LA3222 Posted April 25, 2022 Author Share Posted April 25, 2022 55 minutes ago, joth said: Fascinating. Do you have freeze-stat disabled? What is the outdoor temperature when it's drawing it? I will put a dedicated CT on mine just to confirm... Freeze stat is disabled. It pulls 200w as standard 24/7 which the rep at Mitsubishi didn't seem to think of as an issue, even when I pointed out that at £0.3/kwH I'm looking at throwing a good £400 away after discounting hours where it is actually used. Apparently keeping the oil warm is all part of the 'protect the compressor' ethos. I assume that it easier for them to configure the system so it does that 24/7 rather than design something which turns itself on/off with the weather conditions and the scheduled use set by the homeowner. Strange that this hasn't been discussed on here before but it seems that more and more threads are being identified where this problem is discussed - appears to be a widespread yet little know and poorly understood issue. Link to comment Share on other sites More sharing options...
SteamyTea Posted April 25, 2022 Share Posted April 25, 2022 2 minutes ago, LA3222 said: Strange that this hasn't been discussed on here before but it seems that more and more threads are being identified where this problem is discussed - appears to be a widespread yet little know and poorly understood issue. Going to be discussed more now that 2 minutes ago, LA3222 said: £0.3/kwH Except it is kWh FFS. Link to comment Share on other sites More sharing options...
LA3222 Posted April 25, 2022 Author Share Posted April 25, 2022 8 minutes ago, SteamyTea said: Going to be discussed more now that Except it is kWh FFS. Ha. The SI unit police has got me - I try to be careful because I know you are on the prowl waiting to slap a ticket on offenders, this one slipped through👀 Link to comment Share on other sites More sharing options...
joth Posted April 25, 2022 Share Posted April 25, 2022 14 minutes ago, LA3222 said: It pulls 200w as standard 24/7 That's 200W. And I guess 24/7 is unitless 😂 Link to comment Share on other sites More sharing options...
LA3222 Posted April 25, 2022 Author Share Posted April 25, 2022 1 minute ago, joth said: That's 200W. And I guess 24/7 is unitless 😂 Damn. Two in one day....I'm off to go work on the bathroom😅 Link to comment Share on other sites More sharing options...
SteamyTea Posted April 25, 2022 Share Posted April 25, 2022 (edited) 15 minutes ago, joth said: 24/7 is unitless Back in 1999 I was stopped in the street and asked if I knew what 24/7 meant. I had know idea, but my partner did. They did the shopping. How about 24/7/52 Or is that a birthday. Small list: https://famouspeople.astro-seek.com/famous-birthdate/24-july-1952 Edited April 25, 2022 by SteamyTea Link to comment Share on other sites More sharing options...
SteamyTea Posted April 25, 2022 Share Posted April 25, 2022 23 minutes ago, LA3222 said: SI unit police It is a derived unit, from the SI units for kilograms, metres and seconds. Link to comment Share on other sites More sharing options...
JamesPa Posted April 25, 2022 Share Posted April 25, 2022 Do we know whether the consumption occurs only in standby or whether it's a continuous load even when the compressor is working. If it's the former then potentially it's not so serious provided the system is heating or turned fully off most of the time. I'm not trying to excuse the waste, just trying to understand how big it actually is. Link to comment Share on other sites More sharing options...
ProDave Posted April 25, 2022 Share Posted April 25, 2022 20 minutes ago, JamesPa said: If it's the former then potentially it's not so serious provided the system is heating or turned fully off most of the time. Yes but to turn it fully off means turning the power off, and there was mention of 2 hours warm up time required? So not an easy "solution" Until told otherwise, look for an ASHP with a scroll compressor which don't seem to need this heater? Link to comment Share on other sites More sharing options...
Radian Posted April 25, 2022 Share Posted April 25, 2022 Is this 200W real? I mean like a resistive load with a power factor of one? A crankcase heater would be but a compressor might not. My fridge and freezers have a PF of around 0.5 so they show up on simple current clamp meters as drawing twice as much power as they are billed for. Link to comment Share on other sites More sharing options...
markocosic Posted April 25, 2022 Share Posted April 25, 2022 You're correct in thinking that this doesn't show up on the official sCOP figures. If true the your standby loss / their warranty saving. Mitsubishi also advise really terrible heating circuit designs (mixing headers) to avoid callbacks due to insufficient flowrate on the space heating circuit. Again your COP loss / their tech support saving. Air conditioning manufacturer with a bodhe product and an amoral UK sales outfit? Link to comment Share on other sites More sharing options...
SteamyTea Posted April 25, 2022 Share Posted April 25, 2022 26 minutes ago, Radian said: Is this 200W real Hopefully we will find out with a bit more investigation. How low could a compressor motor go in the power factor. 0.5 is appealing. Link to comment Share on other sites More sharing options...
dpmiller Posted April 25, 2022 Share Posted April 25, 2022 11 minutes ago, SteamyTea said: 39 minutes ago, Radian said: Hopefully we will find out with a bit more investigation. How low could a compressor motor go in the power factor. 0.5 is appealing. but it's not being "motored", it's a resistive heater at that point... Link to comment Share on other sites More sharing options...
