Heat Pumps - Article

An interesting read… We jumped in last year adding the heat pump air conditioner to our relatively new Trane NG furnace. Earlier projects had replaced old sheet metal, asbestos wrapped ducts with new, flexible, insulated ducts, and few larger vents, getting us better overall circulation. But we may have jumped too soon, missed 2023 rebate programs, but, it did help with last year’s heat waves. Being in Sonoma County, CA, we’d gotten by many years with no A/C, using a whole house fan I put in 20+ years back. Utility bills have increased for everyone as the PG&E company has hiked rates, attempting to recover their firestorm losses… ~$400/mo is where we are, even after this heat pump, others, less careful friends are hitting ~$500,~$600 bills… so we watch for articles like this one… Recovery for NG systems aren’t as great as others, at the bottom of the chart…

2 Likes

Good stuff, thanks!

I’ve got oil fired hot water baseboard heat, two zones. My last oil delivery was $600. The next will certainly be worse. The boiler is quite new, and efficient for its type.

My central air is due for replacement. The unit on the slab outside is original to the house, 1989. (I sent the serial number and such to the manufacturer and they told me the year.) The air handler (two zones) in the attic is far newer, but they share a refrigerant that is not longer usable, so they both must go.

I started doing a bit of reading about heat pumps vs AC. A lot of it seems to be what my daughter has, “splits”, rather than central. One thing I did come across was the statement not to expect them to last as long as a basic AC unit.

My intention is to start with choosing a local HVAC outfit with years in business and a reasonable reputation - there seem to be two and I’ll talk with both - and see what alternatives they offer. The ducts that are in place for the two zones are fine, so they will be told to use them as is.

1 Like

Yes, long term, a local, reputable dealer is worth a lot… We’ve used the same fellow before when we replaced the old contractor’s Carrier NG furnace, fixed up the plenum and return air ducts at the time… Good guy, good to work with… Friends, neighbors, family also use his services, I think we just jumped to quick, nit his fault we didn’t get an Energy Star unit which would have qualified for some decent rebates… Haste makes waste, I guess…

Your system is a lot more complex, we’re one zone, ~1500 sf home, single level, a little cozy in the rear area, but they managed OK with the ducting… Just glad I didn’t have to crawl it all… :slight_smile:

1 Like

So your ducting is beneath the floor, in a crawl space? Mine is in the attic. Room for me to stand down the middle of the main house, but I’ll never get farther than the landing at the top of the pull-down stairs.

1 Like

Sorry you did not keep KWhr usage.

Those numbers are in the old bills, no doubt, or online, haven’t tracked all that closely…

Will be interested to see what alternatives you get quoted. Obviously the “splits” are ductless. I had 3 splits with the “hyper-heat” feature as well put in last June, one sizable compressor outside. They were phenomenal at cooling and ok at heating, but man when the temp dropped below 40 the compressor ran all the time. My Kwh use went up 2.5x in December over last year. Since the rates had gone up 90%, I turned them off and went back to the FHW-oil: used 4% less electricity in January than a year before. I had hoped the major reduction in oil consumption would save a few hundred $. Not the case at our “brave new world” electricity rates up here.

Every system has strengths and weaknesses. And you may live in one of the geographically small areas that will find all electric is not the least expensive way to heat. However using national, state and metropolitan average prices for electricity, fuel oil and natural gas electricity is clearly the lowest seasonal heating cost.

Certainly if one has a dual fuel system one can lower seasonal/annual cost further by switching from electricity when the temperatures are below some temperature. Don’t know the cost to add dual fuel, but when I looked into it there was no way to justify the added equipment cost. The major natural gas company here in Georgia charges way more in fees & distribution costs in December through February compared to May through September.

The way you describe your system, I expect you do not have inverter compressors - they cost a bit more, but that is where the big difference enters. My systems run more hours and a lower power consumption and higher efficiency at least 85% the time. Back in December when we had temps between 8 and 16F for almost a week it did run pretty much continuously at full capacity.

1 Like

Does this mean you can’t turn down the thermostat at night when it is that cold as it would be too slow to warm up again in the morning?

