Thanks Graeme, ive been installing heat pumps for nearly 10 years now and only have got round to installing one in my own house in the last week. If you need any more info let us know.
Hi Ken great video. You mentioned at the end that it’s clinically proven humans like slower changes in temperature, sounds interesting and just wondered if you had a reference for that, as I struggled to google one… Thanks
Great vid. I had a Daikin heat pump retro fitted last summer but my bills thru these winter months are sky high, it struggles to hit my target temp of 20degrees. I checked the controller and noticed the LWT was fixed at 30 degrees so I've upped it to 35 to get more heat. The installers never set weather dependant heating which I think was a bit crappy. In the settings I can change from fixed to WD but can't find anywhere in the menu to set the curve. I would be greatful for any advice. Unit is a Daikin Altherma
Sounds like it's still on factory default. Could be a few things, get your installer back. If you have radiators then it should be running like 45-50⁰ when minus 2⁰ or something. I spend around 4-7 pounds a day in my own home, which is not perfectly insulated, In the real nasty weather. But in the summer, I'm down to like .50p per day, but that's because I have the PV and battery.
It would be good if there was a list that indicated which heat pumps might hit the best sweet spot in different areas(im in central scotland, but high elevation, colder temps due to wind chill etc.)
Things have moved on so much since I did this video. Using a R290 refrigeration unit with a large evaporator coil is the best for prolonged colder situations. The R290 Refrigeration window is very good, both at low and high ambient conditions. Get a slightly bigger heat pump, have your heating design for lower than the average Ie -4⁰ if your normal average was -2⁰. Heat pumps can work down to -25⁰, BUT if your system has only been designed to -2⁰, then having ambient conditions of -4/6⁰ you will be cold.
I set up weather comp 25flow/15ambient and 45flow/-12 ambient. It’s been tested down to -3.5 ambient and it maintained the room setpoint nicely. Double sized radiators compared to my gas boiler. CoP is right on the published figures from 0 ambient to 7 ambient. Hitting around 4.5. Above that ambient temperature, the CoP falls off. It falls down to about 3.2 at 12 ambient. The minimum consumption from the Heatpump is a problem. It can get as low as 0.5 Amps, and in that regime I get excellent CoP of around 6. But other times the consumption minimum is 1.3 Amps, and the CoP will crash. Very weird and no rhyme or reason for it.
thanks for the video! I'm wondering if it is possible to integrate ASHP with heat storage (e.g. water tanks) to shift the load to off-peak hours? does it mean HP needs to produce a higher temperature (lower COP) to compensate for the loss in storage, and/or need two tanks to store at two temperatures (high/low)? many thanks!
Yes, I have a system from a company called Homely Energy, it automatically runs my heat pump at the cheaper hours, to either load my hot water or my heating buffer tank.
Barton Chen my heat pump only does 55max, so my hot water is stored around 50 and the same when I had a gas boiler. The heating works on weather curve from a15 w25 to a2 w50, I’m hoping to increase the size of the buffer to 200, just need to see how much room I have left.
@@allthingsrenewable9017 Thanks for your reply again. I thought hot water should >60 C to reduce the risk of Legionella growth... anyway, I guess heat pump is quite efficient already, so adding a larger buffer tank may not save too much...
Here's some crazy numbers relating to my Daikin Altherma EDLQ-CV3 operation: It's-2°c outside. The room temperature reading at the wall thermostat is 19°c. At the staircase level below the thermostat it's 14°c. Meanwhile, in the lounge, at head height it's 27°c whilst at the carpeted floor level it is 17.5°c. It's only 5:30am and since midnight it's used 8kWh because for some reason it's running on weather dependent mode constantly
It helps to understand why COP changes as it does. A heat pump doesn't generate heat, it simply moves it around - Better yet it takes thermal energy from the outside and converts it to usable thermal energy on the inside. (I.e. At a higher temperature) There's no free lunch, so if you ask the heat pump to do more work (Increase the temperature by a greater amount, either because the outside temperature is lower or the inside temperature you're asking for is higher, then it has to work harder. It's as simple as that - Ask it to work harder and you'll get less for the electrical energy you put in.
It’s pretty simple Coefficient of Power is a relationship between straight electric heat which is a COP of 1:1 and a heat pump. Simply put, with electric heat you buy a watt of power from the utility and a watt of heat(less losses) come out the register vent. With a heat pump you buy a watt of power from the utility and 2 or 3 watts come out the vent. As it gets cooler outside the advantage decreases.
Im Sparky UK tradesmens ..man&boy, now live in Australia & and got my refrigerant licence . Heatpumps h2o my game now. Trying to explain to people why there Heatpump don't work is a mission in its self...Pool heating..heater capacity is undersized..15kw hp heating 50k lts pool to 28° Lol .. why the hell would u rip gas boilers to install heatpumps for hot water, ive no idea.. cop for the heatpump for heating h2o @ 0° which when u want it..(in u.k.) which im sure gas would be cheaper.. on comparison..? Like to see engineers evaluation in $ KEN . with the UK government push to sell heatpumps ? Horses for Courses! Let's face it Ken Gov never right. Corps tell gov what to push. That's fact
Fantastic explenation !
Hello young Ken thank you for the video I learned something
Thanks Ken. It will be interesting to see the take up of Ashp over the coming years. Bring it on..
Thanks Graeme, ive been installing heat pumps for nearly 10 years now and only have got round to installing one in my own house in the last week. If you need any more info let us know.
Excellent Ken
Hi Ken great video. You mentioned at the end that it’s clinically proven humans like slower changes in temperature, sounds interesting and just wondered if you had a reference for that, as I struggled to google one… Thanks
Look up how temperature changes effect the body.
