Advice wanted re Heat Pumps

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86 posts

Master Geek

#1949412 31-Jan-2018 15:36

After a bit of research I have become a little confused with Mitsubishi:
Their add says:
While ordinary heat pumps produce less heat below 7°C, only HyperCore® guarantees its fully rated capacity right down to -15°C

1. Mitsubishi advertise their HyperCore Heat Pump as providing full power from minus 15 deg C.

2. They say other standard pumps do not even at 7deg C.

3. My room being 136 cu meters requires a power rated pump of 8.3Kw but Mitsubishi do not make a HyperCore pump of that size their max is 6.8Kw (MFZ-KJ60VEHZ)

4. In their “G series” they do make a pump of 9Kw (MSZ-GE80VAD) which seems the way to go and has low temp performance down to minus 15deg C’
This goes against their advertised benefits of HyperCore that “other pumps struggle at temps of 7deg C and lower” so if true is not going to be of much use in the winter.

I think their advertising of the HyperCore is really saying our other pumps are not that good at cold temps, yet the “other pump” advertising says good down to minus 15degC. ?????

I think the G series would do the job.

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Batman

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#1949415 31-Jan-2018 15:44

but the other pumps will struggle at -15. yes it will work, but only some of the time.

when it works at low temps the compressor will freeze. then it stops producing heat to your room while it defrosts.

mitsubishi has heating elements on the compressor so it will never freeze. so it remains warm and can transfer heat in to your room.

some heat pumps have segmental defrost where it will defrost bits of the compressor while the other bits of the compressor goes at half blast.

madcarue

86 posts

Master Geek

#1949418 31-Jan-2018 15:48

I will never get as low as -15C we have had -3 but not often. are you saying all Mitsubishi pumps have heated compressors?

chimera

448 posts

Ultimate Geek

#1949486 31-Jan-2018 16:32

I run Fujitsu heat pump, really happy with it, works well - although as above haven't got down to that low degrees so don't know how well they function at near zero.

Also use an Ambiclimate to control on/off, comfort levels, etc automatically. Highly recommend them, awesome little boxes. http://www.ambiclimate.com/

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#1949584 31-Jan-2018 19:04

madcarue:

I will never get as low as -15C we have had -3 but not often. are you saying all Mitsubishi pumps have heated compressors?

mattwnz

19383 posts

Uber Geek

#1949587 31-Jan-2018 19:09

madcarue:

After a bit of research I have become a little confused with Mitsubishi:
Their add says:
While ordinary heat pumps produce less heat below 7°C, only HyperCore® guarantees its fully rated capacity right down to -15°C

1. Mitsubishi advertise their HyperCore Heat Pump as providing full power from minus 15 deg C.

2. They say other standard pumps do not even at 7deg C.

3. My room being 136 cu meters requires a power rated pump of 8.3Kw but Mitsubishi do not make a HyperCore pump of that size their max is 6.8Kw (MFZ-KJ60VEHZ)

4. In their “G series” they do make a pump of 9Kw (MSZ-GE80VAD) which seems the way to go and has low temp performance down to minus 15deg C’
This goes against their advertised benefits of HyperCore that “other pumps struggle at temps of 7deg C and lower” so if true is not going to be of much use in the winter.

I think their advertising of the HyperCore is really saying our other pumps are not that good at cold temps, yet the “other pump” advertising says good down to minus 15degC. ?????

I think the G series would do the job.

Are you talking about the GE series, or the GL series?

The GL series is their newer range, and I believe it is called ecoCORE. That appears to be the inbetween range between the hypercore, and the basic GE series. We are looking at the GL series, in the largest size, because they don't do a large hyperCore version.. I also noticed that they advertise they are the quietest heat pumps. However the specs on the Panasonic, shows that it has the same decibel rating. The retail store were pushing really hard for us to go for the Panasonic, and how much better they were, but they didn't sway us.

Would be interested if other people have feedback on the newer GL series, and whether it is worth the extra price difference. Apparently it uses a different refrigerant which is more eco friendly. Just a pity it doesn't yet work with their multisplit system.

Also if anyone has any opinion on the designer series models, I would be interested. I hate white plastic that goes yellow, so was looking at the silver designer series models for a multisplit system. The specs do seem slightly better than the GE series, and they are less bulky looking. Only problem is I can't find anywhere in Wellington that has the silver unit on display, they are all piano black.

Aredwood

3885 posts

Uber Geek

#1949752 31-Jan-2018 22:18

@madcarue Just check the COP Vs temp tables of any heatpump that claims to still have full output even at really low temperatures. Some models have heating elements inside the indoor units, which are used to maintain the output.

madcarue

86 posts

Master Geek

#1950118 1-Feb-2018 14:04

mattwnz:

Are you talking about the GE series, or the GL series?

