics you have, sharing some of your sales philosophies, and minuses associated with locating the compressor from a geo split system out in the elements.

Many thanks!

Best regards,

Bill

Actually, the new air handler is not as deep or as tall. Neither will help out much with closet space. The added space will be mostly behind the unit which is not easily accessible. It being shorter is good because I can add to the length of the current plenum. That will help smooth out the turbulence of the air flow.

Yes, I have seen that antifreeze lowers the efficiency. That is why I perked up when you said that you did not use antifreeze. I think the WF 7 series has an automatic freeze guard built in. I have not seen any such information on the CM systems. Maybe Joe will know if CM has a freeze guard? Anyway, at 60 degrees, no problem until the system and pumps shut off. I wonder how long it would take the water to freeze. Hopefully the system will cut back on before then. I will have to monitor it to see how it works out. I really don't want to take the risk of turning the pump on manually. What if I'm out of town when a cold snap comes. I will have to look into adding some sort of freeze guard it there is not one build in. Or I can use a low percentage mix of antifreeze. This is one area where I could learn from a local expert.

I'm glad we don't have to worry about salt, sand or sustained high humidity here. I have four condos on South Padre Island (about the same latitude as Miami) and everything there rusts and molds. I get three to five years out of an A/C condensing unit. By then the fins on the coils have crumbled off and the efficiency had dropped to nothing. Then the coil starts to leak and it is time to replace the unit again.

The added cost and other disadvantages of placing a geo split compressor unit outdoors just to take advantage of existing electrical circuit may outweigh the cost of moving the service to the garage.

We routinely reuse copper line sets when converting from R-22 to 410a. We use a very pricey flush solvent to drive out the old oil, but it still saves the typical customer $500 or so in material and labor changing out the line set. We tell them we might have to replace, if the old lines fail pressure and vacuum tests.