Heat Pumps: anyone have one/thought about it?

It loses about 1C every two hours, so the hot water cycle finishes at 1am and its at 48C then but will have dropped to 40C by 5pm. This is without any defrosts.

A passing three way valve was my guess too, but it could be normal going by what shroomz says above if theirs is similar?
 
1C every 2 hours is normal. It would be abnormal if it was dropping 8C in a few hours.

The heat loss slows as the difference between the tank and the air temperature gets closer.

The slimline tank has a higher heat loss because it’s got more surface area for the same volume of water. There is not much more to it than that really.

You can put extra jackets on them (I have on my buffer tank as it’s in the loft).

You can add insulation to all the fittings around the cylinder. They are right up against the cylinder and heat will pass along the pipework. Expectations on how much you save should be managed, it’s a tiny amount of the lost heat in reality.
 
It hasn't been an issue, it just seemed fast to me, but its the first time Ive had a water cylinder (always combis before this), so had no idea. We're still on an electric shower for now, so its only really used for baths and general stuff and has never ran out on us yet.
 
b0rn2sk8 said:
1C every 2 hours is normal. It would be abnormal if it was dropping 8C in a few hours.

The heat loss slows as the difference between the tank and the air temperature gets closer.

The slimline tank has a higher heat loss because it’s got more surface area for the same volume of water. There is not much more to it than that really.

You can put extra jackets on them (I have on my buffer tank as it’s in the loft).

You can add insulation to all the fittings around the cylinder. They are right up against the cylinder and heat will pass along the pipework. Expectations on how much you save should be managed, it’s a tiny amount of the lost heat in reality.
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I also did the Volumiser which is off to the left. Over serval mild 10C days mine appears to lose 0.42C every hour so not bad for a loft location.

flC3UNa.jpg
 
If I was a rapper, I'd make a song about jackets for dogs and jackets for water cylinders :)

My heat pump install finished today. From what I can see, the Octopus guys did a good job. Except one issue - the electrician run the cables from the heat pump to the water cylinder/control panel through the loft. He took some boards up and a big log, which is part of the structural support - put in the cables and didn't bother to put the boards and the log back - just left the laying around...

dymLe82P346D.jpg
 
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If I was a rapper I'd make a song about last week I had a roof now it has all blown away.

That 'log' looks surprisingly like a purlin beam used to support the sloping rafters and tie all to the gable ends. I may be wrong.
 
Is there a way to see a log of schedules that have run in the past with Daikin?

I set a schedule for the water cylinder heating to run in Eco mode from 3am to 4:30am - and that seems to have run fine, as the hot water was at 45C in the morning. But the house heating schedule - 21C from 11:30pm to 5:30pm (i'm on iGo) - looks like it didn't run at all. The temperature in the morning was 14C.
 
Its really getting tested tonight! Its 1C outside with a 25-30mph wind blowing right at the front of the house. Im having to run a +5C leaving water temp offset this evening as it doesn't take into account the windchill when running pure weather compensation. I imagine heat loss is massively higher in these conditions.

Its currently running at 44C LWT instead of 39C. Power usage is about 1.38kW at this temp. The air is quite dry so there havent been any defrost cycles yet meaning COP is still around 3.5-4.0 though.
 
SkyTerran said:
Is there a way to see a log of schedules that have run in the past with Daikin?

I set a schedule for the water cylinder heating to run in Eco mode from 3am to 4:30am - and that seems to have run fine, as the hot water was at 45C in the morning. But the house heating schedule - 21C from 11:30pm to 5:30pm (i'm on iGo) - looks like it didn't run at all. The temperature in the morning was 14C.
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I'll assume you meant 11-30pm to 05:30am.

As mentioned there is a bug with simultaneous starts. I found that so long as the heating schedule starts before the DWH schedule. The water heating will take priority without issue and the house heating will resume once the diverter valve has rotated back. However yours does not appear to have done that.

