Heat pump, Good Idea?

[Sideshow Bob]

Man o man I am having a bad day in expressing myself. I meant the running cost

Sorry. Consumption is 2kw per hour so it would depend on how long you run it for. I think ours is set from 8 to 5. If it reaches max (31 degree), it sets itself off apparently. I didn't check if it does or not.

*waits for someone (not you) to educate me about how I got my kw and kwh and kWh wrong..

 

[Mike Hoxbig]

Sorry. Consumption is 2kw per hour so it would depend on how long you run it for. I think ours is set from 8 to 5. If it reaches max (31 degree), it sets itself off apparently. I didn't check if it does or not.

*waits for someone (not you) to educate me about how I got my kw and kwh and kWh wrong..

No need to, the light bulb will now go off itself - how many kw per minute?

 

[Sideshow Bob]

Just to add my 2c. Pool cover helps a lot in retaining the heat. I was lazy and didn't put it on for 3-4 days (and nights) and it probably dropped 4-5 degrees despite heat pump as son complained a bit. Temp was fine for me. It rained overnight once so that also didn't help.

 

[Sideshow Bob]

No need to, the light bulb will now go off itself - how many kw per minute?

listen, you....wena... I haven't eaten since my breakfast pizza so you better behave..

 

[RonSwanson]

Man o man I am having a bad day in expressing myself. I meant the running cost

Running costs are around 30% of a normal resistive heater geyser element.
Every heat pump has a COP, or Coefficient of Performance.

Understanding COP: Coefficient Of Performance Of Heat Pumps

COP of heat pump is calculated by dividing useful heat (or cold) an HVAC device will produce if we give it certain energy input . The highest COP heap pump can achieve is more than 20 (theoretically).

learnmetrics.com

 

[leon.davibe]

Sorry. Consumption is 2kw per hour so it would depend on how long you run it for. I think ours is set from 8 to 5. If it reaches max (31 degree), it sets itself off apparently. I didn't check if it does or not.

*waits for someone (not you) to educate me about how I got my kw and kwh and kWh wrong..

Yea pool heat pump switches off once to temp and switches on x below temp again

Unless it is inverter model

Then it tapers down heat output to sustain temp once it drops temp output increases again (power consumption changes with this)

They normally also have a flow sensor and switches off once pump goes off and back on when pump runs again

(It stays on ie powered but normally show flow error and thus heating/fan switch off )

Reversed "3"03 on display when the case

 

[leon.davibe]

Running costs are around 30% of a normal resistive heater geyser element.
Every heat pump has a COP, or Coefficient of Performance.

Understanding COP: Coefficient Of Performance Of Heat Pumps

COP of heat pump is calculated by dividing useful heat (or cold) an HVAC device will produce if we give it certain energy input . The highest COP heap pump can achieve is more than 20 (theoretically).

learnmetrics.com

And this value is affected by other factors like ambient temp etc

So not a constant

Though the power usage will probably stay constant the heating effect won't

 

[RonSwanson]

And this value is affected by other factors like ambient temp etc

So not a constant

Yes, in the same way that it affects a resistive water heater. Not sure what point you are trying to make.

 

[leon.davibe]

Yes, in the same way that it affects a resistive water heater. Not sure what point you are trying to make.

Just trying to say the ratio between energy consumption and heating output isn't a constant.

ie if running overnight to get pool up to temp you wont get the same cop in the night vs the day. And naturally hot/cold days

 

[RonSwanson]

Just trying to say the ratio between energy consumption and heating output isn't a constant.

ie if running overnight to get pool up to temp you wont get the same cop in the night vs the day. And naturally hot/cold days

Yet the condition you describe affects any hot water appliance, not only heat pumps, so in the general principle of a heat pump having a CoP between 2.9 and 3.5 over that of a resistive element having a CoP of 1, is still valid.

 

[leon.davibe]

Yet the condition you describe affects any hot water appliance, not only heat pumps, so in the general principle of a heat pump having a CoP between 2.9 and 3.5 over that of a resistive element having a CoP of 1, is still valid.

yea for pool heating it is the only electrical form that is viable

have heard of people with over 25k bills because of jacuzzi with electric elements
heating water with a heat pump vs resistive is a no brainer , the savings is substantial

naturally you have to make back the initial layout , the bigger the family or bigger the quanity of water you heat the quicker the roi

in the case of the guys with the jacuzzi it would be a month or two, naturally i don't know what portion the jacuzzi made up , just thumb sucking

 

[longboy]

Yeah, installed heat pump - works off solar mostly but is on non-essential so it stops during LS - will consider putting it on essential soon. Also, I think once I get prepaid meter, it should cost me less than R100 for electricity per month.

