Heat pumps: oil backup and scroll vs 2 spd recip compressor

dave_in_va_2008

15 years ago

I'm looking at replacing my 15 year old AC and oil furnace with a heat pump and was hoping someone could address the following issues:

1. I'm considering either a Carrier Infinity 16 SEER two speed or Performance 15 SEER single speed compressor. I noticed that the Infinity 16 is a reciprocating compressor and the Performance (as well as the Infinity 19) uses a scroll compressor.

Will I notice the difference in the temperature of the heat coming out of the vents between the two units? I've read that scroll compressors produce slightly warmer air, although I've also heard that two stage has additional energy saving and humidity control benefits. Regardless of the outdoor unit, I plan to go with the infinity control and a variable speed air handler. I have a 2400 sqft (plus basement) home and 3.5 Ton unit. The infinity only comes in 3 and 4 ton models, so the contractor recommended a 4 ton 2-speed outdoor unit.

Another issue -- I've considered a hybrid heat system with a variable speed fan oil furnace as backup heat since I already have the oil tank installed. However, it appears that at $4.00+ per gallon oil and Thanks,

Dave

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Comments (5)

tigerdunes
15 years ago
dave

first of all,I would ditch the oil furnace and go all high eff heat pump with matching var speed air handler.

here are my personal specs for a new system.

15 SEER,12+ EER, 9 HSPF
matching var speed air handler
full BTUs in both cooling and heating for your rated size
R-410a refrigerant
scroll compressor preferred
electronic defrost preferred
staged backup heat strips
thermostat that controls blower speed

Don't fool yourself-you will not get that toasty feeling from HP heat vs oil heat. But you won't freeze either and you should smile at your savings.

Yes, the Infinity 16 HP is a recip compressor with a 50-100 split on low/high stage. It is a successful system and you would achieve very little improvement in efficiency with the Infinity 19 HP.

I personally think two stg systems may be overated and not necessarily worth the cost difference.

The Performance 15 HP with matching var speed Infinity air handler/controller is a great system. Of course sizing is important of the equipment as well as the condition/sizing/insulation properties of your ductwork system which is normally overlooked. If you have any hot/cold spots in your home, now is the time to address these issues.

Another good sgl stg system would be Trane's XL15i or AmStd Heritage 15. But if you absolutely want two stg, then it's Carrier Infinity 16 or sister mdl Bryant Evolution 16 HP-no question.

I am attaching a fuel comparison calculator.

IMO

Here is a link that might be useful: Fuel Comparison Calculator
ryanhughes
15 years ago
I wouldn't worry about the discharge temperature out of the vents. The Infinity 16 seems to be a big seller around here. It's low stage capacity is more favorable than the Infinity 19's. I believe the Infinity system can control the temperature output to make certain the register discharge temp is warm. I'm in Maryland myself and personally wouldn't invest in the Infinity 19. With those oil prices, it would be more economical to just use the heat pump with electric backup. Unless you're partial to the oil heat, that's the route I'd go. Oil prices are on the rise.
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dave_in_va_2008
Original Author
15 years ago
Thanks for both of the quick replies. It sounds like I'm on the right track with an all-electric system and that either unit would be good.

One other thing I noticed about the Infinity 16 is it's also listed as significantly noisier than the Performance 15 in the carrier brochures. Not sure if that's due to the different type of compressor. I'm assuming it would be a bit quieter during the low-power stage operation.

- Dave
ryanhughes
15 years ago
The Infinity 16 is marginally louder than the Performance 15 from what I've seen in person. The Performance 15's low noise level really impressed me, but the Infinity 16 wasn't too bad--certainly nothing I couldn't live with. The features of the Infinity 16 easily weigh out the noise factor.
tigerdunes
15 years ago
dave

the average person would not notice any noise difference between the Infinity 16 and Performance 15 heat pumps.

One other thought. Your quoting dealer will need to check your electrical service/breaker panel to see if it has the capacity/size to handle the backup strip heat load.

IMO

Heat pumps: oil backup and scroll vs 2 spd recip compressor

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Heat pumps: oil backup and scroll vs 2 spd recip compressor

Comments (5)

tigerdunes

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