New Zoned System Trouble

[dash]

We need more infromation ,to provide anymore advice/suggestions,on your situation,IMO.

What do you mean by spiking,in minutes or hours?

[carestx]

Dash,

Here is the link to the AirAdvice system installed. Before they changed out the orifice, they said there was no condensation on the coil during first stage. W

ith expansion value humidity does drop when unit cycles but shoots right back up when it shuts down.

It has a 10% spike twice an hour High in the 68-70% range low in the 60-62% range.

Have had all the t-states (3 zones) set to 70 degrees for three days.....freezing us out of the house...

I am trying to figure out how to add a photo of the AirAdvice log. Will post when I figure it out.

Row that starts as 56 is the Low Humidity Mark for the day listed, then Average and High...Temp. is the next three numbers....

Monitor 8686 Particulates Carbon Monoxide Humidity Temperature VOC (ug/m3)
Weekday Low Avg High Low Avg High Low Avg High Low Avg High Low Avg High
10-21 3 14 69 0 0 1 56 62 67 72 75 76 775 1080 1387
10-22 0 11 58 0 0 0 61 65 68 73 74 76 726 1013 1279
10-23 0 15 89 0 0 1 45 61 74 66 74 77 725 1170 2140
10-24 0 7 68 0 0 0 50 56 67 68 70 75 591 745 1007
10-25 0 4 67 0 0 1 55 66 73 68 73 76 634 770 943
10-26 0 6 63 0 0 0 57 67 75 72 74 75 486 704 910
10-27 0 4 52 0 0 1 56 66 74 71 73 76 440 610

[Steve Wiggins]

carestx I wish I were a little closer to you. I am about 2.5 hrs away You keep asking for a consulting company (group) but what you really need is an individual person that actually knows what he is doing.

[carestx]

Steve,

I am trying to remain "neutral" in having the system evaluated. By using a Counsultant or Eng, firm, there is no chance their findings would be self serving. Does that make sense?

[Steve Wiggins]

Well anyway if you want a full report/load calc/design recommendations with pictures I can do that for you. I will post the pics here and then everyone can offer their input. Being far away I have no desire to contract with you to correct the problems so my evaluation would not be self serving.

Does the company that installed the system employ a state license holder and did he pull a city permit that passed a final inspection?

[dash]

Originally posted by dash
They may have the 5 and the 2 ton indoors fans ,running at the same time.

More air flow ,equals less humidity removal,so that could be the problem.

From more input:
1.Post model numbers of all equipment.

2.What size ducts come off the indoor units,supply and return?

3.Return grille sizes ?

4.Pictures would help a lot!!

FYI--This is the strangest setup I've heard of,but doesn't mean it can't work.


One problem is,you are now trying to push 7 tons of air thru a duct system designed for 5 tons.

More information ,like answers to the above questions and others ,is what I was thinking of.

[carestx]

They are state licensed and did pull a permit. It did not pass but the inspector whould not comment on the configuration/design, except state he has never seen anything like it.

It failed for little things lite the drains, duct straps and access to the unit.

The City has not been back out to reinspect.

More then willing to have you out and willing to cover your time if you think you might find something.

Tom Carey
972-612-8843

[carestx]

Dash,

Working on pictures, and will get any and all model #'s I can find. Will do my best on the grill/duct sizes...

TC/Dallas

[dash]

Great thanks.I'm thinking the duct system or there stages and coresponding air flows are the problem.
It would be helpful to know if the air flow ,increases ,as it goes from 1st to 2nd and 2nd to 3rd stage.



You may want to ask them,how, if they designed the duct system properly for 5 tons,is now capable of handling 7 tons?

