New Heat Pump - Is my power bill about to quadruple!?

[heygreene]

Hi All,

I have a 24ft round AGP, with a 2-speed Hayward Powerflo Matrix 1HP pump. I just bought a Hayward HP50TA (50k BTU) heat pump and hooked it up on Sunday. My water was at 72 degrees 4 days ago, and now it's at around 85 degrees, which we want it at 87. I cut the pump off the first night, but lost too much heat so now I'm just letting it run to see if it will get to a point where it cuts on and off (I haven't seen this yet).

During these 4 days, my smart power meter showed me using FOUR TIMES as much electricity as just the pool pump alone. Is this normal??? I mean it's running 24hrs a day right now just getting up to temp, but I'm really hoping it will start cutting on and off soon, or I'm going to go broke.

Also, I'm running the pump on low 24hrs a day, and the heater isn't having any "flow" problems. Does the heater produce more heat with the pool pump on high?

Thanks!
Heygreene

 

[mknauss]

Do you have a cover on the pool? If not, you are in for a big surprise --------

 

[heygreene]

I do not... to be honest with you I bought the heat pump hoping to never pull that wretched thing out again... but apparently I'm in for a big surprise! And not a good one.

I only lose around 3 degrees at night, so my thought was I'm willing to pay to raise the temp 3 degrees during the day... but this thing just seems to run and run and never stop.

 

[heygreene]

For more info we want the water at 87 degrees. During the day it's around 80 degrees outside, and at night it gets to around 55 or 60 degrees.

 

[mknauss]

I am surprised you only lose 3 degrees at night, is that with the heat pump running all night or not?

 

[mknauss]

From Inyo Pools website:
You can figure about 5,000 watts or 5 kilowatts per hour per 100,000 BTU’s for a heat pump. For a typical 100,000 BTU heat pump, that’s 5 kilowatts per hour.
So for yours , appears to be maybe about 3 kw per hour running. Depending on your electrical rate, may not be crazy.

 

[mknauss]

Your 2HP pump will pull about 2kw per hour.

 

[JamesW]

I get about 2714 watts. So, every hour, that's 2.7 kilowatt-hours.

As the water temperature goes up, the heat loss will increase.

At night, with low air temperatures and low humidity, you might lose more than you gain.

Evaporation removes a lot of heat.

And, the heat pump performance drops as the air temperature decreases.

If we assume running continuously 24 hours a day for a month at 10 cents per kilowatthour, that's about $194 for the month.

 

[ajw22]

I have a 24ft round AGP, with a 2-speed Hayward Powerflo Matrix 1HP pump. I just bought a Hayward HP50TA (50k BTU) heat pump and hooked it up on Sunday. My water was at 72 degrees 4 days ago, and now it's at around 85 degrees, which we want it at 87. I cut the pump off the first night, but lost too much heat so now I'm just letting it run to see if it will get to a point where it cuts on and off (I haven't seen this yet).

As long as the pool temperature is above the air temperature I think you will find the HP running most of the time if you don't use a pool cover.

Maintaining heat in an AGP is tougher because you don’t have the ground insulating the sides of the pool and lose heat there as well as the top.

Also, I'm running the pump on low 24hrs a day, and the heater isn't having any "flow" problems. Does the heater produce more heat with the pool pump on high?

No, as long as water flow is sufficient for the pressure switch in the HP the amount of heat produced does not vary with water flow.

 

[Adamphotoman]

I am up in Canada just north of Maine. I learned quickly that a solar cover is absolutely a good $ saving investment. Our temperatures are not as warm as yours, so I developed my own process.

First I do cover the pool even if it is a pain to do so. I uncover the pool late afternoon to swim.
Then I only run the heater until nightfall. I would turn the system back on around 10:00 am once the day warmed up. The pool gained more heat in a shorter time that way.
I inherited the pool when we bought the house. Whoever designed the layout did a very good job.
The Heat Pump sits in the sunshine for most of the day which turns out to be the best place for it.
With my old Super pump 1 H single speed I would only also run it during the day with the solar cover on.
I found that running the circ pump at night actually promoted cooling the pool, and the Heat Pump would need to run all night just to maintain.
Actually we swim in the late afternoon so I turn it off while swimming. I would rather listen to music than the fan and compressor.

