June 10, 20242 yr Author On 2024/06/05 at 9:21 PM, GreenFields said: Just my 2c, going out on a limb again. To be checked. I seem to recall somewhere in a different thread you were speaking of multiple aircons to be used, maybe a 36000btu or whatever aircon by day, and 3x18000btu at night, but you had a 40A grid supply limit in the complex. Is this correct, is it the same house? Because given those figures, I wouldn't go for 3kW or so electrical elements on top of the other loads, whether it's running off PV, or even as backup elements to evacuated tubes, if you could most reasonably/sensibly/legally(?) only fit an inverter of up to a 8kW. If so, suggestion would be to look into a 3.6kW heat pump like the ITS model, but shop around anyway. Point is, it will consume less than 1kW by itself, and still generate effectively 3.6kW of heating capacity that you could connect to a geyser of up to 200l. I think in your hot climate with regularly higher ambient temps, and generally low usage of water, you could get away with a setup like this. @GreenFields - thanks for the details! Yes, we are limited by the 40A grid. I still need to see what inverter size we can run with that limitation. 1. I think you're right about the heatpump and the inverter size limitation. We do want to run multiple aircons in the evening to cool the house down (4 in total 12 BTU each). Then we'd like to run one in the lounge in the afternoon (24 BTU), so need to plan for this.
June 10, 20242 yr Author On 2024/06/06 at 9:32 AM, Bobster. said: Here's my system so far this morning. Yellow trace is load. You can see the heat pump kick in about 6:30. Total load about 1.5 kW, this includes the house "ticking over", which is 200 to 300W, so the pump is drawing ± 1.3 kW. Thanks for this! It's great to have some real world data to backup what everyone is saying! I appreciate you taking the time to contribute this!
June 12, 20242 yr Morning, My advice would be On 2024/06/10 at 8:03 AM, AlexanderR said: Thanks for this! It's great to have some real world data to backup what everyone is saying! I appreciate you taking the time to contribute this! Morning, my advice on this if you is if you have the budget install solar geyser as your primary source of heating and have the heat pump as your auxiliary back up. In the warmer months of the year your solar will 90 % of the work and in winter when the sun is weaker the heat pump will pick up the slack.
June 12, 20242 yr 2 hours ago, ITS Heat Pumps - Darrel said: Morning, My advice would be Morning, my advice on this if you is if you have the budget install solar geyser as your primary source of heating and have the heat pump as your auxiliary back up. In the warmer months of the year your solar will 90 % of the work and in winter when the sun is weaker the heat pump will pick up the slack. Just a question. The older than 10yrs ITS 4.7kW heat pumps used a inverter type motor. Are there any of the current household units fitted with the inverter motor.
June 17, 20242 yr On 2024/05/27 at 4:33 AM, AlexanderR said: What would you guys go for? Heat pump for sure.
June 17, 20241 yr Author On 2024/06/05 at 9:21 PM, GreenFields said: Just my 2c, going out on a limb again. To be checked. I seem to recall somewhere in a different thread you were speaking of multiple aircons to be used, maybe a 36000btu or whatever aircon by day, and 3x18000btu at night, but you had a 40A grid supply limit in the complex. Is this correct, is it the same house? Because given those figures, I wouldn't go for 3kW or so electrical elements on top of the other loads, whether it's running off PV, or even as backup elements to evacuated tubes, if you could most reasonably/sensibly/legally(?) only fit an inverter of up to a 8kW. If so, suggestion would be to look into a 3.6kW heat pump like the ITS model, but shop around anyway. Point is, it will consume less than 1kW by itself, and still generate effectively 3.6kW of heating capacity that you could connect to a geyser of up to 200l. I think in your hot climate with regularly higher ambient temps, and generally low usage of water, you could get away with a setup like this. I've done a lot more reading of people's opinions! 1) Since we live here year round and it's warm, would you recommend a solar geyser? 2) Any particular brands/companies? 3) If the 3 bathrooms are on 3 different sides of the house, how would you do solar geysers? - would you have 3 solar geysers or would you have 2 and pipe it around? Edited June 17, 20241 yr by AlexanderR
June 17, 20241 yr Author On 2024/06/12 at 8:21 AM, ITS Heat Pumps - Darrel said: Morning, My advice would be Morning, my advice on this if you is if you have the budget install solar geyser as your primary source of heating and have the heat pump as your auxiliary back up. In the warmer months of the year your solar will 90 % of the work and in winter when the sun is weaker the heat pump will pick up the slack. Thanks. This does sound great. 1) Can you recommend any decent solar geysers? 2) Can it be done in phases? I.e. let's say in Winter it doesn't get warm enough, then you can add in the heatpumps? 3) If the bathrooms are on 3 different sides of the house, how would you do solar geysers? - would you have 3 solar geysers or would you have 2 and pipe it around?
