Gas heater vs heat pump--which one do I pick????

[PoolGate]

^ This unit is really expensive. I am in the design stage for a new small fiberglass pool and thought about it briefly, but it doesn't make a lot of financial sense to me.

I ran some numbers for both natural gas and a heat pump in my location. Theoretically I would save a little on operating costs with the heat pump, a 3-4 year payback period at my pool installer's prices (they charge about $2K less for a gas heater). But I realized that in the shoulder seasons I'm not going to be swimming on weekday evenings, so will likely only fire up the heater on a nice weekend day rather than running it continuously as the calculators assume - that's behavior that's more consistent with a gas heater, and means the savings from a heat pump would likely be even less. I decided to go with gas.

Believe me that $2k will be eaten up by the cost to run the gas line.

Having a gas heater I am finding myself kind of wishing I had gone with a heat pump. The gas costs us @ $1400/year to run on an on-demand basis. I am not really sure what the heat pump would cost. But my neighbor's pool (heat pump) is always over 90. He says he is under $50/month in electric for the heat pump. Mine dropped into the 70s the other night because I was not running the gas heater for 2 days. I will not use the solar cover it is just too much bother for me. We also did not swim beyond labor day last year. It was just too cold out of the water. So extending the season sounds better in theory than in practice. We did open early, however. Really, if I could find a cheap used heat pump I would add it to my system. It would be really nice to have both.

 

[Newdude]

My buddy has a Full service gas company. He keeps trying to convince me to have both. The electric is more expensive here than the gas but the gas heater goes through so much that it all pretty much levels out. And who knows which will be cheaper a few years from now with both markets pretty volatile and subject to swing.

 

[domshort]

Well, we ended up with gas and I have to say that I appreciate the on demand heat since our schedules and weather is very inconsistent. However, I am a bit nervous to run the heat as much as I'd like without any idea of the daily cost. Does anyone know how to figure out how many btu's the Pentair mastertemp 300 natural gas uses per hour? If i have this information, I can convert the btus to cubic feet and calculate a per hour cost. Thanks in advance!

On a side note, having both sounds amazing...always the best to have options especially with the volatile markets as @Newdude stated.

 

[PoolGate]

Well, we ended up with gas and I have to say that I appreciate the on demand heat since our schedules and weather is very inconsistent. However, I am a bit nervous to run the heat as much as I'd like without any idea of the daily cost. Does anyone know how to figure out how many btu's the Pentair mastertemp 300 natural gas uses per hour? If i have this information, I can convert the btus to cubic feet and calculate a per hour cost. Thanks in advance!

On a side note, having both sounds amazing...always the best to have options especially with the volatile markets as @Newdude stated.

Since it is a 300k btu heater, that is 300k btu/hour which is roughly 3 therms/hour.

Also why didn't you go with a 400k btu unit? If you get a sec please fill out your sigline! https://www.troublefreepool.com/account/signature

 

[ajw22]

Does anyone know how to figure out how many btu's the Pentair mastertemp 300 natural gas uses per hour? If i have this information, I can convert the btus to cubic feet and calculate a per hour cost. Thanks in advance!

A 300,000 BTU heater uses 300,000 BTUs/hour.

 

[domshort]

Thanks... so looking at about $3/hr in my area. I'll surely pay around $10/day for a warm pool

 

[ajw22]

Thanks... so looking at about $3/hr in my area. I'll surely pay around $10/day for a warm pool

How many gallons in your pool?

It would be helpful to us to have the details of your pool in your signature.

 

[domshort]

Went with the 300k per my pool contractor recommendation. We have a 22k gallon pool. I will definitely work on the sigline, I'm new to the site and just trying to navigate. We waited all summer for this pool we finally got complete and it honestly reminds me of having a newborn...lots of initial work and very little instruction.

 

[ajw22]

Your 300K heater will heat your 22,000 gallon (183,000 lbs) pool about 1.3 degrees an hour.

Your pool contractor didn't do you any favors recommending a 300K heater. A 400K heater would give you about 1.7 degrees an hour.

 

[PoolGate]

Thanks... so looking at about $3/hr in my area. I'll surely pay around $10/day for a warm pool

$10/day will give you about 3 degrees in temp. Maybe 4-5 on a sunny day. When I run my heater in cooler temps (70s-82ish) I get 1-2 degrees per hour or so. I usually start the heater at 8am and it is up to 88 by 2-3pm. I then run the heater the entire time we are swimming. Meaning when I "need" the heater, it is on for roughly 10 hours a day. For me that is around $45/day. My heater is 400k btu. I think you will need to run the heater a lot more than you are thinking.

 

[domshort]

Currently I have been averaging a 2 degree increase/hr. Thats with temps in the 60's/night, low to mid 70's day. Our pool is a southern exposure with few trees so we obviously get help from the sun. I plan on adding a solar cover next year when I have time to fabricate the DIY reels. This season I'm just focusing on getting the chemicals balanced of which my pool guy was little help. He looked at me strange when I asked about CYA level.