 

[heygreene]

@mknauss I lose around 3 degrees with the pump and heater off. If the heater is running, it maintains the temperature overnight, and doesn't gain or lose. I have a 1hp pump, so it will likely be a little lower on the KWH.

@JamesW thanks for the math. My actual HP uses 2.4KWH, and my pricing is 10.77 cents per KWH, so you were pretty much dead on (I came up with $192). I know it won't run 24x7 all the time, so hopefully I won't get TOO much sticker shock once I get my bill. If so, I guess I'll pull the old cover back out. Also my 1hp 2-speed pump on low uses .27kwh, so running 24x7x31 days in a month is only $19, so hopefully that won't hurt things too much.

 

[heygreene]

@Adamphotoman thanks for the tips! I am thinking of doing the same thing... having the pump and heater only run during the day, starting at around 9am or so, and cutting off some time in the afternoon. I am seeing the same thing you are... when the temperature dips, the HP can run for 10hrs overnight just to keep the temperature the SAME (no increase in heat). However, during the day when it warms up into the 80s I can get about a 1 - 1.5 degree increase every couple of hours. I'm still going to try to avoid using the cover, but it may be a losing battle!

 

[mknauss]

I have a 1hp pump, so it will likely be a little lower on the KWH.

Ok. Check your signature. Says 2hp 1sp pump

 

[Adamphotoman]

I found I lost a lot of heat if I didn't use the solar cover. Think wind, evaporation, and colder night time temp. In some areas, such as Ontario, the electrical is tiered. Meaning it costs more during peak demand times, and it cost less at night and on weekends.
There are problems associated with only using the cheaper rates though.
If the solar cover is used during the day without the pump on, it could raise the temp only at the surface. My brother in law adopted this approach and ended up fighting algae. The top 6 inches or so became a great breeding ground - without the pump mixing it up. Also those warmer temps will degrade the solar cover.

 

[heygreene]

Ok. Check your signature. Says 2hp 1sp pump

Thanks, I updated it!

 

[heygreene]

What are the thoughts on liquid solar blankets, and will they be safe with my HP?

Last night I lost 3 degrees with the HP running the entire time! Normally it at least keeps the temperature stable if it runs all night. Got a little cooler last night, maybe 50.

 

[Pool_Medic]

Liquid solar works, if you have zero wind, in other words it works great on indoor pools and will stop condensation from forming on windows.

For outdoor pools it is useless. If heat retention is your goal, look up thermal blankets, expensive yes, but nothing matches them.

 

[sktn77a]

OP: If you cut your solar blanket into 4 quarters, it will be much easier to manage - just float each of the four pieces to cover the pool like it was before you cut it. You won't significantly impair the insulation or evaporation prevention.

 

[heygreene]

OK so the pool heater is now working pretty effectively now that the weather is in the 80s during the day. We have the thermostat set at 87, and it stays cut off almost all day long, and only cuts on in the evening through the morning as needed. I was originally using around 1.5 - 2kwh power before I installed the heater. I peaked around 6kwh daily when the heater was first turned on and running 24x7. Now I'm averaging around 4kwh, so I will likely maybe double my power bill, plus it's getting warmer out so I also have to take into consideration that the HVAC unit on the house is also running. All in all, I feel like just leaving it running all the time with my pump on low (costs less than $20/month) seems to be the best bet, so the heater can kick in when needed.

As for covering it... I've been using my solar blanket (cut into 3 sections) most nights, but I'm going to do some testing without covering it for the next few days and see how it does. I believe the pump can catch back up to the temperature fairly quickly if it's warm out, but at first glance it looks like I'm losing a LOT of water to evaporation. I mean like I'm adding water a couple of times a week at a minimum. I'll report back, thanks!

 

[heygreene]

OK I'm a believer in the cover now... last night the pool started at 87 and ended at 84 this morning with the cover off and the heater ON all night. So it lost 3 degrees while the heater ran all night. The other problem is it's still running at 11:30am, and it's over 75 degrees outside, so there's a LOT of catching up it has to do.

Everyone said it, now I believe it... I'll be using the cover nightly going forward, whenever possible.

One other side note some folks may find interesting: The heater didn't seem to be heating very well until I leveled it. I noticed the makeshift "pad" i had created to sit the heater on wasn't level. Once I leveled it,the heater seemed to work more efficiently.