The usual ignorance in the comments on that article. I can never understand why some are so hostile to solar/EVs/heat pumps? It's bizarre.
Heat Pumps: anyone have one/thought about it?
- Thread starter fish
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They probably get their info from Facebook, or they've had a bad install, or they try to use them like a boiler.
We know better though, a little over four weeks until my installation.
Yes I agree it is down to the design of the system. Octopus was very good we had two site visits our heat loss was calculated at 7.6kW, first visit suggested a 8kW system first but this was upgraded to a 9kW heat pump after the second visit in the end. Maybe we could have run with the 8kW which would be cheaper to run but the house is very large.
We did have a number of problems in balancing the underfloor heating down stairs to upstairs that has radiators to the bedrooms. Took them a few visit to resolve the issues, I did ask them to upsize the radiators more so we could run at a lower flow temperature to improve the efficiency of the heap pump. I only had the system installed for the last 6 months, but when I checked the SCOP was just over 3.6 not to bad.
Octopus originally set up the heat pump as a single zone but were forced to reinstall the underfloor heating actuators with the individual room thermostatics downstairs as we found that some rooms were getting to hot.
We found that the heat pump does keep the house warm, works very well with underfloor downstairs but upstairs bedrooms are cooler but not cold, still a learn curve for us.
I would say that it is important to get the radiators sized correctly in the design and the size of the heap pump some companies suggested 11kW to us .
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My heat pump naturally cycled off today for the first time since winter due to the heat loss dropping below it’s minimum output.
Outside of my usual overnight preheat on off peak electricity, it’s only ran for about 3 hours today.
We are currently at 22.3 on the thermostat so it’s going to be awhile before it comes on again tonight, if at all. My office is a nice and toasty 23.3C.
It will be short lived mind, it’s due to drop off again next week. As I said in the solar thread, this week has been a bit of a blip in the matrix.
Outside of my usual overnight preheat on off peak electricity, it’s only ran for about 3 hours today.
We are currently at 22.3 on the thermostat so it’s going to be awhile before it comes on again tonight, if at all. My office is a nice and toasty 23.3C.
It will be short lived mind, it’s due to drop off again next week. As I said in the solar thread, this week has been a bit of a blip in the matrix.
I suspect we're going to have issues like this that have to be ironed out when ours goes in. Although overall the house is still cold enough to need heat at the moment, the kitchen is a wall of windows and heats up to 25C now when it's sunny. We usually just turn off the radiators in there at this time of the year, but I understand this isn't a good idea on a heat pump system. Octopus have actually suggested two radiator upgrades in there for the heat loss too.
As your room temperature goes up, the output of your radiators drops due to the temperature difference being reduced.
You’ll probably find it’s fine but you can use your TRVs as needed to prevent overheating (say set them to 4 of 5).
If you are getting a Daikin heat pump, it has a setting called ‘modulation’ which can use the Daikin thermostat to adjust the weather compensation curve based on how far you are overshooting or undershooting the temperature target.
You’ll probably find it’s fine but you can use your TRVs as needed to prevent overheating (say set them to 4 of 5).
If you are getting a Daikin heat pump, it has a setting called ‘modulation’ which can use the Daikin thermostat to adjust the weather compensation curve based on how far you are overshooting or undershooting the temperature target.
Has the temperature and quantity of DHW been OK then, for washing up during food prep/shaving ... ? where often use temperatures higher than showers (any immersion heater boosting needed)
Yes I found the hot water to be fine, Heat pump is set to heats up the 300L water cylinder to 52degC overnight using cheap electricity for 1.30 hours. I then use the Eddi to boost with the immersion heater to 60degC for 30 minutes at 4am. The Eddi will use any surplus power from the solar to reheat the water cylinder again if required.
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The TRV to the upstairs radiators are fully open the heat pump was setup with the Daikin thermostatic in the main bedroom with weather compensation curve.
We found that we needed to use the individual room thermostatics downstairs to prevent overheating in some of the smaller rooms as the builder had set the house up with 12 separate heating loops on the manifold.
Octopus originally had the Daikin thermostatic downstairs in the hall but was switching off too soon so very little heating upstairs, this was later moved upstairs to allow the radiators to stay on longer which worked for us.
Yes it is a Daikin heat pump so I going to have a play with the ‘modulation’ setting
thanks- so that's 3/4 Kwh you take from your battery to boost water temp, to leave some headroom in the batteries for following days solar - without solar just using cheap electricity wouldn't be too dear either.
My combi's set at circa 60C and with pipework losses mostly use unmixed hot water in the kitchen, or bathroom basin
(e: thinking about it the cost of topping up the hot water temp 52->60 at overnight rate has similar cost to using gas ...
just checking - hadn't appreciated you can get gas powered heat pumps lol ]
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Hot water heating is done overnight at the same time as the 40 kWh batteries are being charged using the off peak electricity (7p per kWh) as I am on the tariff Intelligent Go with Octopus.
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To manage expectations, you won't get an ASHP quickly.
By the time an installer has been booked, attended to do the survey, designed the installation, agreed the price, booked the installation, done the paperwork to get the grant and finally installed, you are looking at a timeline measured in months, not days.
By the time an installer has been booked, attended to do the survey, designed the installation, agreed the price, booked the installation, done the paperwork to get the grant and finally installed, you are looking at a timeline measured in months, not days.
My gas boiler only lasted 10 years before the heat exchanger started to leak.
I was lucky that it failed in April last year and I was able to run the hot water from the Eddi but ASHP process took 6 months for me not a quick job.
My ASHP was done by Octopus much cheaper than other companies quoted me.
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I was expecting some issues with balancing the underfloor heating down stairs to upstairs that has radiators. I general I have been happy with Octopus process in resolving these issues that we had.
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Soldato
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Is this for pasteurisation?