The GL series is their newer range, and I believe it is called ecoCORE. That appears to be the inbetween range between the hypercore, and the basic GE series. We are looking at the GL series, in the largest size, because they don't do a large hyperCore version.. I also noticed that they advertise they are the quietest heat pumps. However the specs on the Panasonic, shows that it has the same decibel rating. The retail store were pushing really hard for us to go for the Panasonic, and how much better they were, but they didn't sway us.

Would be interested if other people have feedback on the newer GL series, and whether it is worth the extra price difference. Apparently it uses a different refrigerant which is more eco friendly. Just a pity it doesn't yet work with their multisplit system.

Also if anyone has any opinion on the designer series models, I would be interested. I hate white plastic that goes yellow, so was looking at the silver designer series models for a multisplit system. The specs do seem slightly better than the GE series, and they are less bulky looking. Only problem is I can't find anywhere in Wellington that has the silver unit on display, they are all piano black.

Thanks I was not aware of the GL range I have emailed a couple of stores for price, I wonder if it is any better than the GE.

madcarue

86 posts

Master Geek

#1950120 1-Feb-2018 14:06

Aredwood:

@madcarue Just check the COP Vs temp tables of any heatpump that claims to still have full output even at really low temperatures. Some models have heating elements inside the indoor units, which are used to maintain the output.

That is cheating, do you mean other brands?

mattwnz

19383 posts

Uber Geek

#1950286 1-Feb-2018 19:46

madcarue:

mattwnz:

Are you talking about the GE series, or the GL series?

The GL series is their newer range, and I believe it is called ecoCORE. That appears to be the inbetween range between the hypercore, and the basic GE series. We are looking at the GL series, in the largest size, because they don't do a large hyperCore version.. I also noticed that they advertise they are the quietest heat pumps. However the specs on the Panasonic, shows that it has the same decibel rating. The retail store were pushing really hard for us to go for the Panasonic, and how much better they were, but they didn't sway us.

Would be interested if other people have feedback on the newer GL series, and whether it is worth the extra price difference. Apparently it uses a different refrigerant which is more eco friendly. Just a pity it doesn't yet work with their multisplit system.

Also if anyone has any opinion on the designer series models, I would be interested. I hate white plastic that goes yellow, so was looking at the silver designer series models for a multisplit system. The specs do seem slightly better than the GE series, and they are less bulky looking. Only problem is I can't find anywhere in Wellington that has the silver unit on display, they are all piano black.

Thanks I was not aware of the GL range I have emailed a couple of stores for price, I wonder if it is any better than the GE.

From what I have seen, the specs look slightly better and more efficient, so over time they may save money on power. I think it could eventually be the replacement for the GE, as it uses a far more eco friendly refrigerant. Anyone looking to see the silver unit in Wellington, they have one at their head office in lower hutt, and IMO it is their best looking unit, and being silver hopefully it won't go yellow.

rscole86

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#1950351 1-Feb-2018 21:08

mattwnz: Also if anyone has any opinion on the designer series models, I would be interested. I hate white plastic that goes yellow, so was looking at the silver designer series models for a multisplit system. The specs do seem slightly better than the GE series, and they are less bulky looking. Only problem is I can't find anywhere in Wellington that has the silver unit on display, they are all piano black.

Have you tried contacting Black Diamond Technologies? They're the distributor, and are based in Lower Hutt.

Aredwood

3885 posts

Uber Geek

#1950990 3-Feb-2018 01:30

madcarue:

Aredwood:

@madcarue Just check the COP Vs temp tables of any heatpump that claims to still have full output even at really low temperatures. Some models have heating elements inside the indoor units, which are used to maintain the output.

That is cheating, do you mean other brands?

Mitsubishi have done something different to create a heatpump that can still output it's max rating even at -15deg. Maybe it is by using heating elements, maybe it is just by taking a really large capacity heatpump, and programming it to limit it's peak power output to a lower value. Meaning that it will only ever ramp to max output when the outside temp is -15.

Either way, the larger the difference between the indoor and outdoor temps. The more energy that will be required to move heat between the 2. So the COP tables still need to be consulted.

Also look at its sizing guidelines. Will full output ever be needed when sizing is correct? (heatpump running continuously) Assuming it does have heating elements, maybe they will only ever get used to quickly heat the room. When the heatpump is first turned on in a cold room.

madcarue

86 posts

Master Geek

#1955759 12-Feb-2018 14:22

I have managed a good price on a Mitsubishi R32 GL80 9kw pump and awaiting delivery ideally I wish to place the indoor unit on the wall behind where I sit, is it possible to activate the remote control from a 90 deg angle, if not I will have to put on opposite wall or hang a mirror on the wall to reflect signal.