Most reliable medium sized heatpump for bitter cold day?

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#1055993 29-May-2014 14:54

timmmay: Most wood burners create a draft in from the ceiling cavity. When I took out a freestanding fireplace it made the house much warmer. Of course being without power it'd be useless, so areas where that's common alternate heating is better - I prefer ducted gas to wood, wood makes the whole neighbourhood smell bad.

On chimneys and drafts, has anyone used chimney balloons?

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Batman

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#1056018 29-May-2014 15:28

networkn:
bfginger: A Fujitsu from six years ago is a couple of technical revisions ago. Do the new ones still have the same problems?

I'd rather have a average product with great support than a great product with poor support. Even if they are technically better than they used to be, which I would have my suspicions about, customer care and support is rubbish even as recently as a few months ago, in my experience.

It's no good if it keeps defrosting! Are you in the south island?

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#1056052 29-May-2014 16:16

blakamin:
I have a new 6kW Nocria in a previous house - it stops to defrost around 50% of the time (seriously!)

I have a Fujitsu aswell and even here in mostly mild Napier the damn thing stops quite often to defrost leaving the inside unit blowing colder air around the inside part of the unit is big but I think the outside part is just to small to cope with anythin under 10 degrees

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#1056058 29-May-2014 16:22

ooo yeah forgot about the blowing colder air bit while defrosting - like ... what is the darn thing thinking of!

timmmay

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#1056077 29-May-2014 16:33

My Nocria has never blown cold air when it's meant to be heating. I have the AOTZ24LBT outdoor unit and AWTZ24LBC, rated 7500w cooling and 8500kw heating, a bit more in good conditions I think I read somewhere. It does turn on and off according to the thermostat, and I have no idea if it spends any time defrosting, but the house is always warm. That heat pump is oversized for the area we're heating though - undersizing a heat pump is a good way to reduce efficiency and increase how often it has to defrost.

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#1056079 29-May-2014 16:34

i have a feeling reliable heating depends on the COP. the mitsis and the daikins all have really crap COPs, work amazing. ?

timmmay

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#1056081 29-May-2014 16:37

joker97: i have a feeling reliable heating depends on the COP. the mitsis and the daikins all have really crap COPs, work amazing. ?

I chose the Nocria based on the CoP, at the time it had the best CoP for the heating capacity I wanted. Interestingly the smaller the unit the higher the CoP, but if you get a small unit and it has to work hard all the time it's less efficient. That's why I got the larger unit.

My Nocria outdoor unit is pretty huge, probably 30% larger than my 7kw Daikin.

If I was doing it again I'd probably get one of those double outdoor unit ones and do central heating.

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#1056111 29-May-2014 17:34

How can an outdoor unit need to defrost if it's 9 degrees outside?

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#1056117 29-May-2014 17:50

Because it's cooling the air it will get colder than that, and if it's damp outside that cold will condense water into ice.

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#1056163 29-May-2014 18:49

bfginger: How can an outdoor unit need to defrost if it's 9 degrees outside?

you need to read up on how a heat pump works

if its warming inside its cooling outside and vice versa.

https://www.youtube.com/watch?v=1MiQCBIx1mM

Camden

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#1056226 29-May-2014 20:48

Before I retired a few years ago I was in the heating, ventilating and air con business. My experience was with Fujitsu, good average product, good dealer network and good back up with the importer for spare parts, service problems etc. Hitachi, very good product technically, but very poor back up from Hitachi Australia were the product used to come from. LG, good average product, bit micky mouse as far as distributors and back up went but ok in general. Daikin, very good NZ wide dealer network, good back up from importers and good spare parts, service setup. In my experience Hitachi and Daikin work best in the colder parts of NZ. We have a Hitachi 7.5kw ducted and a 4kw Daikin ducted units in our house and have no problems with not enough heat in the cold Christchurch winters. Also my wife's business has four Daikin and two LG high wall units. Sometimes the LG struggle a bit when it is really cold but the Daikins seem to perform well.

I would suggest you go see an independent dealer and get him to come around and do a heat loss calculation for the area you want to heat and size the unit accordingly. This sort of company will have more experience and knowledge to advise you than if you go to a retailer like HN or NL etc.

Beavis

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#1056234 29-May-2014 21:15

I live in Invercargill. Have had several heat pumps, and the best one by far is a floor mounted Daikin. My present house has a wall mounted Daikin which is not quite as good as a floor mounted one (wee bit drafty), but really quiet and hardly ever defrosts.

Stan

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#1056250 29-May-2014 22:11

I have worked in the heating industry for 6 or so years and I think the notion that Fujitsu are an average brand rather laughable considering they lead the market on technology more than any other brand and push efficiency on there units. What other brand in NZ has a highwall at 7KW+ with a cop of above 4.0?
It it worth noting that the new Fujitsu E3 series do not use R410a refrigerant rather use R32.

Mitsubishi is less efficient than Fujitsu but tend to not frost as much. Nice units would defiantly a brand to consider.

At the end of the day you will find someone with a "horror story" about any brand even very reputable ones.

Go with a mainstream brand and there is a high probability that you will be happy with your purchase.

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#1056252 29-May-2014 22:14

ok how about this - i had 2 nocria (new) 1 daikin (old). both are defrosting 50% of the time on a cold night/day. without fail. anyway, i could have claimed warranty but i have moved to a warmer house. the daikin however ... just keeps pumping the heat ...

can't beat that.

Stan

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#1056253 29-May-2014 22:19

Camden: Before I retired a few years ago I was in the heating, ventilating and air con business. My experience was with Fujitsu, good average product, good dealer network and good back up with the importer for spare parts, service problems etc. Hitachi, very good product technically, but very poor back up from Hitachi Australia were the product used to come from. LG, good average product, bit micky mouse as far as distributors and back up went but ok in general. Daikin, very good NZ wide dealer network, good back up from importers and good spare parts, service setup. In my experience Hitachi and Daikin work best in the colder parts of NZ. We have a Hitachi 7.5kw ducted and a 4kw Daikin ducted units in our house and have no problems with not enough heat in the cold Christchurch winters. Also my wife's business has four Daikin and two LG high wall units. Sometimes the LG struggle a bit when it is really cold but the Daikins seem to perform well.

I would suggest you go see an independent dealer and get him to come around and do a heat loss calculation for the area you want to heat and size the unit accordingly. This sort of company will have more experience and knowledge to advise you than if you go to a retailer like HN or NL etc.

Hitachi back up should be better now as distribution has been taken over by temperzone (old mitsubishi heavy industries importers) in 2012 or so?

Still think mitsi (electric) would be better as far as frosting up is concerned.

Here is my fujitsu after I deliberately made it frost up yesterday morning :) :

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