Parents looking for new heat

llamaboy

My parents have a, roughly, 50 year old house. A1700 square foot ranch house in northern Indiana. they're getting tired of their high electric bill (400-600 during the winter, 150-400 during the summer). They have electric baseboard heating and have to install a window air conditioner every summer. Their house sits on a crawl space (maybe 18" to crawl through), so it would most likely be too costly to run duct work under there. My question is, should they go with a propane furnace/ac unit mounted in their attic (either high efficiency with heat tape wrapped around the condensate drain, or a low efficiency with no worry about a condensate drain), or a heat pump unit (something like those Mitsubishi or Fujitsu units mounted in the attic as well). Either way they go, they'll probably keep their baseboard for at least a few years as a backup.
I've heard good and bad about both types of set ups, but unfortunately just don't know quite enough to give a good answer. Thanks for any help!

-Joe

SWEI

What are their costs for electricity and natural gas (if available) like?

What city (so we can look at the annual heating and cooling degree-days there)?

llamaboy

They live in Fort Wayne, Indiana.
The average cost of kwh is about $0.10, and propane would be roughly $2/gal. NG is not available to them unfortunately.

Zman

Those are some high bills!
How is the home insulated and air sealed? What type of windows?
From an energy point of view. $0.10 electricity costs about as much as propane at $2.45 (burned at 90% efficiency). I bet your long term average for propane is more like $2.50.
I would start by taking a hard look at the building envelope then look into either a mini split system or a heat pump forced air system.

llamaboy

Thanks for the response! I know the attic is decently insulated (orginial blown in insulation, covered by r11(?) rolled batting. The walls have the typical r11 bats. They know part of the issue is their floor is uninsulated from the crawl space. Plus, they're going to start replacing/repairing windows in the next month (large picture window allows for a lot of heat transfer).

Rich_49

If the attic is ventilated run baffles up from soffit to ridge , install, ridge vent if there is not already one . locate ducted system in attic , this will now be inside the thermal envelope . get a high efficiency propane water heater , set it up to do the Fan coil in an air handler along with DHW . A/C coil for that and you're done . Best job you're gonna get done . Moving the insulation from the ceiling to the attic plane will also cut down on the heating and cooling loads although it may not seem so . Insulate that floor also in the crawl

JUGHNE

What I have done in a similar situation when the people were tired of burning wood and did not want to replace their LP furnace was to add a multi mini split inverter system.

One outside unit and 3 inside units. Linesets were run in basement, (in your case crawl space). Inside units were installed on inside walls with linesets hidden in closets or boxed out in non public rooms. Some electric heat was added although they still wanted to burn wood on serious winter days.
In your case just keep the BB heaters. At maybe 10 degrees or so the heat pumps will not produce enough heat.
No attic work.
No LP tank, regulators or piping.
Little crawl space work.
Here an air to air heat pump cuts the electric bill by 1/2 to 1/3.
Great AC comfort, good dehumidification and quiet operation.

My heat gain/loss design logic with inverter heat pumps is to oversize the unit (within reason) to gain advantage needed during heating season and that during cooling season they will modulate down as needed.

I hope someone here will correct me with explanation if I am far off base on this assumption of oversizing.

John Mills_5

Mitsubishi has come out with (or will be) a conventionally ducted air handler for their hyper heat unit. Certainly won't be cheap but if you are looking at several wall units, it may be a good option plus you have air everywhere. Many mini brands have ductable air handlers now but they are very limited in how much ducting can be on them.

If the cost of minis scare you, a good air source heat pump with electric backup in the attic would be what we usually do down in Indy in a case like this.