13 SEER vs. 16 SEER

[vstech]

Heating with hot water coil brings in humidification and, therefore, a more comfortable heat while a standard furnace is "dry" heat and not very comfortable.

arrgh! I see this recommendation SOOO often, and it's TOTALLY FALSE! a hot water heating system is exactly the same humidity to the house as any other type of heating system.
I hear many stating that the lower temp of the water radiators don't vaporize the water in the house like a high temp furnace heat exchanger or electric strip will... false.
household humidity is determined by the amount of water in the home, and the temp of the air. you warm the air without adding humidity, and you get a lower relative humidity in the house. period.
tight leak free houses have higher humidity in the winter because the cooking/bathing/breathing we humans do, gets better retained than the houses that leak outside air in all the time.

water is a better conductor of heat, so it's more efficient at transferring heat from the fuel used to the air. that is the reason so many northern climate areas use it.
STEAM radiators do tend to release humidity when they vent, but if you check out most homes with steam radiators, you will find they have racks for water trays to add humidity to the house... it's not the heat source doing the humidifying, it's the rack of water evaporating...

[esabet]

arrgh! I see this recommendation SOOO often, and it's TOTALLY FALSE! a hot water heating system is exactly the same humidity to the house as any other type of heating system.
I hear many stating that the lower temp of the water radiators don't vaporize the water in the house like a high temp furnace heat exchanger or electric strip will... false.
household humidity is determined by the amount of water in the home, and the temp of the air. you warm the air without adding humidity, and you get a lower relative humidity in the house. period.
tight leak free houses have higher humidity in the winter because the cooking/bathing/breathing we humans do, gets better retained than the houses that leak outside air in all the time.

water is a better conductor of heat, so it's more efficient at transferring heat from the fuel used to the air. that is the reason so many northern climate areas use it.
STEAM radiators do tend to release humidity when they vent, but if you check out most homes with steam radiators, you will find they have racks for water trays to add humidity to the house... it's not the heat source doing the humidifying, it's the rack of water evaporating...

Wow, thank you for the detailed clarification. It makes much sense.

All that said, what is your opinion on the SEER selection as I have it outlined?

[dan sw fl]

..., what is your opinion on the SEER selection as I have it outlined?

What's the electric $$$/ kW?

Higher SEER is not likely to make a noticable COMFORT difference on Long Island.
What is your goal on IAQ, R.H. and temperature set-point?

[esabet]

What's the electric $$$/ kW?

Higher SEER is not likely to make a noticeable COMFORT difference on Long Island.
What is your goal on IAQ, R.H. and temperature set-point?

Here is the electric rate:



I am going to sound dumb now but what are IAQ and R.H.? As for Temp set-point, we like to keep the house at about 72 degrees. The house has a southerly exposure with lots of windows.

Hope that helps.

P.S. We had a Manual J Report prepared, would that help?

[BaldLoonie]

Rheem's M coils (Multiflex) are now gone. They were great coils. The N coils that are used now are very restrictive. Takes a strong blower to overcome the restriction to them.

[dan sw fl]

Here is the electric rate:



I am going to sound dumb now but what are IAQ and R.H.? As for Temp set-point, we like to keep the house at about 72 degrees. The house has a southerly exposure with lots of windows.

Hope that helps.

P.S. We had a Manual J Report prepared, would that help?

IAQ = Indoor Air Quality
R.H. = Relative Humidity

http://www.lipower.org/pdfs/account/rates_resi.pdf

LIPA - Long Island Power Authority
I believe you need to use a heat pump and use LIPA ( provided that's ACTUALLY your utility) rate R883

Rate 883/D883 - Residential, Water & Home Heating w/Heat pump
Applies to customers who use electricity for both water and space heating with an electric heat pump,
with the exception of fireplaces and coal/wood burning stoves,
and account must have been established after January 26, 1983.

Service Charge: Standard Rate ___$0.3600 $0.3600
Service Charge: “D” rate ________$0.1790 $0.1790

580/D580/581/D581 • 882/D882/883/D883

Time Period ___________________ June 1 - Sept. 30 ______________ Oct. 1 - May 31
Energy Charge: (per kWh)
First 250 kWh _________________ $0.0857 ________________________ $0.0857
Next 150 kWh _________________ $0.0975 ________________________ $0.0787
Excess 400 kWh _______________ $0.0975 ________________________ $0.0515

With a Manual J report, a realistic estimate of monthly cooling & heating $$$ can be provided based on using a SEER 13/ HSPF ~ 8.5
and Heating & Cooling Degree Days.

Or perhaps, the Manual J report may have the annual energy use embedded in it somewhere.

[esabet]

IAQ = Indoor Air Quality
R.H. = Relative Humidity

http://www.lipower.org/pdfs/account/rates_resi.pdf

LIPA - Long Island Power Authority
I believe you need to use a heat pump and use LIPA ( provided that's ACTUALLY your utility) rate R883

Rate 883/D883 - Residential, Water & Home Heating w/Heat pump
Applies to customers who use electricity for both water and space heating with an electric heat pump,
with the exception of fireplaces and coal/wood burning stoves,
and account must have been established after January 26, 1983.

Service Charge: Standard Rate ___$0.3600 $0.3600
Service Charge: “D” rate ________$0.1790 $0.1790

580/D580/581/D581 • 882/D882/883/D883

Time Period ___________________ June 1 - Sept. 30 ______________ Oct. 1 - May 31
Energy Charge: (per kWh)
First 250 kWh _________________ $0.0857 ________________________ $0.0857
Next 150 kWh _________________ $0.0975 ________________________ $0.0787
Excess 400 kWh _______________ $0.0975 ________________________ $0.0515

With a Manual J report, a realistic estimate of monthly cooling & heating $$$ can be provided based on using a SEER 13/ HSPF ~ 8.5
and Heating & Cooling Degree Days.

Or perhaps, the Manual J report may have the annual energy use embedded in it somewhere.

Wow, thanks.

We never thought about H.R. or IAQ. How would a lay person establish the IAQ and H.R. anyway? We do intend to use ERV systems on both 1st and 2nd floor but that is because many are recommending it to us.

[dan sw fl]

I.A.Q. is addressed by ASHRAE Standard 62.2

CA version ..
http://www.energy.ca.gov/2010publica...0-2010-006.PDF

The process for exhaust-only ventilation system design is to: (1) determine the minimum
amount of airflow required: (2) select a fan or multiple fans that are rated to provide ventilation
airflow that equals or exceeds the minimum required; and (3) design and install a ventilation
duct system that meets the requirements of ASHRAE 62.2 Table 7.1.

(I.1) Whole-Building Ventilation Requirement Calculations
Equation 4.1a
from ASHRAE 62.2:

Qfan = 0.01 x Afloor + 7.5x(Nbr + 1)
Where: Afloor = conditioned floor area, ft²
Nbr = number of bedrooms; not to be less than one

Qfan = ventilation airflow requirement = minimum fan airflow rating, (CFM)

Example 1
2,500 sf house with 5 bedrooms
Qfan = 0.01 x 2500 + 7.5 x (5 + 1) = 25 + 45 = 70 CFM

Example 2
2,000 sf house with 3 bedrooms
Qfan = 0.01 x 2000 + 7.5 x (3 + 1) = 20 + 30 = 50 CFM