[carestx]

Here is some of the data ask for:
*
Both labled AMANA
*
5 ton outdoor unit** Model # RSG60C2A**** uses* 410A refrig.*** 16 seer
Indoor unit** Model # CF60FCA
Furance** 95* IIQ* Air Command Furance* GUVA / GCVA*** only wording I could find.
*
2 PVC vents, one high on furance, one low (this looks like one*would be*a fresh air intake?)
*
2 ton outdoor unit** Model # RCE24A2A** Labled AMANA** old refrig.** 14 seer
Indoor* "NOT labled"* Model # ARUF024-00A-1A*** Has energy guide showing "most effecient"
*
Returns and Supplies
*
Zone #1* (Master Bed/Bath, Office, Guest Bath)
*
Supply Total = Five (5) 8x12*, One (1) 6x10
Return Total = Two (2) 10x25* (baseboard/wall)
*
Zone #2 (2nd floor)
*
Supply = Three (3) 8x12* Three (3) 6x10*
Return = Two (2) 20x25* One (1) 10x25* (all baseboard/wall)
*
Zone # 3* (Main home)
*
Supply = Eight (8) 8x12*
Return Three (3) 10x25* (two baseboard, one celing)* Three (3) 16x16 (all baseboard/wall)
*
*
I couldn't get to much of the duct work but I gave it a try, all duct appears to be R6.0 Silver Jacket duct:
*
Return @ units = Two (2) 16"* and Two (2)* 12"
*
They feed the two ton unit from the collector box with One (1) 16"
*
Supply = this is a mess, I saw what looks like One(1) or Two(2)* 16" or larger duct and what looks like maybe*One (1) 12" coming off the units.* One of the 16" or 12" comes off the 2-ton and feeds back into the colletor box?** This is were I can see the dampers installed
*
From there, they run all over the the attic and feed into Fiber Boxes/ Triangles that then branch off into smaller duct, (6" to8" mix) that feed the indivual vents.
*
Misc:* Both units have High Efficeny (Goodman) UV and Electric Filters* / 5 ton has AprilAir Humidifier on supply side of*it
*

[carestx]

http://photos.msn.com/Viewing/Album....aMNH0tFQ%24%24


Cut and paste above link into address bar! 25 some odd photos.........

[Steve Wiggins]

carestx - I think I have figured out at least one of your concerns regarding humidity. You report that when the system runs the humidity goes up, not down. I think you mean to say the "relative" humidity goes up.

Humidity is the amount of water in the air. Relative humidity is the % of water in the air relative to how much it is capable of holding.

So by lowering the temp it changes the ratio and % of water in the air at that temp.

Warm air can hold more moisture than cold air. Think of the heat in your house at 78°F as a big gulp cup. Then think of the heat in your house at 68°F as a coffee cup. Fill the coffee cup with water which represents the moisture in your air. The coffee cup is 100% full or in other words you have 100% realtive humidity. Then pour the water from the coffee cup into the big gulp cup. You have the same amount of water but now the cup is only 20% full or 20% relative humidity. So in this way a warmer house can show a lower percentage. Warming the air is like having a bigger cup because warm air can hold more moisture than cold air.

All this still doesn't forgive the fact that you are uncomfortable. What you need is a removal of moisture without a lowering of temperature. When your humidistats call for reducing moisture the blower in the furnace should slow down and make the coil sweat more. If this isn't happening then we should probably start there to figure out why not.

Looking at the pictures I am very concerned about what happens in worst case scenerio when only one zone is calling. Where is the extra air bypassed? I would like to see a pressure reading in the supply plenum with the smallest zone calling for cooling. Those VS motors can only stand .5 max static pressure and you sure don't want to be replacing those babies every year.

Another concern is accessability. Can a man stand in front of those double stacked monstors and reach the upper unit to effectively work on it? When there is that much head room it works out much better to stand the furnace(s) upright.

[carestx]

Understand the concept of Reletive Humidity, but don't understand why this system can't get it under control. Even when the RH outside the home is in the 20% range, inside my house the RH is still in the 60%. A good example would be to look @ the AirAdvice readings for yesterday . We ended up shutting the system down around noon and opening the windows and the RH inside the home dropped to 40% in less then 30 mins. even though the temp. remaind consistent. In the past as soon as we close up the home and turn the system back on, the RH builds and surpasses the outside RH very quickly and again the inside temp.remains close to the outside air maybe 3-5 degree difference. Don't see that being a large enough differnce to present as a 50% higher RH?