Great vid. I had a Daikin heat pump retro fitted last summer but my bills thru these winter months are sky high, it struggles to hit my target temp of 20degrees. I checked the controller and noticed the LWT was fixed at 30 degrees so I've upped it to 35 to get more heat. The installers never set weather dependant heating which I think was a bit crappy.
In the settings I can change from fixed to WD but can't find anywhere in the menu to set the curve. I would be greatful for any advice. Unit is a Daikin Altherma
Sounds like it's still on factory default. Could be a few things, get your installer back. If you have radiators then it should be running like 45-50⁰ when minus 2⁰ or something. I spend around 4-7 pounds a day in my own home, which is not perfectly insulated, In the real nasty weather. But in the summer, I'm down to like .50p per day, but that's because I have the PV and battery.
best explanation of this i have seen ken. Mustard mate
Good on you mate keep them coming 👍👌
Cheers Stu, plenty to talk about coming up, lets do an interview sometime.
It would be good if there was a list that indicated which heat pumps might hit the best sweet spot in different areas(im in central scotland, but high elevation, colder temps due to wind chill etc.)
Things have moved on so much since I did this video. Using a R290 refrigeration unit with a large evaporator coil is the best for prolonged colder situations.
The R290 Refrigeration window is very good, both at low and high ambient conditions.
Get a slightly bigger heat pump, have your heating design for lower than the average Ie -4⁰ if your normal average was -2⁰.
Heat pumps can work down to -25⁰, BUT if your system has only been designed to -2⁰, then having ambient conditions of -4/6⁰ you will be cold.
Great explanation thank you
I set up weather comp 25flow/15ambient and 45flow/-12 ambient. It’s been tested down to -3.5 ambient and it maintained the room setpoint nicely. Double sized radiators compared to my gas boiler.
CoP is right on the published figures from 0 ambient to 7 ambient. Hitting around 4.5. Above that ambient temperature, the CoP falls off. It falls down to about 3.2 at 12 ambient. The minimum consumption from the Heatpump is a problem. It can get as low as 0.5 Amps, and in that regime I get excellent CoP of around 6. But other times the consumption minimum is 1.3 Amps, and the CoP will crash. Very weird and no rhyme or reason for it.
Well done Ken !
Thanks Rob, hope your well :-)
Very comprehensive nice explanation
How do the lines drawn relate to the cop
thanks for the video! I'm wondering if it is possible to integrate ASHP with heat storage (e.g. water tanks) to shift the load to off-peak hours? does it mean HP needs to produce a higher temperature (lower COP) to compensate for the loss in storage, and/or need two tanks to store at two temperatures (high/low)?
many thanks!
Yes, I have a system from a company called Homely Energy, it automatically runs my heat pump at the cheaper hours, to either load my hot water or my heating buffer tank.
@@allthingsrenewable9017 Thanks for your reply! I suppose the temperature for hot water (>60 C?) is higher than space heating (
Barton Chen my heat pump only does 55max, so my hot water is stored around 50 and the same when I had a gas boiler. The heating works on weather curve from a15 w25 to a2 w50, I’m hoping to increase the size of the buffer to 200, just need to see how much room I have left.
@@allthingsrenewable9017 Thanks for your reply again. I thought hot water should >60 C to reduce the risk of Legionella growth... anyway, I guess heat pump is quite efficient already, so adding a larger buffer tank may not save too much...
Barton Chen legionella cycle is done once a week, via MyEnergi Eddie.
Here's some crazy numbers relating to my Daikin Altherma EDLQ-CV3 operation:
It's-2°c outside. The room temperature reading at the wall thermostat is 19°c. At the staircase level below the thermostat it's 14°c.
Meanwhile, in the lounge, at head height it's 27°c whilst at the carpeted floor level it is 17.5°c. It's only 5:30am and since midnight it's used 8kWh because for some reason it's running on weather dependent mode constantly
I've seen so many explanations of COP by now and from 10 people I've heard 8 different opinions so I'm mad as h**l
It helps to understand why COP changes as it does. A heat pump doesn't generate heat, it simply moves it around - Better yet it takes thermal energy from the outside and converts it to usable thermal energy on the inside. (I.e. At a higher temperature)
There's no free lunch, so if you ask the heat pump to do more work (Increase the temperature by a greater amount, either because the outside temperature is lower or the inside temperature you're asking for is higher, then it has to work harder.
It's as simple as that - Ask it to work harder and you'll get less for the electrical energy you put in.
It’s pretty simple Coefficient of Power is a relationship between straight electric heat which is a COP of 1:1 and a heat pump. Simply put, with electric heat you buy a watt of power from the utility and a watt of heat(less losses) come out the register vent. With a heat pump you buy a watt of power from the utility and 2 or 3 watts come out the vent. As it gets cooler outside the advantage decreases.
Im Sparky UK tradesmens ..man&boy, now live in Australia & and got my refrigerant licence . Heatpumps h2o my game now.
Trying to explain to people why there Heatpump don't work is a mission in its self...Pool heating..heater capacity is undersized..15kw hp heating 50k lts pool to 28° Lol .. why the hell would u rip gas boilers to install heatpumps for hot water, ive no idea.. cop for the heatpump for heating h2o @ 0° which when u want it..(in u.k.) which im sure gas would be cheaper.. on comparison..? Like to see engineers evaluation in $ KEN . with the UK government push to sell heatpumps ? Horses for Courses! Let's face it Ken Gov never right. Corps tell gov what to push. That's fact
Wish our Daikin Altherma had a COP of 5! 2.7 is the average over the year.
You may want that looked at, I'm running around 4.5 cop.
Is your figure of 4.5 a calculated COP or is it the figure on the spec. label of the outdoor unit?@@allthingsrenewable9017