Currently temperature is lovely to swim - 29-31 degrees and curious to see what happens in winter.

I keep it at 40 C. It chows electricity faster than a minister on a bucket of KFC though once you go above 30 C. Plus side is it's wonderful for winter.

 

[Sideshow Bob]

I keep it at 40 C. It chows electricity faster than a minister on a bucket of KFC though once you go above 30 C. Plus side is it's wonderful for winter.

Wow, 40C even now ? Or only during peak winter ? Does it really reach 40C though ?

 

[longboy]

Wow, 40C even now ? Or only during peak winter ? Does it really reach 40C though ?

It peaks close to like 39 C at winter ja.

 

[leon.davibe]

It peaks close to like 39 C at winter ja.

Pool size vs heatpump output ratio probably plays a role and the blanket helps retain heat to a point

The bigger the pool the harder / more expensive it becomes to be able to do that

 

[Sideshow Bob]

Pool size vs heatpump output ratio probably plays a role and the blanket helps retain heat to a point

The bigger the pool the harder / more expensive it becomes to be able to do that

So, we don't have pool blanket but pool cover like this. This definitely helps. Whenever I don't close it and leave pool open, temp drops overnight significantly (would say 3-4 degrees at least? didn't measure though) and worse obviously if it rains overnight.

 

[DrJohnZoidberg]

Anyone seen these Deye heat pump water heaters around?

Hybrid AC/DC Solar Air Source Water Heater Manufacturers, Suppliers, Factory

Zhejiang Deye HVAC Technology Co., Ltd. is China solar air source water heater manufacturers and suppliers, our factory wholesale solar air source water heater(hybrid AC/DC).

www.deyesolar.com

I see a few local sites but they all look scammy. Doesn't look like Heroldts has these and I think they are an official Deye stockist.

 

[leon.davibe]

Anyone seen these Deye heat pump water heaters around?

Hybrid AC/DC Solar Air Source Water Heater Manufacturers, Suppliers, Factory

Zhejiang Deye HVAC Technology Co., Ltd. is China solar air source water heater manufacturers and suppliers, our factory wholesale solar air source water heater(hybrid AC/DC).

www.deyesolar.com

I see a few local sites but they all look scammy. Doesn't look like Heroldts has these and I think they are an official Deye stockist.

Kinda silly imo

Why build an island
Makes more sense to buy a normal AC heatpump and buy some more panels for normal solar setup

Cause then the extra solar power can go where you want to use it kettle aircon whatever

Instead of heating the pool only

if a big pool verry unlikely to heat in winter so panels only work a few warm months idle the other 8 months?

Edit : These island systems only make sense if you don't want to do a solar setup and only want solar savings on this one area

 

[DrJohnZoidberg]

Kinda silly imo

Why build an island
Makes more sense to buy a normal AC heatpump and buy some more panels for normal solar setup

Cause then the extra solar power can go where you want to use it kettle aircon whatever

Instead of heating the pool only

if a big pool verry unlikely to heat in winter so panels only work a few warm months idle the other 8 months?

Edit : These island systems only make sense if you don't want to do a solar setup and only want solar savings on this one area

AFAICT you don't need to use the PV inputs, you can just power it from AC which is already solar generation on my side.

It also can be useful having an independent system like this that allows you to directly connect PV panels, for instance in my situation I'm already running close to the maximum PV for my MPPTs and no longer have any space left on the roof close to the inverter. It would actually be quite convenient and cheap for me adding 3 or 4 panels to this unit.

My main goal here is finding a good quality hot water heat pump system that is designed to be outside and that I can control locally through home assistant. I think these Deye units just use Tuya compatible software.

 

[wingnut771]

AFAICT you don't need to use the PV inputs, you can just power it from AC which is already solar generation on my side.

It also can be useful having an independent system like this that allows you to directly connect PV panels, for instance in my situation I'm already running close to the maximum PV for my MPPTs and no longer have any space left on the roof close to the inverter. It would actually be quite convenient and cheap for me adding 3 or 4 panels to this unit.

My main goal here is finding a good quality hot water heat pump system that is designed to be outside and that I can control locally through home assistant. I think these Deye units just use Tuya compatible software.

How is that any different from this?


It wont be cheap once you see the price for the Deye if you can get one.