After much deliberation, I finally decided to get a heat pump installed for my hot water needs. The other alternative was a gas geyser, however i decided i did not want to be reliant on gas for hot water. 

Having a 5.4kw unit put in. I want to gauge its performance with winter on its way, and if it is inline with expectation, i plan on moving it onto essential loads. My pv system should have enough power to run it during the day. After discussing with the supplier, the representative suggested that the smaller 3.6kw unit would be a better fit for my current reality and expectation, i opted for the bigger size though for the incase factor.. ie.. in case i decide i want a second geyser hooker up..  or in case in the future i upscale from 150l to 200l etc..

That and given the math.. power wise it should use about the same power regardless. It should have a nominal power draw of some 1300w, so hopefully i see a material difference in electricity useage. Will post some results in 2 months odd time when the useage cycles cycle through

2 minutes ago, GTP said:

After much deliberation, I finally decided to get a heat pump installed for my hot water needs. The other alternative was a gas geyser, however i decided i did not want to be reliant on gas for hot water. 

Having a 5.4kw unit put in. I want to gauge its performance with winter on its way, and if it is inline with expectation, i plan on moving it onto essential loads. My pv system should have enough power to run it during the day. After discussing with the supplier, the representative suggested that the smaller 3.6kw unit would be a better fit for my current reality and expectation, i opted for the bigger size though for the incase factor.. ie.. in case i decide i want a second geyser hooker up..  or in case in the future i upscale from 150l to 200l etc..

That and given the math.. power wise it should use about the same power regardless. It should have a nominal power draw of some 1300w, so hopefully i see a material difference in electricity useage. Will post some results in 2 months odd time when the useage cycles cycle through

nice one..

i had a 3.2Kw heat pump hooked up to a 200L geyser, in summer all was good, but the moment winter/cold weather came around it would take about 2 hours to heat the water to 60 degrees.

So last May i changed to a 7.2Kw heat pump with the same 200L geyser, and havent looked back since. In summer to heat the water to 60 degrees is approx 35 mins, in winter it takes about 55 mins max..i know there are other factors that influence the time it takes to heat the water, but this is based on actual experience..

That certainly makes me feel better about going with a bigger unit 😀

Given the orientation of my house, the only viable location i had was a west facing wall. Will only see sun during the afternoons, so i was also weary of winter performance with a smaller unit

8 minutes ago, GTP said:

That certainly makes me feel better about going with a bigger unit 😀

Given the orientation of my house, the only viable location i had was a west facing wall. Will only see sun during the afternoons, so i was also weary of winter performance with a smaller unit

what make of heatpump did u go with? 

i have an alliance heatpump, just wish they had a "smart" control panel so i can integrate it with HA. The standard control panel is very "limited" in terms of functionality.

 

23 hours ago, Iiceman said:

what make of heatpump did u go with? 

i have an alliance heatpump, just wish they had a "smart" control panel so i can integrate it with HA. The standard control panel is very "limited" in terms of functionality.

 

I went with an ITS branded heat pump. I had some good discussions with them. I heard similar about the control panel being rather simple. It sounds like it does what i need it to though in terms of timers etc. The tech was telling me the units actually use more power when on timers. At this point it doesnt matter, but when it goes on essential loads i definitely dont want it on at night

Edited March 8, 20224 yr by GTP
Typos

22 hours ago, GTP said:

That certainly makes me feel better about going with a bigger unit 😀

Given the orientation of my house, the only viable location i had was a west facing wall. Will only see sun during the afternoons, so i was also weary of winter performance with a smaller unit

A heatpump uses a large volume of air to extract the heat, it makes very little difference if it gets any sun. If the air around it is nice and warm it will run for shorter times (and use less power in total) but ambient temp makes the biggest difference. I only run my ITS once a day during mid-day and it takes about 800Wh-1KWh  to heat up my 150l geyser. The important part is to install your heatpump as close as possible to your geyser. In my case the geyser is a D-Rated and loses about 2.0-2.5KWh every day but if the sun provides the power it is not too bad.

I would also opt for the bigger unit, the difference in price is not a lot and in the ideal situation you actually want a 300l B-Rated energy efficient geyser with R1 insulation over all the pipes. Cold water inflow will have very little effect on a large geyser vs small geyser.

I would be interested to know how much they charge for the installation

Edited March 8, 20224 yr by iiznh
typo

Thanks for your comment iiznh,

I agree with your point re the sun. Reason i mentioned it was because that side of the house only ever sees the sun in the afternoon, i am not clear how warm the air would be in winter time in that area. The rooms on the west side feel like fridges in winter. Operating range is between -7 to 43 odd.. so should be ok.

I did not realise there was a timer set on the unit so woke to cold water 😁. On clearing the timer the unit fired up and ran for some 45 to 50mins. Water is nice and hot again. My geyser is rated at E and loses some 2.7kwh of energy. The installers did take care to lag all the piping as well as install a blanket on the geyser.

Going to play around with it and wait to gauge winter performance before i move this all onto essential loads

 

Heat pump has been in for a little over 2 weeks now. From my observations, it runs for 30mins when the time kicks in. This is around midday. It then kicks in again with the bath/shower routines between 6 and 8pm. The latter times.. for about 15 or 20 mins. So in all. It appears to run for some 1h15 a day given the current weather and the current useage pattern. My guestimate is thus 1400w odd for hot water. 

So far so good. No noticeable difference in water temperature. Going to wait until May or June to gauge how it runs before I then move it onto essential loads. I can then also verify whether it does in fact run per spec at around 1200w. This should be easily covered by my PV which does virtually no work from 12pm currently.

