Frigidaire IQ Drive - No Option to Disable Dehumidifier!

[allan38]

Hmm, checks out to be a 22+ seer system according to the google search I did. Frigidaire is a brand licensed by Nordyne for Air Conditioning. The latest version is 24.5 seer.

The system is designed to slow down and run at a fraction of it's capacity using a fraction of it's normal power consumption instead of shutting off. It runs constantly to keep the temperature at thermostat setpoint. It doesn't have the high startup energy consumption created by multiple starts and stops. This isn't your grandmother's air conditioner.

I had a customer with the same complaint with a Trane two stage heat pump during the winter. He purchased the home from the family who had it installed.
It wasn't too hot or too cold. It just never shut off. It would maintain temperature and drove the guy nuts because he expected it to shut off. He never had high power bills, just continuous comfort.

Is it getting too dry in your house or colder than setpoint? Have you had higher electricity bills than your neighbors with similar homes?

[SW Florida Kid]

Hmm, checks out to be a 22+ seer system according to the google search I did. Frigidaire is a brand licensed by Nordyne for Air Conditioning. The latest version is 24.5 seer.

The system is designed to slow down and run at a fraction of it's capacity using a fraction of it's normal power consumption instead of shutting off. It runs constantly to keep the temperature at thermostat setpoint. It doesn't have the high startup energy consumption created by multiple starts and stops. This isn't your grandmother's air conditioner.

I had a customer with the same complaint with a Trane two stage heat pump during the winter. He purchased the home from the family who had it installed.
It wasn't too hot or too cold. It just never shut off. It would maintain temperature and drove the guy nuts because he expected it to shut off. He never had high power bills, just continuous comfort.

Is it getting too dry in your house or colder than setpoint? Have you had higher electricity bills than your neighbors with similar homes?

I finally found out how to turn off the dehumidification.

The A/C is running all day like you explain in your post. I live in one of those communities that have 200 houses based on 5 floorplans, so everyone has the same house. My neighbors electric bills are around $100-120. Mine is $190-$220. I have a 1299 sq foot house. The A/C stays at the temp specified and has no problem reaching the temp I program it to be. It just runs all day at 900-1200 rpms. All day, all night, it never shuts off.

[SoFlaDave]

Sounds like normal operation especially if you're maintaining 72 in this weather. The difference between your bill and your neighbors bill might be as simple as a 3 degree higher set point. When's the last time the system was serviced?

[tedkidd]

Why do you want your system to shut off?

Is it noise?

Is it comfort?

Do you think a higher humidity setting will save money?

Are you jumping to conclusions with too little information? (It's likely that LOWER humidity will allowa HIGHER tstat setting, in turn saving money.)

If you are unhappy with your bills, your best options are to have the unit serviced regularly and change the filter frequently. and have a comprehensive energy assessment to understand the cause of your high bill and options for improving it.

As Allen mentioned, that's a high zoot system that people today still don't comprehend. It is designed to gently and continuously keep your house cool and dry whereas most only understand the crappy teeter tauter systems that are about to follow the horse drawn buggy.

But if you have equipment in the attic all energy cost bets are off. All KINDS of potential issues with that. You are cooling a 150f oven, "ain't never gonna be cheap.".

[mark beiser]

I finally found out how to turn off the dehumidification.

The A/C is running all day like you explain in your post. I live in one of those communities that have 200 houses based on 5 floorplans, so everyone has the same house. My neighbors electric bills are around $100-120. Mine is $190-$220. I have a 1299 sq foot house. The A/C stays at the temp specified and has no problem reaching the temp I program it to be. It just runs all day at 900-1200 rpms. All day, all night, it never shuts off.

That is normal operation for an IQ drive system.

When they replaced the system, were any changes made to the duct system, or sealing work?

Installing an IQ drive system on a leaking, poorly designed/installed, over sized, and/or poorly insulated duct system is a recipe for disaster.

[jtrammel]

That is normal operation for an IQ drive system.

When they replaced the system, were any changes made to the duct system, or sealing work?

Installing an IQ drive system on a leaking, poorly designed/installed, over sized, and/or poorly insulated duct system is a recipe for disaster.

We installed a 3 ton iq drive a year and a half ago replacing the 5 ton gas package unit. Replaced all ductwork, properly sized and sealed to 3% duct leakage and encapsulated crawl space. The customers electric bill decreased by 60% and natural gas by 50%. The system rarely shuts of and maintains 74f in summer and 39% rh winter at 69f

[chuckcrj]

We installed a 3 ton iq drive a year and a half ago replacing the 5 ton gas package unit. Replaced all ductwork, properly sized and sealed to 3% duct leakage and encapsulated crawl space. The customers electric bill decreased by 60% and natural gas by 50%. The system rarely shuts of and maintains 74f in summer and 39% rh winter at 69f

This is great, the perfect way to cool a house, one btu enters, one btu leaves. Temp and rh is constant.

[mark beiser]

We installed a 3 ton iq drive a year and a half ago replacing the 5 ton gas package unit. Replaced all ductwork, properly sized and sealed to 3% duct leakage and encapsulated crawl space. The customers electric bill decreased by 60% and natural gas by 50%. The system rarely shuts of and maintains 74f in summer and 39% rh winter at 69f

Yeah, when done correctly, they are really great systems.
When thrown in on an existing leaking, under insulated, incorrectly sized duct system, they are an absolute disaster.

Even if there is no leakage, heat gain in attic installed duct systems is a VERY serious issue with variable capacity systems, even with ducts that are "correctly" sized for the maximum capacity of the system.
The systems rarely operate at their maximum capacity, and spend a great deal of time operating below 50% capacity.
The greatly reduced air velocity through the ducts allows for much greater opportunity for heat gain.

I'd even go so far as to say it is best to slightly under size the duct system for a variable capacity system, especially if it is in an unconditioned space.

Even if the existing duct system is designed, installed, and sealed properly, if it only has R-4 insulation on it, I'd upgrade to R-8 wrap if it is metal, or replace it with R-8 duct if it is flex.

[tedkidd]

This is great, the perfect way to cool a house, one btu enters, one btu leaves. Temp and rh is constant.

So nicely put Chuck!!!

Like gently idelling along the highway with cruise control on. Not banging equipment on and off. Not putting throttle to the floorboards?

How do we get people to understand this shifts control strategy paradigm 180 degrees?

Mark, good points. Really enjoying your posts too. But putting an ice cube in the oven should be addressed by turning the oven into a refrigerator. Might want to avoid "work arounds" recommendations.

Inside the duct is the greatest delta to outside experienced by the whole enclosure (building envelope). Therefore, wouldn't it make sense that it have the greatest insulation? Easiest to just make the duct "indoors". And by making that recommendation you shift responsibility for comfort and energy cost back to the homeowner. That's where it belongs.