Heat Pump Temp Setting

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E3xtc

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#171327 14-Apr-2015 07:16

Okay this is probably a really trivial question; but with the remotes for heat pumps (just standard inverter style ones; nothing weird/complex), when you adjust the temperature, does this actually adjust the temperature of the air that the unit will pump out, or does it just change the setting for the thermostat (ie the unit's goal at what it should be trying to get to - if you like)?
Am thinking/hoping that it does actually change the temperature; but when turning ours on at 3 this morning to warm my sons room I had this question ticking through my mind :)

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#1282618 14-Apr-2015 07:20

It's controlled by thermostat.

One thing that changes the temp of the incoming air could be the economy setting, if it has one, as the compressor operates at maximum efficiency not maximum power. Also once you're close to temperature it will run at lower power to increase efficiency. But you have no direct control over the air temp.

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#1282633 14-Apr-2015 08:30

the thermostat. and it's not placed where you sit, but in an obscure place between the heatpump and the wall/ceiling/etc

Jase2985

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#1282657 14-Apr-2015 08:44

some heatpumps have a second thermostat in the remote so you can leave it on the coffee table and it can use that to determine the tempertaure

i just normally set the temp to 18 (for heating) and 22 (for cooling) and the fan to auto and let it do its thing.

timmmay

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#1282658 14-Apr-2015 08:46

Auto fan is the most efficient fan setting. Manual fan can reduce efficiency - not sure by how much though. Also, keep it on heat or cool, not auto, to stop it cycling between them - which no heat pump should do anyway - but no harm.

jonathan18

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#1282659 14-Apr-2015 08:47

Weird - I was just talking to my wife about this very thing this morning! We stayed with relatives in the weekend - their heatpump was set to 30 degrees when I turned it on, and the fan up to its highest. I dropped it to 20 and fan to auto, and it heated the space perfectly and quickly.

I really think many people have no understanding of how to use thermostat controls - whether it be on a little blow heater, or a heat pump. My guess is many are under the mistaken belief that turning the thermostat up will increase the heat output.

I turned on our heatpump in the hall for the first time for the year this morning, and appreciated the "hi power" setting which I understand cranks the fan speed up and increases the thermostat by a couple of degrees for a period of about 10 minutes before dropping the temperature back to the setting and the fan speed back to auto - it does a good job of that initial warming of a large and long space.

E3xtc

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#1282665 14-Apr-2015 08:53

interesting - thanks all for the input. So I am one of those numpty muppets who assumed the temp had something to do with the output temp of the unit (wouldn't that be nice), in the same manner that a cars air con (climate control) works when you dial in a temp.....not just max freeze or max heat the buggery out of the space until the space increases/decreases to that temp.

Good to know :)

Jase2985

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#1282674 14-Apr-2015 09:04

a car works differently, as it mixes different qualtities of hot and cold air to give the desired inlet temperature.

im just amazed at the nimber of people that have the temp setting so high they can walk round in their undies in the winter. we use it to take the edge off the cold so its comfortable to sit round in pants and a jersery. and in the summer its enough so we are not sitting there sweating. its a lot more energy efficient that way so you are not trying to heat it to 25+ degrees and cool it to 18 degrees

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wasabi2k

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#1282678 14-Apr-2015 09:07

Jase2985: a car works differently, as it mixes different qualtities of hot and cold air to give the desired inlet temperature.

im just amazed at the nimber of people that have the temp setting so high they can walk round in their undies in the winter. we use it to take the edge off the cold so its comfortable to sit round in pants and a jersery. and in the summer its enough so we are not sitting there sweating. its a lot more energy efficient that way so you are not trying to heat it to 25+ degrees and cool it to 18 degrees

My wife and I battle as I am a wus (sp? woos?) with cold. We normally settle on 20 degrees, auto everything. As you said, takes the edge off without getting super hot and costing a fortune.

timmmay

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#1282696 14-Apr-2015 09:36

My wife and I are aiming for 22 degrees at the moment, but once we get used to the fact that it's cold and we get the winter clothes out and start wearing warmer clothes inside that might come down slightly. My wife's used to central heating, which brings the house up to mid twenties in every room. Kiwi homes should really be designed with heating and cooling in mind.

bfginger

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#1286834 18-Apr-2015 15:29

Many people always set the thermostat to the highest or lowest setting. For that reason heat pumps have a hidden hotel mode which restricts the heating thermostat to 25 degrees and the cooling to 20 degrees. Users can set the thermostat setting higher or lower on the interface but it's ignored.

oxnsox

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#1286882 18-Apr-2015 16:52

Jase2985: (edit)
i just normally set the temp to 18 (for heating) and 22 (for cooling) and the fan to auto and let it do its thing.