June 17, 20241 yr I think you said it is not permanent home, so presume weekends/holidays. You prob expect to be popular so at times many people. Solar PV works well with permanent use but not occasional use because of high capex relative to days used per year) so I would go: 1. Big Solar thermal and a small pump off battery that circulates water from collector to large reservoir/tank whenever temp differential is enough. This should keep te reservoir well above the disease temperatures while you are away, which can happen if not warm enough. 2. A gas inline system that kicks in automatically if exit water from tank when somebody opens a tap is less than for example 45 degrees. You will likely anyway have other gas appliances. With gas you cannot run out of hot water even with 25 guests. my perm home has solar thermal + heat pump which is fine warm times of year but takes AGES in cold times. If I could re-do it I would do as I described above. Edited June 17, 20241 yr by macafrican
June 17, 20241 yr 16 minutes ago, macafrican said: I think you said it is not permanent home, so presume weekends/holidays. You prob expect to be popular so at times many people. Solar PV works well with permanent use but not occasional use because of high capex relative to days used per year) so I would go: It was indicated that they stay there permanently on page 1.
June 17, 20241 yr Author 16 minutes ago, macafrican said: I think you said it is not permanent home, so presume weekends/holidays. You prob expect to be popular so at times many people. Solar PV works well with permanent use but not occasional use because of high capex relative to days used per year) so I would go: 1. Big Solar thermal and a small pump off battery that circulates water from collector to large reservoir/tank whenever temp differential is enough. This should keep te reservoir well above the disease temperatures while you are away, which can happen if not warm enough. 2. A gas inline system that kicks in automatically if exit water from tank when somebody opens a tap is less than for example 45 degrees. You will likely anyway have other gas appliances. With gas you cannot run out of hot water even with 25 guests. my perm home has solar thermal + heat pump which is fine warm times of year but takes AGES in cold times. If I could re-do it I would do as I described above. Hi It's a permanent home! It's a fixed 5 person house. I do like your idea about solar thermal and gas! There is already gas for the hob so it shouldn't be hard to add some extra piping to a gas geyser. A Few Quick Questions If the solar geyser is on the roof, where is the gas geyser? Does it impact the pressure? Or where would the gas geyser go to keep the pressure? Any recommendations for a solar thermal geyser? We could also only do the gas system for the 1 side where there are 2 bathrooms nearby.
June 17, 20241 yr Author Here is a layout of the proposed plans! 1. Bathrooms are denoted with blue numbers. 2. Red blocks are concrete roof areas (rest is thatch) 3. Yellow arrow denoted North (for sun direction)
June 22, 20241 yr On 2024/06/17 at 4:24 PM, AlexanderR said: Hi It's a permanent home! It's a fixed 5 person house. I do like your idea about solar thermal and gas! There is already gas for the hob so it shouldn't be hard to add some extra piping to a gas geyser. A Few Quick Questions If the solar geyser is on the roof, where is the gas geyser? Does it impact the pressure? Or where would the gas geyser go to keep the pressure? Any recommendations for a solar thermal geyser? We could also only do the gas system for the 1 side where there are 2 bathrooms nearby. It isn’t a gas geyser as such - the gas system watches the water on its way out solar geyser, which runs through system like a radiator inside gas system. If temp needs it, it fires up gas and the water is heated on its way through. Pressure should be fine, but at family holiday home my experience of gas is that you should avoid mixer type taps, those ones with an arm that swings for temp and volume. I would rather have two taps and water mixes post tap on its way to shower head. Our non automatic is a Bosch one, probably stick to quality brands… The gas systems come in different sizes, down to small undercounter ones for example at an island counter basin. The gas itself must just be securely piped through house and you will need electricity there too.
June 22, 20241 yr Edit : missed that roof is thatch Edited June 23, 20241 yr by macafrican Missed answer in earlier post
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