My billing cycle runs from 18 to 17 of each month. So i will obly get to see its effect on total power from the next month cycle. However i am curious to see what these 10 days would have done.. for a change I am actually eager to receive the bill

3 hours ago, GTP said:

My billing cycle runs from 18 to 17 of each month. So i will obly get to see its effect on total power from the next month cycle. However i am curious to see what these 10 days would have done.. for a change I am actually eager to receive the bill

I take photos of my meters every month and submit the readings. This gives me proof of the readings and ensures that they do not bill me on a guesstimate. 

My heat pump saves about 3-4KWh per day, I am also interested in seeing how my winter consumption will change. 

 

Edited March 23, 20224 yr by iiznh

As promised, i received my power bill today. For the first ever for my household, my eskom useage dropped below 200 units. 

I averaged out my consumption between October and and Feb, and this last cycle useage turned in a 55% reduction in power use. This also coincided with the temperature dropping around these parts. The effect of the temperature changes has been that the unit runs for around 2hours a day, rather than the 1h15 i was seeing last month. 

I think I am happy with the performance so far. I expect to see bigger savings in summer when the ambient helps performance. I think i will give it another month before I move it onto essential loads. I also dropped my inverter grid feed from 20w to 10w. I dont get expect material differences from this, but every bit helps.

Now... aboiut a gas stove...

Edited May 4, 20224 yr by GTP

June bill just arrived. I noticed the heatpump runs for around 2h15 a day now with our useage. When it was installed in March it ran about 1h30. I put this down to the ambient temperature drop which has been significant this month. The extra run time has added 0.8units per day over this last billing cycle. Within expectation, and 62% less power than June 2021. 

My heatpump averaged around 1.1KWh per day (March), currently(June) using about 1.6KWh to warm the water(150l). It runs for about 90 minutes.

I have since installed solar and get great satisfaction from heating water during the day when the sun shines (still need to install a battery so grid-tied for the moment).

Thanks for all the updates. Extremely useful.

I've had a heat pump for a while now. When I went solar we took the decision to keep the heat pump on the essential loads side of the DB. 

These things come in different sizes, with different loads, but mine adds about 1.5 kw to the total load. This morning it ran for 1:45 to get the geyser up to 55 degrees. I start it again at 12:00 and it just ran for 40 minutes. I also had a blanket and lagging installed, and recent experience is that the geyser will still be above 50 degrees at 18:00.

So that's about 3.7kw/h per day, all coming from the sun (on a sunny day).

On 2022/03/07 at 10:58 AM, Iiceman said:

nice one..

i had a 3.2Kw heat pump hooked up to a 200L geyser, in summer all was good, but the moment winter/cold weather came around it would take about 2 hours to heat the water to 60 degrees.

So last May i changed to a 7.2Kw heat pump with the same 200L geyser, and havent looked back since. In summer to heat the water to 60 degrees is approx 35 mins, in winter it takes about 55 mins max..i know there are other factors that influence the time it takes to heat the water, but this is based on actual experience..

hi @Iiceman how many KWs does the 7.2kw unit pull ? I was looking at 5kw heatpump (Alliance) from AC direct they told me it uses about 1.3kw per hour which is not bad. So was wondering what the 7.2kw unit is on usage 

All good @IicemanFound it online, sharing below 

6 minutes ago, Treschen said:

All good @IicemanFound it online, sharing below 

@Treschen, those numbers are not entirely accurate, i have a sonoff pow R3 monitoring it, and it uses about 2.4Kw/h. Ive seen it jump to about 2.6Kw/h at times..

Just now, Iiceman said:

@Treschen, those numbers are not entirely accurate, i have a sonoff pow R3 monitoring it, and it uses about 2.4Kw/h. Ive seen it jump to about 2.6Kw/h at times..

Thanks @IicemanI can live with 2.6kwh vs my current 4.4kw 

Just now, Treschen said:

Thanks @IicemanI can live with 2.6kwh vs my current 4.4kw 

definitely, its a significant difference..

here is my usage graph for the last 24hrs..

 

@Iicemannot bad! Is this the Alliance unit ? Torn between this and the kwikot unit 

3 hours ago, Treschen said:

@Iicemannot bad! Is this the Alliance unit ? Torn between this and the kwikot unit 

I had a 2 day experience with a Kwikot and got it removed. 9yrs later and I am very happy with the ITS.

Not all heat pumps perform the same. I was wondering when I read a 7.2kw unit only using 1.3kw per hour?

Edited July 29, 20223 yr by Scorp007

17 hours ago, Treschen said:

@Iicemannot bad! Is this the Alliance unit ? Torn between this and the kwikot unit 

correct, its an Alliance, at the time there was no 7kw or equivalent ITS, still not sure there is..

this is my 2nd Alliance, and very happy with the overall performance

ITS have these models:

3.6, 4.5, 5.0, 5.4, 7.6 and up to 200kW. Info on their Web. The 7.6kW is currently on a great prize.

Edited July 30, 20223 yr by Scorp007

This post has me quite excited. I've recently been annoyed with my solar doing nothing from around 1pm on a hot day so was looking at perhaps installing a smaller element into my current Kwikot 200L geyser and then moving it onto essential loads, but the heat pump solution is sounding better and better as time goes by. Still quite a rookie in the solar space with today marking having it for a year. Currently have a 5kw Multiplus II. When the family isn't paying attention and starts making evening food with kettles and airfryers the load can reach about 4.3kW for a odd 5mins and I start getting emailed alarms about temperature and overload on L1, which I've always attributed to the inverting capacity of the unit. That said, under normal circumstances the house draws about 700-800W constantly so there is definitely leeway to have it start heating up the water when the batteries are full during a normal day. That combined with a smart switch I plan to run via HA would be ideal for me. Would it be ok if i were to compile a list of smaller dumb questions to get the advice of the more experienced users here? 

Surely if it is related to water heating this is the place to ask 😀