At night (winter) we turn ours down to 16, which is the minimum, means there's no real chill in the morning for the short time before you're off to work. And it doesn't run much during the day if there's a bit of sun, with no chill when you get home and tweak it back to 18-20 (depending on who operates the control).
Fan on (manual) flat out, on a really cold day, just seems to speed up the time it takes to ice up the condenser..... then there's no heat! !

nickb800

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#1286915 18-Apr-2015 18:26

jonathan18: Weird - I was just talking to my wife about this very thing this morning! We stayed with relatives in the weekend - their heatpump was set to 30 degrees when I turned it on, and the fan up to its highest. I dropped it to 20 and fan to auto, and it heated the space perfectly and quickly.

I really think many people have no understanding of how to use thermostat controls - whether it be on a little blow heater, or a heat pump. My guess is many are under the mistaken belief that turning the thermostat up will increase the heat output.

I turned on our heatpump in the hall for the first time for the year this morning, and appreciated the "hi power" setting which I understand cranks the fan speed up and increases the thermostat by a couple of degrees for a period of about 10 minutes before dropping the temperature back to the setting and the fan speed back to auto - it does a good job of that initial warming of a large and long space.

Agree that no-one knows how a thermostat works (i had a friend who thought it was a timer that turns in on for x minutes, then off for x minutes and repeats)

Part of that is due to thermostat being located somewhere irrelevant to the user - e.g. on a high-wall heat pump unit or inside the metal panel of the heater. If the thermostat location is at the right temp, then the user's location is probably a few deg below, particularly when it's warming up before the room reaches equilibrium. Cranking up the thermostat to get things started does have its place

MileHighKiwi

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#1286916 18-Apr-2015 18:27

Interesting thread. We usually set ours between 19-21 degrees and use the 'silent' mode which is essentially the fan power on 1/5.

I recall the installer saying not to use the auto option because it uses more power. After reading this thread I hsve just set the fan power to auto, to see what difference it makes than just keeping it on 1/5.

Niel

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#1286921 18-Apr-2015 18:34

It should use both the inlet air temperature and the remote control temperature. Usually it defaults to the remote control temperature, but if it can't "see" the remote then it defaults to the inlet temperature.

Agree with Timmay, don't use auto cycle. Set it to heating or set it to cooling. With auto the hysteresis is double that of manual. Not sure what it is, think it is 2 degC for manual and 4 degC for auto on my Mitsubishi. This is because on auto it has to reverse the cycle and can't do it too frequently. You also have the issue of "aircon smell" when it changes from cooling to heating, when water evaporates off the element.

Our aircon runs 24/7. We do 18 degC heating during Winter nights, 20 degC heating during Winter days, 23 degC cooling during Summer nights, and somewhere between 23 and 25 degC cooling during Summer days (changes for humidity, and 25 while we are out). Fan is set to minimum to reduce draft, louvres adjusted up in summer (cool air falls) and down in Winter (hot air rises). In Winter we also run an automatic dehumidifier. We're in Auckland, in a well insulated/sealed house.

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blakamin

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#1286928 18-Apr-2015 18:45

Ours is set on 22-23 in winter. It keeps the house perfect.

In summer we have it on 27. Any less than that and you have to start putting on winter clothes, even when it's 45 outside.

It's only on 24hrs if it's summer and a weekend, but will set the timer to turn off at 4am on work days when it's hot.
It doesn't get get cold enough in winter here to turn it on in the mornings as we're out the door in 45 minutes anyway.
On a winter weekend it might go on about mid day.

It's Panasonic E28 (8kw cooling, 9 heating).
We always keep the fan on auto, but set heating or cooling.
It uses 1/4 the electricity than our old Kelvinator that was in the house when we bought it.

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