Any Frigidaire AC experts here

[Luis-Pasco]

I had a new 14 seer Heat pump and variable speed furnace installed and am wondering if my system has dehumidificaiton feature. I can provide the furnace # and heat pump # if needeed? I am using a Vision Pro thermostat and do not see this feature on my thermostat.

[dash]

Post all the model numbers ,including the stat.,someone here will likely know.

I hope it does have dehumidification control,as you went with a larger system,without a load calculation.

http://www.hvac-talk.com/vbb/showthread.php?t=158774

[beenthere]

The 8321 has cool to dehumidify.
It doesn't have the ability to slow the blower though.

[BaldLoonie]

The air handlers have had this capability for a while, the gas furnaces are just now adding this feature -- assuming you mean the dehumidify on demand that the Vision Pro IAQ is capable of.

[TMH58]

The blower has the ability to slow to 75% of the selected cooling cfm for maximum dehuhidification on the furnaces and A/H. A qualified servicer would know how to wire in a humidistat.

[craig1]

the gas furnaces are just now adding this feature

i installed one 2-3 years ago (the old split manifold style) and it had Dehum terminals on the board where you adjust the CFM

[Luis-Pasco]

Post all the model numbers ,including the stat.,someone here will likely know.

I hope it does have dehumidification control,as you went with a larger system,without a load calculation.

http://www.hvac-talk.com/vbb/showthread.php?t=158774

I have 2 neighbors in my neighborhood who had the load calcs done and they each have a 4 ton system(Same house as me. Facing the same direction and the closest one is one block over). I tried to get one done, but i was freezing with no heat pump in winter at the time. My wife was not happy and i lost $1000 in saltwater aquarium life from my system not working and was going to loose more. I had to make the best decision at the time and i feel i made the correct one. The other 2 techs that came over were horrible.

This tech added another return and that has made the house cool and heat more evenly since I have had the new system.

Their are some minor gripes with my install but I won't get into that.

I will get my model #'s tonight and I am using a Vision Pro and iwll get the model #.

[Luis-Pasco]

Furnace Model # B5VM-T49K-C and Heat Pump Model FT5BD-048K.

Thermostat is a Vision Pro Model # TH8320U1008

[beenthere]

That stat doesn't do cool to dehumidify.

The YTH9421(known as the IAQ stat), would get you abetter use of your system.
So would the Th8321. Not as good as the IAQ though.

[Luis-Pasco]

That stat doesn't do cool to dehumidify.

The YTH9421(known as the IAQ stat), would get you abetter use of your system.
So would the Th8321. Not as good as the IAQ though.

Thanks I figured that out last night after researching it a bit more. I will get the correct one.

[dash]

When they come back to install the stat,be sure to ask what they set the air handler to,as far as cfms(air flow),I'd recommend 350 cfms per ton ,for Florida.

[beenthere]

Dash.
Since the IAQ can keep the blower slowed down the entire cooling call. Which would be less then 350 per tom for many units. Do you still recomend 350 per ton for Florida for systems using the IAQ.

[adrianf]

I'm no Dash but I'll say that the 350 proves optimum. With the Southwest Florida summertime due point average being 74 degrees the less run time at the reduced discharge temps the better. The 350 per ton still provides improved dehumidification which reduces the amount of cool to dehumidify operatioin and in my book thats a good thing.

[beenthere]

My point is, that if the blower is set to 400 CFM per ton.
If the humidity is above set point. The IAQ will slow the blower down.
To about 332 CFM.
If the humidity is below set point, it will let the blower run at its set 400 CFM, giving higher efficiency.

[Luis-Pasco]

My point is, that if the blower is set to 400 CFM per ton.
If the humidity is above set point. The IAQ will slow the blower down.
To about 332 CFM.
If the humidity is below set point, it will let the blower run at its set 400 CFM, giving higher efficiency.

I will check tonight to see what the CFM was set to.

Thanks for the info. I am also ordering the IAQ stat as well as an outside sensor.

[dash]

I'm no Dash but I'll say that the 350 proves optimum. With the Southwest Florida summertime due point average being 74 degrees the less run time at the reduced discharge temps the better. The 350 per ton still provides improved dehumidification which reduces the amount of cool to dehumidify operatioin and in my book thats a good thing.

What he said.

Ideally it might be nice to have it go to 400 cfms per ton,at or near design conditions,for the higher efficiency.

[adrianf]

Your point is taken and is correct. But my primary interest is the structure, its components and occupants. Given the typical SHR of the current crop of air conditioners and considering the local climatic conditions the resulting runtime when operating in the cool to dehumidify mode and pushing 50 degree air through duct in an attic with a dew point of 75 degrees or higher will have less than desirable results.

[SBuckJ]

Two of the dipswitches need to be set in that air handler and it will have the dehumidification mode. I believe it is dip switches 7&8 however you should have the installers come back and do so.
SRJ

[Luis-Pasco]

Two of the dipswitches need to be set in that air handler and it will have the dehumidification mode. I believe it is dip switches 7&8 however you should have the installers come back and do so.
SRJ

allright just got off the phone with my A/C tech and he told me my system does not have this feature. If that is the case i am pissed as i asked for it on my original install and have spent a ton of cash on this setup.

Now i see why us customers get pissed off and get on these boards to rant. These a/c installers have NO CLUE what they sell us. I am very upset as this system was not cheap and i got a half ass job.

[Luis-Pasco]

I just checked and my switches 1-8 are all ON.....