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Help: "Bigger" HeatPump or Gas Geyser upgrade


Iiceman

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Hi All
Some advice please, as i amm learning some very costly lessons..

So currently i have a 3.2kw Alliance air heat-pump, with a 200l geyser. Works great, however for a family of 4 (3 long haired females), we run out of hot water very quickly, especially in winter. In winter the heat-pump takes on average 4 hours to heat the water to 55c. With our work schedules, the wife and I need to leave home by 6am, problem is the rest of the fam dont get hot water till about 9am. Apparently the school frowns upon late comers.Who would have know. Summer is a lot better, but still an issue, cause of the heating time.

So to mitigate this issue (with  my limited knowledge) I was convinced that an Atlas 20l gas geyser(not constant temp) will be our silver bullet and sort our our issues. Heat-pump is used as backup.Gas works great except we chewing through 48kg's a month(total shower time of the fam is 60mins per day with one shower being used at a time, and gas flow\temp set to min\46c). Now my pocket is not happy , especially with the recent gas price increase.

So doing some research, and seeing that both options below are similar in price, i think without making too many changes, i have 2 options: 

1- Changing my "regular" gas geyser to a constant temp gas geyser. Apparently is uses a lot less gas then a diaphragm/regular gas geyser,  and we can use more than one shower at a time. Heat-pump will remain as a backup.

2- Changing my heat-pump to a "larger" heat-pump, like a 7kw version. Water will be heated twice as fast than current one. Also its running costs is low, and gas geyser can remain as backup.

Here is where i need advice/help...
1- Does a constant temp gas geyser use less gas than a regular gas geyser? Which are the better gas geyser brands i could look at?

2- Would a bigger heat-pump be a better fit for this situation instead of gas? Alliance Air heat-pump or ITS heat-pump?

Thanks for your time..

Iceman
 

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Gas does cost more to heat the water. Even the most efficient gas geyser is still going to eat at your pocket.

I have a 3rd option for you. Change your shower heads to reduce your water usage. This is such a cheap option and easy to do (around R100/shower), that I would recommend you try it. If it does not work for you put back the old heads and go for one of your more expensive options.

The amount of water used by these modern eco shower heads are large. Something like this that you can get at any hardware store.
https://www.builders.co.za/Bathroom/Showers-%26-Shower-Accessories/Shower-Rose-%26-Hand-Showers/Builders-Chrome-Plated-Shower-Rose/p/000000000000024162

We are also a family of 4 (2+2) and everyone has warm water with plenty to spare (for when you get visitors). 150L geyser with 3.4kW heatpump. HP is set to heat water to 55 for 6am and 3pm.

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17 minutes ago, Louisvdw said:

Gas does cost more to heat the water. Even the most efficient gas geyser is still going to eat at your pocket.

I have a 3rd option for you. Change your shower heads to reduce your water usage. This is such a cheap option and easy to do (around R100/shower), that I would recommend you try it. If it does not work for you put back the old heads and go for one of your more expensive options.

The amount of water used by these modern eco shower heads are large. Something like this that you can get at any hardware store.
https://www.builders.co.za/Bathroom/Showers-%26-Shower-Accessories/Shower-Rose-%26-Hand-Showers/Builders-Chrome-Plated-Shower-Rose/p/000000000000024162

We are also a family of 4 (2+2) and everyone has warm water with plenty to spare (for when you get visitors). 150L geyser with 3.4kW heatpump. HP is set to heat water to 55 for 6am and 3pm.

Hi Louis

Thanks for the suggestion, i have tried the eco shower heads, however because my wife and i shower lets say 2 ours before the rest of the fam, the remaining water in the geyser gets cold before they can shower, which then in turn requires another heat cycle, which in winter can take 4 hours or so.

Edited by Iiceman
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I personally would go for a bigger heat pump. I have a gas geyser for the past 4/5 years and after replacing 2 of them and various other niggles have decided to upgrade to a heat pump. I have read good reviews on the ITS brand and will probably go for the 5.6kW.

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7 minutes ago, GVC said:

I personally would go for a bigger heat pump. I have a gas geyser for the past 4/5 years and after replacing 2 of them and various other niggles have decided to upgrade to a heat pump. I have read good reviews on the ITS brand and will probably go for the 5.6kW.

yeah the more i research it now, the more i discover that gas geysers in general have a higher running cost. I guess thats the price of convenience. Also seen the ITS brand has good reviews, will def be checking them out.. 

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21 hours ago, Iiceman said:

Alliance Air heat-pump or ITS heat-pump

My Experience with alliance is that you would struggle to get spares, even the people who installed it could not supply spares 3 years after installation, so it became my problem to source it. 

15 hours ago, midnightcaller said:

ITS , Alliance or Kwikot.

Let me tell you something that I have learned from ITS, I have not asked the Owner or any employee of ITS permission to publish this here, nor am I involved in ITS at all except for buying, reselling and installing their products.

When I did my accreditation training with them the owner (Refrigeration Engineer) told us a very interesting story and here it goes in my words.  

