Heat Pump or Gas in Austin Tx

Stuking21

New member
Dec 10, 2019
3
Austin
Hi All,

I'm a new pool owner and also new to the site. Have heard great things about TFP!!! Looking for guidance regarding heater replacement.

I've owned my new home for 3 months. We have a gas heater with inground 16k pool and spa. The heater is archaic and has not worked since we've moved in. I'm looking to replace and considering electric heat pump vs gas heater.

I understand a heat pump will take a long time to heat the pool and have heard spa will take 45 min for heat pump vs 15 min with gas. My main concern is not buying a unit that will cost significantly more per month to operate. Does anyone have experience with electric heat pump? I'm okay taking a few days to raise our pool temp with a haet pump if the cost will be significantly less to maintain temp than a gas powered. Will a heat pump have trouble raising a 16k gallon pool to 80-85 degrees in Austin while temps are in 50s 60s? Can it raise a spa to 102 or are their limitations? Any insight on regarding temps and cost comparison would be greatly aporeciated
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,219
Tucson, AZ
Go online to the Pentair website. Under there pool heater section they a cost comparison calculator for heatpump versus gas (NG or propane). It will give you a good cost comparison fir your area as it uses local and regional data for utility costs.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
12,868
Northern NJ
Pentair has a Heat Pump Calculator to determine the appropriate size Heat Pump for your location. Pentair seems to do honest calculations based on the physics and efficiencies of each type of pump and energy source.

To get the most accurate cost comparison you should change the default electric kwh, natural gas price, and propane price to actual prices in your area.
 

Stuking21

New member
Dec 10, 2019
3
Austin
I'll check out the Pentair site. Hard to know who to trust being I went to a heat pump manufacturers site Aquacal, and their calculator showed $200 per month more average annual cost to run gas. Im guessing Pentair will be reverse. Hopeing someone can provide real life feedback who has run a heat pump in Austin Texas
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,219
Tucson, AZ
I don’t think the cost differences will be dramatic. The cost of heating a pool is influenced much more by how you operate the pool than the source of the energy (unless there’s a huge disparity in utility costs which isn’t typical). If you are diligent and cover a pool or spa every night so that there’s no evaporative heat loss and you don’t run your pump in such a way as to encourage heat loss, then either method is going to cost roughly the same. So, in many instances, the choice of heating source comes down to what you want to achieve. If you’re a die-hard spa user and you need that attached spa to heat up quickly, then gas is your best option. If you can afford to wait and don’t need the spa to get too hot, then HP is an option. In the heat of the summer months people rarely need to use their pool heaters (unless the pool is shaded a lot) so if you’re trying to get extra swim days in the shoulder months, a gas heater will get you there quickly but a HP running all the time may cost less.

Keep in mind that a heat pump is going to need its own dedicate 240V/60A circuit and so there’s going to be added installation cost beyond the cost of the heater.
 

jimbethesda

Gold Supporter
Jul 2, 2018
275
Austin, TX
I live in Austin, serviced by Texas Gas Service. I have a Pentair 400k BTU gas heater. I calculated it costs me $1.75/hour to run it. I have a 19,000 gallon pool and a 1,000 gallon attached spa. I can raise the temp of the spa about 1 degree every 1.5 mins and the pool 1 degree every 30 mins.
 

Stuking21

New member
Dec 10, 2019
3
Austin
Went to Pentair site and it's actually recomending a heat pump. I'm dubious as most I have talked to have said to go gas. Although both AquaCal and Pentair are recommending heat pump from their site. May want to listen.

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JJ_Tex

Bronze Supporter
Jul 17, 2019
694
Prosper, TX (DFW)
I understand heat pumps to be more "slow and steady" vs gas which is more instant. If you truly will be running your heater every day, that would not be the norm but a heat pump may be your best bet. Most people around here will use their gas heater to heat the spa and maybe kick it in the pool every so often for special occasions or to add a few degrees in the spring or summer.

Also keep in mind that Pentair sells both gas and heat pumps, so in theory they are not biased in their heat pump recommendation.
 

jseyfert3

Bronze Supporter
Oct 20, 2017
584
South-Central WI
That doesn't sound unreasonable. I did an initial look things in my area, and gas was recommended. But we have a short, cool season where extending the swimming season means you're operating the heat pump well outside it's optimal temp range, so NG wins on cost.

For a warm area like Texas, it doesn't surprise me in the slightest a heat pump is more economical to run.

If you know your specific utility rates (they should be listed on your bill, but be sure to add up all "per unit" costs as many bills split up distribution and supply costs but charge per kWh/therm for both), then you can re-run the calculator and enter your exact utility rates. There's an option to do that somewhere.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,219
Tucson, AZ
No one swims in Feb, that’s just too early. Cut off the shoulder months to March and October and you should see a more realistic number. Your pool is going to get used the most when the kids are out of school. I have found that when school starts up, pool use drops off like a stone .... and school starts in mid-August here in Tucson!!! So I wind up maintaining a swimmable pool for months with very little use (weekends only).

I would say this - if you plan to use the spa a lot and want fast heating, you’ve got to go with gas. You will get super-frustrated in short order by having to wait 60-90 mins for the spa to heat up.
 

Newdude

Well-known member
Jun 16, 2019
1,909
NY
. I have found that when school starts up, pool use drops off like a stone .... and school starts in mid-August here in Tucson!!! So I wind up maintaining a swimmable pool for months with very little use (weekends only).
And weekend only use rarely pans out either :
Saturday has 2 games to go to in the morning, it rains Saturday afternoon /Evening and Sunday is a Christening 3 hours away.