THERMASTAR ULTR-AIRE 100

[kkmcewen]

2000 SQ FOOT HOUSE WITH A FIVE TON UNIT IN NORTH TEXAS. i BOUGHT A HOUSE WITH TO LARGE A UNIT. It cools fine, i just have high humidity. Local a/c guys want to replace unit with correct size. The house is only two years old and I can fork over that much money. I was hoping I could put a ultr-aire in combination with current unit and it would remove the humidity? I am concerned about electricity and the warm air it puts out. Will my current a/c still be able to cool house down with a dehumidifier that is blowing warm air in? I would also like info on the fresh air option. Current plan is not to use it, mabee down the road? I forgot to mention at 72 I am running 54-60% humidity. Can I get it down to 45%.

[pstu]

I think it would serve well. My homeowner experience has been with a Santa Fe RX model which uses the same mechanicals in a different package. You might also be aware there is a brand new UA-90 model. Hopefully Teddy Bear will add his comments, he really knows this product line.

I think the heat would not be a problem, your existing 5.0 ton AC system could fight that easily.

Best of luck -- Pstu

[ek]

The 100-V should be a good choice. Becareful not to bring in too much fresh air or the system will run too much. You might also try dropping your fan speed a notch. If you change the fan speed let your a/c guy do it. The charge will also need to be check after the adjustment.

"Pigs get fat, Hogs get slaughtered"

[teddy bear]

Originally posted by kkmcewen
2000 SQ FOOT HOUSE WITH A FIVE TON UNIT IN NORTH TEXAS. i BOUGHT A HOUSE WITH TO LARGE A UNIT. It cools fine, i just have high humidity. Local a/c guys want to replace unit with correct size. The house is only two years old and I can fork over that much money. I was hoping I could put a ultr-aire in combination with current unit and it would remove the humidity? I am concerned about electricity and the warm air it puts out. Will my current a/c still be able to cool house down with a dehumidifier that is blowing warm air in? I would also like info on the fresh air option. Current plan is not to use it, mabee down the road? I forgot to mention at 72 I am running 54-60% humidity. Can I get it down to 45%.
True, downsizing the a/c decreases the cooling cycles during the partial load condition. At the start of each cycle several minutes of moisture removal is lost. But during low/no cooling conditions the a/c does not operate enough to remove the 7-8 gals of water necessary to maintain <50%RH. The dehu maintains <50 without any a/c operation. Ultra-Aire is available in 100V Upright or 90H horizontal. Both will handle upto 2,500 sqft. TB

[kkmcewen]

I WILL HAVE IT INSTALLED NEXT WEEK. IS THERE ANYTHING I SHOULD WATCH DURING THE INSTALLATION. WHAT I MEAN, IS THERE ANYTHING I SHOULD MAKE SURE THE CONTRACTORS DO? THEY SEEM VERY SMART AND KIND, BUT THE HAVE NEVER INSTALLED ONE. I JUST WANT TO MAKE SURE WE GET THIS RIGHT THE FIRST TIME AROUND.

[teddy bear]

The main issues are: The return duct to UA should be from the open part of the home. The supply from the UA should discharge into the plenum at a 90^ angle to the air flow, before ducts are branched. For attic installation, you need saftey drain pan with an independent drain under the UA. The air filter and front panel must be accessible for service. Thank you for the opportunity and keep us posted on the results. TB

[ac4me]

I live in Nashville TN. area. My house is around 3750 sq' with 10' or higher ceilings. I have the 135H. Works great to keep humidity in check. If you install it in the living area like I did, watch for sound.
The fan will make some noise. The control can be off, so have the HVAC guys make sure it reads RH accurately.

[kkmcewen]

My unit will be in the attic. I will have a return vent in a hall next to the living area. Will I get noise from that vent? How do I make sure the contol is accurate?

[ac4me]

The noise is from the fan inside the unit itself. I think if it was in the attic you would never hear it. Keep in mind I'm just a homeowner. I think my location is the worst to control sound. Therma-Stor will give you a small hand held RH meter with temp and time. It is close to right, just 2 points off.
I think my HVAC guy used a wet bulb gauge. He said it is very accurate. They checked it three times. The first control was perfect on the RH, but had some of the LEDS not working. They sent me a new one that all the numbers worked, but read 10 points higher than the first. That’s when I had the pros check it. So now I have the back of the first one with the front of the second one. We have had rain all this week with mild temps. The Therma-Stor has worked great. I had some guest over and some mentioned it was very comfortable. I had the humidity at 53%. I hope I helped.

[not a filter expert]

I didn't hear anyone questioning the location?

A UA100 is a vertical unit not designed to go in an attic, or actually an unconditioned space since it does not have the insulation that the UA90, UA135 and UA150 Horizontal models have.

UA135 would be a suitable model, if filtration is a concern then they have a good Focus Filtration module available as well.

Is a permit being pulled?
Are the code enforcement people strict? If so, I don't think that all the ThermaStor units carry a UL Listing. Be careful...I know from personal experience.

[pstu]

What planet are you on? I am a homeowner too, but one who has spoken directly with the Thermastor people on a couple half hour phone calls. They told me unequivocally that each model of the 100 pint/day series would have no problem working with the temperatures in a Texas attic. This would include the Santa Fe basement model, it would include the Santa Fe RX which is intended for indoor use. The UA-100 model was specifically sold for attic install before they had the UA-90, UA-135 and UA-150 models. They absolutely did NOT tell me I needed one of the other models because of high ambient temperatures.