Back in about 2007-2008 he went to China to choose an off the shelve heat pump like all other makes mentioned in this thread and other threads in this forum. After visiting many manufacturers he chose the best unit he could find , brought one back to SA and then hired and Retired Regeneration Field engineer from the UK for a couple of weeks and together they looked at the common parts that normally packs up and reverse engineered the unit. They then went and sourced  more reliable parts for the ones prone to fail and went back to the manufacturer and made a deal that the units be changed to his design and parts replaced with his speck. The ITS series is now still manufactured there but only for ITS. 

Any other company can still choose from the shelve items and have them re-branded and when you look at some of the other units you will see its exactly the same units, just re-branded for the specific company. ITS looks completely different, and they they use non metallic body's to eliminate rust in coastal areas. 

Riaan H (The owner) also developed his own mixture of refrigerant to make some of the units more efficient and allow some of his models to reach 70degr C on the outlet gas side vs the 60deg c industry standard for residential heat pumps. 

When I ask him why he claims Lower COP ratings than the competition, he bluntly stated that he would rather under promise and over perform, than mislead the customers. He takes the COP he can expect in the coldest areas of SA and rate his units accordingly. This means that I the warmer areas the units offer a much higher COP. 

Lastly they also have a unique circulation system, where the water gets circulated and heated at the unit first before its allowed to circulate to the geyser. This allow heating of the water at much lower ambient temperatures than most of the competition. 

The 5.0kw Super is a monster unit and capable of delivering 70deg water. 

And off coarse they have local back in CT and Pretoria

21 hours ago, Iiceman said:

2- Would a bigger heat-pump be a better fit for this situation instead of gas? Alliance Air heat-pump or ITS heat-pump?

Is it an old geyser, inside or outside. 

Geyser blankets might help reduce the standing heat loss, but unfortunately for early morning heating a bigger Heat-pump will be needed. 

Lastly, can you please take a picture of your current installation (specifically focusing on where the return pipe of your heat-pump enters your geyser) ,running out of hot water quickly on a 200 lt geyser does not make sense. you might be having an installation issue where the incoming water is stirring your water in the geyser mixing hot and cold causing the hot water that should be on top, to be cooled down to fast. 

 

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22 hours ago, Iiceman said:

i have 2 options: 

another option would be to increase the hot water storage size. It might be possible to just add a second 200l geyser in parallel to the existing installation. This would also allow you to run the heat pump in a more economical range (less cycling and lower supply temperature)

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2 hours ago, Fuenkli said:

another option would be to increase the hot water storage size. It might be possible to just add a second 200l geyser in parallel to the existing installation. This would also allow you to run the heat pump in a more economical range (less cycling and lower supply temperature)

Or swop the storage for a smaller size that will heat up faster. This should use less power and should be cheaper to buy

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I just had an ITS heat pump installed. The 5kw Super (1.25kw usage). Here are my thoughts.

I have 4.8kw of solar panels, a 4.6kw goodwe inverter and 7kw of lithium batteries.

Before my heat pump upgrade I had a 2kw element in my 200L kwikot. I'm still not sure I should have bought the heat pump, the 2kw element took +-2.5 hours in the morning to heat up the geyser, so 5.0kw, where this does it in 1 hour for about 1.6kw. I've also had my geyser replaced with a more efficient one, so maybe the water is just hotter in the morning anyway.

The heat pump is one extra thing that can break and R1000 a year for a mandatory warranty tied maintenance checkup. R25,000 for the unit with installation.

The only benefit to me is having warmer water faster in the mornings and maybe putting away more energy into my battery banks on a cloudy day.

I doubt I would buy one again (Solar water geyser was out due to placement and orientation), haven't lived with long enough to decide yet...

This is the ITS's power usage in the morning. It starts off at 9am with +- its rated 1.25kw but there is a huge spike at the end of its cycle. Anyone else seeing this ?

image.png.bd7adc1f2cc63d00c57f56cd1f435a6b.png

Here is my previous 2kw kwikot running on a good day from 11:30 to +- 2pm

SIYKzaZEuGcp0DfTSrW0IW_ZBp1D7YAonpRPbTA1Wde3P2GmlDuUlnbGsAWuHyWeHwjFkd9j6iAyl4I_qP9aDNCjPrglTlwxlV8MdMAVafbZrReRuVrl90hW2sfXwL-Ms_NkKO00cdM

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4 hours ago, Reyn said:

The heat pump is one extra thing that can break and R1000 a year for a mandatory warranty tied maintenance checkup. R25,000 for the unit with installation.

The only benefit to me is having warmer water faster in the mornings and maybe putting away more energy into my battery banks on a cloudy day.

I doubt I would buy one again (Solar water geyser was out due to placement and orientation), haven't lived with long enough to decide yet...

Solar water heating would only be beneficial for evening hot water so this isn't a total solution.

So you need some way to heat water in the morning. The heat pump is way more efficient than an electric element.  (3x maybe more??)

You need to run the calcs and see your ROI..

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In my case my 2kw geyser was already using free solar energy.

I thought I'd give my inverter a break, which I am, I'm not exporting power to the grid like in my graph anymore due to my prepaid meter running forward whether I buy or sell.

I spent R25k + 1k a year to have an additional piece of equipment that can break.

The only benefit is that I can wash dishes at 9am instead of 12am.

In terms of ROI, it will never pay itself back.

Sound like a bigger heat pump will solve the original poster's problems though...

 

 

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