Recent comments in /f/newhampshire

redsoxpanama t1_j7h87lc wrote

Reply to Heat Pumps During Recent Cold Weather by thread100

Can you have a heat pump installed and have natural gas burner at your house? Kind of like play which ever one is cheaper or functioning based weather outside? My house is 25 years old. Not sure how well insulated it is. Would be nice to be able to rely on whichever source happen to be cheaper at the time as well as switches to the other if Temps dip into the negatives.

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magellanNH t1_j7h80ee wrote

Reply to comment by pistolbristol in Heat Pumps During Recent Cold Weather by thread100

Did you notice a big capacity drop off below 0?

We had a Bosch BOVA system installed this year and are very happy with it. But as expected, it had some trouble keeping up once the temp got down to 5 or 10 degrees. (it still was putting out lots of heat but apparently not quite enough).

I had the thermostat set up to switch over to oil at 5 degrees, so I don't know how low it could have run or how much heat it could put out below zero.

Again though. This is about what I expected. The Bosch Specs say our unit goes from around 38k btus of heating at 47 degrees, to 28k at 17, down to just 23k btus at 5 degrees.

https://ashp.neep.org/#!/product/66146/7/25000///0

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mcot2222 t1_j7h6vwz wrote

Reply to What would you tell your realtor if you just bought a house and zillow said it has already lost 100k in value? by NecessaryMistake9754

I know on the Seacoast and probably all of NH there are fewer homes being sold in the extreme winter months. This tends to mess up the zillow algorithms in my experience and you see dips. When the weather becomes warmer and there are more sales happening and more data you tend to see estimates rise.

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magellanNH t1_j7h61ni wrote

Reply to comment by Ok_Low_1287 in Heat Pumps During Recent Cold Weather by thread100

Right now natural gas can be tough to beat with a heat pump, especially when it's really cold out. OTOH, heat pumps are usually cheaper to run than oil or propane, even with today's higher electricity costs.

This website shows how much it costs to heat your house with various fuels given current prices (Look at $/MBTU for comparison)

https://www.energy.nh.gov/energy-information/nh-fuel-prices

The key is to know the heat pump's coefficient of performance (COP) at various temps. COP tells you how much more efficient a heat pump is compared to using a resistive heating element. A heat pump running at a COP of 2.00 costs half as much to run as a heating element. A heat pump running at a COP of 3.0 can heat your house for a third as much as using resistive heat.

Here's a data sheet that shows real numbers for capacity (btus/hr) and for efficiency (COP) for a modern low temperature heat pump at different temperatures (see table on right):https://ashp.neep.org/#!/product/34469/7/25000///0

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minimally_social t1_j7gsg1m wrote

Reply to comment by ProlapsedMasshole in Heat Pumps During Recent Cold Weather by thread100

The rating I was referring to was the "guaranteed operating range" of -25c to 21c on that page.

We dropped below that on Friday. The tech that came out said he was getting a bunch of calls with the same problem.

It wasn't all of them, but does seem to confirm that the -25C threshold is when the probability of failure increases.

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SheenPSU t1_j7gqh7g wrote

Reply to What would you tell your realtor if you just bought a house and zillow said it has already lost 100k in value? by NecessaryMistake9754

Don’t sweat it, prices fluctuate and Zillow isn’t always reliable. Walpole’s a nice town so I expect it’ll only rise for you

You’ve got land, you’re in Walpole, and you’ve got curb appeal. You’ll be fine.

Also, we just had our assessments done. Did you see a noticeable difference between the two?

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ProlapsedMasshole t1_j7gaiqf wrote

Reply to comment by minimally_social in Heat Pumps During Recent Cold Weather by thread100

It's designed to do that below operating temps. Bottom of page 10 in your manual.

This was the first time I've hit the limits on mine, but still see them as the best investment I've made in our house by a lot and really don't regret going hyper heat at all.

Our house still has legacy heating, so we were fine this weekend, but anyone concerned with this kind of setup exclusively could cover these edge cases with a space heater or two as a temp setup.

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Alternative_Copy_768 t1_j7gadnt wrote

Reply to Heat Pumps During Recent Cold Weather by thread100

Had a new Fujitsu Xtra Low Heating mini split single zone installed back in August that said is capable of heating to -15F. Outdoor thermometer was showing -12f at its lowest and its still was blowing warm enough air. Don't think my boiler ever kicked on (Have that set to around 60f).

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