SteamyTea Posted April 25, 2022 Share Posted April 25, 2022 3 minutes ago, dpmiller said: but it's not being "motored", it's a resistive heater at that point... Not totally sure, it may act as an inductor, with thermal energy being a by product. @Radian would know more. Link to comment Share on other sites More sharing options...
Radian Posted April 25, 2022 Share Posted April 25, 2022 (edited) 18 minutes ago, SteamyTea said: Not totally sure, it may act as an inductor, with thermal energy being a by product. @Radian would know more. Very much doubt that, not at 50Hz anyway. But there was some talk of the motor windings being used to double-up as heaters? So maybe some higher-frequency PWM applied to the compressor motor which would almost certainly have a lower PF. The utility companies meter would only register real power so if that was used to establish the vampire load that would clinch it. Alternatively many of the smart sockets with power monitoring can be made to expose VA and VAR if they are reflashed with Tasmota. That's how I got the insights into my fridge freezer power use (all three plugged into same smart socket): Edited April 25, 2022 by Radian Link to comment Share on other sites More sharing options...
joth Posted April 25, 2022 Share Posted April 25, 2022 Just now, Radian said: Alternatively many of the smart sockets with power monitoring can be made to expose VA and VAR if they are reflashed with Tasmota All the best plugging a 32A heat pump into a tuya wall socket 😅 Link to comment Share on other sites More sharing options...
Kenway Posted April 25, 2022 Share Posted April 25, 2022 My Eco Dan uses 300w constant until I turned it off at the wall! 😁👍 Link to comment Share on other sites More sharing options...
Kenway Posted April 25, 2022 Share Posted April 25, 2022 I probably only need it on in BST 3 hours a day to top up the Hot Water. I’m going to create a workaround with a 4 ch relay that schedules the heat pump to come on 4 hours during mid day and 1 hour of that use the external boiler function to block the HW and Heating inputs that way its warming the oil before kicking in. shame I have to create a work around think this function would be built into the FTC Eco mode but I found that the Eco mode doesn’t do anything or make any changes to how the system functions . Link to comment Share on other sites More sharing options...
ReedRichards Posted April 25, 2022 Share Posted April 25, 2022 5 hours ago, JamesPa said: ...And another here https://forums.moneysavingexpert.com/discussion/6298830/dimplex-ashp-running-cost with figures for Daikin, LG and Dimplex all of which seem to have quite high standby consumption if this post is to be believed. Not exactly. Dimplex and Daikin ASHPs are stated to have a vampire load. LG's are stated not to have perceptible vampire load (BY ME!). I happen to know that the Daikin ASHP referred to is about 10 years old so what is stated might not be true for contemporary units. Link to comment Share on other sites More sharing options...
JamesPa Posted April 26, 2022 Share Posted April 26, 2022 7 hours ago, ReedRichards said: Not exactly. Dimplex and Daikin ASHPs are stated to have a vampire load. LG's are stated not to have perceptible vampire load (BY ME!). I happen to know that the Daikin ASHP referred to is about 10 years old so what is stated might not be true for contemporary units. Apologies for my skim reading! Link to comment Share on other sites More sharing options...
joth Posted April 26, 2022 Share Posted April 26, 2022 (edited) 8 hours ago, Kenway said: My Eco Dan uses 300w constant until I turned it off at the wall! 😁👍 I don't understand this graph, as it's plotting kWh against time. Is that kWh per hour? Also known as kW (averaged over an hour). If so, yes that does seem to be 300 W 😮 I've just put a dedicated CT clamp on my ecodan and it's happily drawing 3.7W. And it's been below 5ºC overnight. Something fishy going on here. I'll leave mine logging add day, and force heat some extra DHW later once PV is going, and see how the power profile looks. Edited April 26, 2022 by joth Link to comment Share on other sites More sharing options...
SteamyTea Posted April 26, 2022 Share Posted April 26, 2022 9 hours ago, Radian said: Very much doubt that, not at 50Hz anyway May be a DC voltage as it is an inverter unit. Link to comment Share on other sites More sharing options...
MikeSharp01 Posted April 26, 2022 Share Posted April 26, 2022 Just did a back of fag packet thought experiment calculation on the real COP on a 5Kw (COP 3) unit (worst case) with 300W vampire load load and assuming 6 months of heat and DHW and 6 months just DHW comes out at 2.02! Link to comment Share on other sites More sharing options...
dpmiller Posted April 26, 2022 Share Posted April 26, 2022 ^yep DC injection would do it. I've just re-read the TUV report for the CE-iVT9, and it quotes standby at 9W and the crankcase heater at an additional 33W Link to comment Share on other sites More sharing options...
SteamyTea Posted April 26, 2022 Share Posted April 26, 2022 4 minutes ago, MikeSharp01 said: 5Kw Fluttering your eyelids won't get you extra marks, did not help Angela Rainer. Did you make any assumption on the time to heat i.e. DHW heating for 5 hours, CH on for 14 hours. Link to comment Share on other sites More sharing options...
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