Energy costs

[joemach]

I have a customer who is getting natural gas on her street very soon. I see no way to run ductwork in a custom remodeled basement. Mostly hard lid. Low ceiling. If I put the furnace in what is now the mechanical room, she will have a 5-6' ceiling in some of the finished area in order to get the air where it needs to go. That will be pretty ugly. Lots of nice wood paneling that would need a bulkhead. 1960's house.

Anyway, I want to put a heat pump in the attic and a wall mount ductless in the basement. She is concerned over the energy cost of electric over gas. I am not a fan of putting a gas furnace in the attic, except if I went with an 80%.

Anyone know of how I could figure (and prove to her) that a heat pump could be just as efficient as gas.

I plan on using an air to air Bosch heat pump or possibly a ducted mini split for the first floor. This is a one story house.

She has an oil boiler now with baseboard convectors. She thinks it is costing too much and wantsto take advantage of pretty cheap gas.

[ga-hvac-tech]

One thing you could do... is build a small room in the attic enclosing the furnace/coil... so a condensing furnace would be in conditioned space (does not need to be the same temp as the house... just enough air to not freeze). Remember to insulate the PVC flue as soon as it is in un-conditioned attic.

Another thing would be to foam the bottom of the roof... thus turning the attic into semi-conditioned space...
Which would drastically lower her bills both for heating and AC...

OTOH... mini's will produce good usable heat down into single digits or some work to negative temps...

Just some ideas.

[beenthere]

Or tear out the oil boiler, and put in a gas fired boiler.

[joemach]

Or tear out the oil boiler, and put in a gas fired boiler.

But that does not give her a/c.

[timebuilder]

The key is indeed cost.

Electric heat strips are 100% efficient. They are also the most expensive way to heat anything in 2019, unless you have an acre of solar panels, from which you can never recoup the up front expense without a government program.

Gas is plentiful and much cheaper. You can never convince any sane person that electric will cost as little as gas.

[hvacker]

This might not work but often a supply duct can be run along a wall and boxed in. Even over the door as long as 6'8" ( I think) Code won't allow low ceilings most times but keep above door height.
There is software out there that will give comparisons with different fuels. If the basement is below grade and the remodel considered OS wall insulation, I doubt the owner would notice the difference in costs.

[Sooty]

Switching to a gas boiler right off the hop will save her money over oil that is a fact -make it a combi system and she will save a little cash by not heating a big tank of water. Use a minisplit for the cooling it won't be ideal but she doesn't have anything now anyway. I've never seen a forced air system put in as a retrofit job that turned out all that great without the house being a complete teardown remodel.

[kangaroogod]

I too despise 90%ers in the attic. Put a sealed combustion furnace in an upstairs closet and duct it up.

'The more you know, the more you realize you don't know'

[STEVEusaPA]

I'd doubt gas is 'very cheap' compared to oil. I wouldn't promise her amazing savings.
Heat Pump with gas or oil back up would be better, depending on electric rates.

[kangaroogod]

Could always go the unico route with a hot water coil. Did a job several years back, unico in the attic with a hot water coil. Used a plate heat exchanger so we could run glycol. Heated the plate with a tankless water heater which did domestic water and heated the plate. It was a bit complex but it works mint

'The more you know, the more you realize you don't know'

[beenthere]

But that does not give her a/c.

No, but it will greatly reduce her heating bill.

A heat pump with electric aux heat won't be cheaper for heat than nat gas.

A high velocity A/C may be a good choice for her home.

[kdean1]

There is something to be said for the practicality of a heat pump for the second floor. Certainly the envelope should be well sealed, perhaps going to the extent of insulating the roof deck with spray foam. The heat load for the second floor will be lower because of the conditioned space below.
The advantages of separate systems for each zone/level are obvious when it comes to even air distribution.
Do the best you can to give the customer the potential benefits but the decision has to be left up to them. If you persuade them against their feelings, they’ll blame you for any little thing they don’t like about it after the installation.

[hvacker]

In PA maybe because it's a basement with a small cooling load, a large de-humidifier might handle the load enough that a/s isn't necessary. I did that once in Ill.