Hate to be so blunt to you, but you are handing out misinformation to everybody who reads this board.

Regards -- Pstu

[poodleparties]

After reading many posts on this unit at this message board I decided to buy one for my < 2500 sq ft ranch home. I wanted both house-wide dehu before my new wood floors went in but also liked the whole fresh air thing. My normal HVAC folks had never sold or installed one. Decided to give them a shot anyway. I live 8 miles from Thermastor itself so went there and had a nice chat, found out that I needed more parts than salesman had originally programmed in and also how NOT to install it (seems that some HVAC guys like to be lazy and attach the UA return to the house return). My HVAC guys were enthusiastic and the service manager himself, plus one of his lead technicians, came out to the house for a pre-install site survey (I didn't want them to install it without a plan in place...). The manager and technician installed it yesterday. They had to use 8" diam flex for the run to the outside vent since it was more than 25 feet. All of us neglected to remember the installation advice about attaching flex to the UA inputs and outputs before attaching standard ducting, so the vibration noise is really loud. They're coming back with flex next week. Control is in main hallway, next to central air thermostat, and above dedicated UA return.

Anyway, I think it's working, but I hope I simply have a bad control. At first it sat at RH 53% for a hour, but then I realized that I had forgotten to turn the basement supply bypass damper valve from 100% to 20% (their recommendation) so the rest of the house was getting no air. Once I did that, the RH reading dropped to 49% but now is stuck at 49% no matter how long I run it (or even if I turn it off). Not bringing in fresh air. No windows open. RH outside variable, from 50-60%. I did breathe into the control and it jumped to 55% (although the temp didn't change) so it responds to something, but it doesn't do much good to have it always think the RH is 49% since I'd like 45% and that means it'll run forever. I don't have an accurate hygrometer. I think it's doing something since I had no a/c or UA on last night and woke up sort of humid, turned UA on (49% @ 77 degrees) and went back to bed. Woke up, seemed nicer in house, still read 49% @ 78 degrees. At one point turned on A/C (UA off). House got nice and cool. Still 49%, now @ 75 degrees.

I will be calling the HVAC guys on Monday, as well as Thermastor, but is there anything else we should be looking at besides the control? It's the digital one.

[Edited by poodleparties on 06-18-2006 at 12:08 AM]

[poodleparties]

Forgot to add, inside temp is anywhere from 75-78 and I am not attempting to run the UA100 at the same time as the AC.

Also another question, the blower for the UA seems weak in comarison to the AC (1.5 ton Trane, 20 years old). Is that to be expected or could that be another problem? I am judging merely be putting my hand in front of my supply registers in the house.

[wptski]

Originally posted by poodleparties
Forgot to add, inside temp is anywhere from 75-78 and I am not attempting to run the UA100 at the same time as the AC.

Also another question, the blower for the UA seems weak in comarison to the AC (1.5 ton Trane, 20 years old). Is that to be expected or could that be another problem? I am judging merely be putting my hand in front of my supply registers in the house.
Your AC/AH probably pushing a lot more CFM than the UA100.

[poodleparties]

UA rated at 225 CFM but I think that means right at the outlet, probably less when it gets up in the house. Don't know what the Trane does but perusing this site leads me to think that the Trane might push 400 CFM per ton, so 600 (it's not a variable speed) so that would explain the difference. Not a big deal, I was just curious.

[not a filter expert]

Apologies, I am not misleading anyone and I should have clarified this with - according to the STRICT Florida Building Codes, this is what is allowed or not allowed. You can install the unit anywhere you want, I am sure - however there have been a number of changes according to code. Selfishly I recommend the horizontal models again due to access, because of my ignorance and location, I am faced with structures built to withstand Hurricanes. These structures now, typically have a low-pitch, gable roof not allowing the installation of unit that is 42" tall (not including the duct work and/or fresh air inlet).

I would suggest following up with your State's Local Building Code Requirements. Also, check on the UL Listing, though ETA Listing may be established on all Thermastor's products, it will again come down to the requirements of your State's Local Building Code.


Originally posted by pstu
What planet are you on? I am a homeowner too, but one who has spoken directly with the Thermastor people on a couple half hour phone calls. They told me unequivocally that each model of the 100 pint/day series would have no problem working with the temperatures in a Texas attic. This would include the Santa Fe basement model, it would include the Santa Fe RX which is intended for indoor use. The UA-100 model was specifically sold for attic install before they had the UA-90, UA-135 and UA-150 models. They absolutely did NOT tell me I needed one of the other models because of high ambient temperatures.

Hate to be so blunt to you, but you are handing out misinformation to everybody who reads this board.

Regards -- Pstu

[pstu]

Good to hear that this was a misunderstanding and we don't have to butt heads over what is true. Thank you for such a level headed, informative reply -- I hope you don't think I was excessively hot headed.

I can certainly see the advantage of a horizontal unit in several ways. And now that there are several competing horizontal units, it's hard to not think of the UA-100 becoming obsolete soon.

Best wishes -- Pstu

[dadsair]

I have sold and installed both brands and I find that I like the 1700 best. One reason is that I get good support from aprilaire. Also I have had more problems with the thermostor products on average. But either way a whole house dehumidification system is a good investment if installed and maintained properly.