For us your question does not have a yes or no answer. Our current house is about 3200 sqft with two heat pumps. One is 36,000 BTU (3 tons) that does the house. The other is 24,000 BTUs and does a Bonus room over the garage (read that as stand alone room, lots of exterior wall surface) plus an enclosed porch – 3 sides 8 foot tall windows and a door. So the heating in the mornings is somewhere in above 36,000 BTUs for our living area. We do turn the temperature down at night to 68F in the heating season - daytime temperatures 72F. (Summers we cool to 75 and lower things to 71 at night.)

There is no way our house will heat as quickly in the mornings as a typical gas furnace which when matched in the Carrier name plate with our 3 ton air-conditioning unit would have an 85% efficiency 75,000 BTU heating capacity. (.85 times 75K = 63,750 BTUs)

In actual fact during the cold snap I referenced, I did turn on the gas log fire place unit and a gas stove burner. Took about a hour to get things toasty.

More recently we have had weather that got down to 30F at night. We tell the smart thermostat to have our house up to 72 at 7AM. The thermostat sense outside air temp and fires up the Heat Pump to me on temp at the specified time. We have not experience any problems meeting the desired temp without the resistance/auxiliary heat when the exterior temps was 30 or above. Below 30 the resistance heating is needed.

On those cold days in December our electric heating costs were $12 per 24 hours - we pay 10.5¢ per KWH for electricity. (Smart Thermostat has summer and winter electrical costs and tells us what the cost of HVAC is. )

Incidentally the default with this system will not let the house at night get to the set point if the added cost of resistance heating exceeds the savings for lower interior temperature at the time of programs morning wakeup. We can over right the default if desired.

1 Like

We are set up to 68° daytime, 65° nights, summer, not sure where we’ll land, likely only bother with cooling on 100°+ days, generally the coastal breeze somes in, whole house fan cools things down OK…

Count yourself fortunate. If we were still paying close to that for electricity I would be running the hyperheats all the time. But because we got nailed up here with a 110% spike in the electricity generation rate 2 months after I got them, (not the transmission rate), we’re now paying 33C / Kwh total. The “choice” is $4+/gallon for oil, a 50% increase from a year ago.

2 Likes

Curious – where are you located?

I’m not Flying Circus, but the total per kWh rate for me here in Connecticut is $0.34. (Which was a bit to my advantage last month as my solar system ran a net surplus of 478 kWh.)

I’m in New Hampshire. Eversource is the utility. I was able to contract out the generation portion to North American Power for 15% off.

Hi @FlyingCircus -

Whenever I’ve looked at these alternative suppliers there always seemed to be a catch. The rate that they publish “today’s rate” is not set in stone, so I have seen from friends who went down this path that the rate increases over time to the point where the supplier rate is no longer a cost savings. Do you know if your rate is locked in?

Do you live in an area where the Town or County has contracted with the alternative supplier which has guarantee the rates?

I’ve always been reluctant to switch when presented these offers - and I have looked into them more than once and came away with - an “ah ha” moment when I see “there’s the catch”. I’m in MA and our town does not offer any contracted group energy suppliers.

I used to work in IT for both Boston Gas and Boston Edison back in the day, and lived through the period of de-regulation which unbundled supply and delivery. It’s a very complicated supply chain.

Thanks,
'38Packard

2 Likes

Locked in for at least 6 months, may be 12 I’m not sure. Penalty for early termination.

No, it’s at the state level - NH opened the power generation contracting to the national grid or whatever it’s called, consumers see what’s available for contracted generation rates (including choices for green/clean mix) and pick their supplier. Eversource is the sole “transmission” provider and that’s guaranteed.

1 Like

Please keep us posted on this. I don’t mind having a look at it again if the rate stays lower than Eversource supply rate across the 12 month period.

Thank you!!
'38Packard

1 Like

My memory may be wrong –

Unless people were under a rock, it was hard to miss that during the winter of 2021Texas had a nasty grid failure – Senator Cruz flew his family to Mexico and said he was leading help to Texas residents.

When the failure happened more than a few contract power resellers were sending out monthly bills in the tens of thousands of dollars – they were selling power at the spot rate plus something. Since Texas is not connected to the national grid and Texas providers were at capacity, pricing faced an almost vertical supply/demand curve.

Fine print becomes really important when significant delivery/production problems people view as “that ain’t gonna happen” occur.

3 Likes