The fact the schedule visibly initiated in the app for example will not help as my DHW schedule would indicate the 46C heating target. The valve would rotate to the DWH cylinder circuit. The water pump would ramp up but the compressor would not start.

First thing to do would be to would be to initiate a resync of the modules by making any small change in the MMI i.e. reboot. Maybe even a power cycle of the system.
 
Yeah, sorry I meant 05:30am.

If I have the home heating on for a 6 hour interval during the night, and the water cylinder heating for say 1.5 hours inside that - would it resume heating house right after the cylinder reaches the target temperature, or will it wait for the full period in the cylinder schedule to finish?

This Daikin app is quite limited. I don't see an indication of what the pump is currently doing - is it off, is it heating the house or the water cylinder.

Also currently no one lives in this house. I set the water cylinder to re-heat when it reaches 30C. But if I decide to go there I may want to heat the water to say 45C through the Daikin app - and I don't see a way to do it.
 
SkyTerran said:
Yeah, sorry I meant 05:30am.

If I have the home heating on for a 6 hour interval during the night, and the water cylinder heating for say 1.5 hours inside that - would it resume heating house right after the cylinder reaches the target temperature, or will it wait for the full period in the cylinder schedule to finish?

This Daikin app is quite limited. I don't see an indication of what the pump is currently doing - is it off, is it heating the house or the water cylinder.

Also currently no one lives in this house. I set the water cylinder to re-heat when it reaches 30C. But if I decide to go there I may want to heat the water to say 45C through the Daikin app - and I don't see a way to do it.
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Yes I have my heating set to 19C between 13:00 - 16:00. The house will usually be between 17.5C - 18C by then so the heat pump turns on. During this period between 14:00 - 16:00 I set the DWH temp to 46C (Comfort). The heat pump prioritises water heating for ~30 mins and then switches back to heating the house. At 16:00 the room set point temp changes back to 18C and the heat pump switches off.

The other way I know the heat pump is working as intended is to open the Octopus Energy app and check the live power reading. When the heating cycle starts from cold the power draw will go up to 1.3-1.6KW (4KW Daikin) and then ramp down to 300-500W. The water heating cycle ramps from 1KW to 3.5KW until the DWH target is reached at which point it may go back to heating.

Agreed why is such a simple indication not obvious in the app. At least on the room thermostat the blue LED ring is glowing.

You can use the Powerful mode to use the immersion element to heat the water on demand.
 
SkyTerran said:
Yeah, sorry I meant 05:30am.

If I have the home heating on for a 6 hour interval during the night, and the water cylinder heating for say 1.5 hours inside that - would it resume heating house right after the cylinder reaches the target temperature, or will it wait for the full period in the cylinder schedule to finish?

This Daikin app is quite limited. I don't see an indication of what the pump is currently doing - is it off, is it heating the house or the water cylinder.

Also currently no one lives in this house. I set the water cylinder to re-heat when it reaches 30C. But if I decide to go there I may want to heat the water to say 45C through the Daikin app - and I don't see a way to do it.
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Yes, the app is totally useless. It doesn't show any information at all.

If you have a 6 hour schedule overnight, it will run in heating mode until the DHW schedule time and then switch to that. Once the water is up to temp, it will immediately switch back to heating mode. It will do this regardless of the time taken to heat the water, so if you allocate a 90 minute slot for DHW but it only takes 50 minutes to get up to temp, then it will switch back to heating after the 50 minutes.
 
You stop caring very quickly what it’s doing as long as your house is warm, your hot water is hot and it’s not using an absorbent amount of electricity.
 
Don't think that's a good excuse for missing basic functionality. At the very least it makes it very hard to troubleshot any issues through the app.

I've sent an email to [email protected] with the issues I see in the app. If a few more Daikin users from the forum do the same, there's a small chance the app can get some improvements.
 
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There is zero chance of that happening.

Once it’s all set up and dialled in, you’ll seldom look at it. That said the app is by far the easiest way to set up schedules but everything else is done via the controller.

The grass isn’t greener elsewhere, most manufacturers are the same.
 
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