Variable spd Air w/single spd HP?

[rlevitt]

Can anyone tell me if there is any advantage to having a variable speed air handler with a single speed heat pump that is worth the ~$+ cost over a fixed or multi speed one?

I am in Sarasota, FL only from mid Oct to mid May. My house requires a 3 ton unit.

[RyanHughes]

Better airflow assuming a ductwork system that is partially deficient/undersized, since the blower can adjust to maintain a set CFM whereas standard blowers just don't move as much air. Can be configured to control humidity by reducing airflow when needed (with proper installer setup and/or use of a thermostat that controls humidity). Tend to yield higher efficiency ratings. Tend to be quieter in most cases (unless the ductwork is in such poor shape). Just to name a few... Post the particular model numbers of equipment you are looking at (if you have them) for further suggestions on equipment combinations/ratings. For example, Carrier 25HNA936, FE4ANF005, etc.

So to answer your question, yes. There are benefits to having the variable speed blower with or without the two stage outdoor unit.

[rlevitt]

Thanks for such a fast reply.

Looking at the Lennox 14HPX036 with either a CBX27UH-036 or a CBX40UNV-036. Difference in price is ~$ after all the rebates and tax credit.

[RyanHughes]

The CBX27 is a good air handler and will bring with it good efficiency ratings since it has the X13 motor (which isn't variable speed but is a high efficiency motor). The CBX40UHV-036 has the advantage with the variable speed motor and the fact that it includes a media air cleaner (which I assume the dealer explained to you). Though personally, if I were to go with the high-end indoor unit, I would see if I could spend a bit more to get an Elite series outdoor unit, such as the XP14-036--nicer cabinet and a bit quieter. If not, the base quote you have, I would say, is a fine mid-grade system. Ultimately it's the consumer's decision based on their circumstances. How much they want to spend upfront, how much added comfort/efficiency is worth to them (and again, for best humidity control a "good" thermostat is suggested to be used with that air handler, such as the Honeywell VisionPRO IAQ), longevity of equipment, how long they plan to live in the home, etc... Good luck with the decision. Make sure you feel comfortable with the company you are working with first, as that will make the big difference.

That's my perspective. We'll see if anyone has any different opinions to offer regarding equipment selection. In your area, I'm sure humidity concern is a priority. But that isn't to say a more standard system without bells/whistles can't keep you comfortable.

[beenthere]

Questions and discussions pertaining to HVAC for the home. No pricing, no DIY, Thank You.

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[SBKold]

The CBX27 is a good air handler and will bring with it good efficiency ratings since it has the X13 motor (which isn't variable speed but is a high efficiency motor). The CBX40UHV-036 has the advantage with the variable speed motor and the fact that it includes a media air cleaner (which I assume the dealer explained to you). Though personally, if I were to go with the high-end indoor unit, I would see if I could spend a bit more to get an Elite series outdoor unit, such as the XP14-036--nicer cabinet and a bit quieter. If not, the base quote you have, I would say, is a fine mid-grade system. Ultimately it's the consumer's decision based on their circumstances. How much they want to spend upfront, how much added comfort/efficiency is worth to them (and again, for best humidity control a "good" thermostat is suggested to be used with that air handler, such as the Honeywell VisionPRO IAQ), longevity of equipment, how long they plan to live in the home, etc... Good luck with the decision. Make sure you feel comfortable with the company you are working with first, as that will make the big difference.

That's my perspective. We'll see if anyone has any different opinions to offer regarding equipment selection. In your area, I'm sure humidity concern is a priority. But that isn't to say a more standard system without bells/whistles can't keep you comfortable.

As a contractor in our humid environment....RyanHughes is right on. Pair it with at least a Honwywell Vision ProIAQ or better yet a Prestige HD thermostat for built in dehumidification control. Of course it does need to be installed right to get any benefit from it but if it is is.....You will really enjoy the comfort.

[rlevitt]

Thanks to RyanHughes and amassuperbike for your very helpful advise.

rlevitt

[SBKold]

To clarify a little more I would specify a true ECM Variable speed blower over a unit with the X13. It has many more features and is easier to integrate dehum thermostat. Your contractor should be able to help you know which model has which motor.

Im just not familiar with Lennox.