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slofox
17th January 2011, 12:32
Looks like I sold me house. Now I hafta find somewhere else to live. The one I am looking at has no heating but looks a prime candidate for a heat pump - if I can get it cheap enough (the house that is, not the heat pump).

Since I know eff all about heat pumps I thought I wold consult that repository of all knowledge and enlightenment, KIWIBIKER!

So tell me, good people, what I need to know.

Are their differences between brands?

Are there good and bad installers to deal with? (In or around The Tron)

How wildly do prices vary?

What traps are there for the unwary?

How do we know if a quote is realistic or not?

Is there a formula for calculating how many gazillawatts we need?

Thanks in advance for your input. Most useful answer will be showered with bling...

neels
17th January 2011, 12:49
My neighbor who installs them only installs mitsubishi, fujitsu and panasonic, won't touch anything else because he can't be arsed with the phone calls when it doesn't work properly.

A good installer should be able to tell you what size unit you need for the area you want to heat, it's tempting to think they are upsizing to try and get more money out of you, but as above they'd rather err on the larger size so they don't get phone calls when it doesn't work properly.

There are good installers and bad installers, word of mouth and check out their work is the best way to find a good one, although there are fujitsu and mitsi approved ones who should be a step up from the average cowboy.

Scuba_Steve
17th January 2011, 13:15
as above (neels) those 3 brands tend to be the best might be slight more expensive up front than some other brands but they will more than save you in the long run.

Something to consider (as most people don't) is a heat pump WILL cost money to run think most avg an extra 30$/month (this obviously will be highly dependant on usage, temp, room size, ambient temp etc.). But just don't be fooled by their "cheap" running status they are cheaper than alot of other heating options but they are not "cheap".

HenryDorsetCase
17th January 2011, 13:31
Looks like I sold me house. Now I hafta find somewhere else to live. The one I am looking at has no heating but looks a prime candidate for a heat pump - if I can get it cheap enough (the house that is, not the heat pump).

Since I know eff all about heat pumps I thought I wold consult that repository of all knowledge and enlightenment, KIWIBIKER!

So tell me, good people, what I need to know.

Are their differences between brands?

Are there good and bad installers to deal with? (In or around The Tron)

How wildly do prices vary?

What traps are there for the unwary?

How do we know if a quote is realistic or not?

Is there a formula for calculating how many gazillawatts we need?

Thanks in advance for your input. Most useful answer will be showered with bling...

I researched it a bit when we decided we'd had enough of being cold: my focus was on heating for our bedroom, with some extra bonus heating for that end of our house. At the time (18 months ago) the consensus seemed to be either Mitsubishi Electric or Daikin: We got M E because it was thought to be quieter in operation than the Daikin, which was important to us because it was going in our bedroom.

Got a few guys round, and prices (total) didnt vary too much. I was recommended an outfit and they got the job even though they werent the cheapest. They were good, and their installer had a complete nightmare due to some unique features of our house. There was a post-installation problem, and the owner of the business fronted up, said "Yep, we'll sort that shit out for you". And then did. Which I liked a lot.

The extra bonus feature has been that we have been using the thing to cool our house down this summer when its been so frickin hot. Fantastic.

Two things I learned: Make sure your insulation in the new place is up to scratch first: pointless chucking money at a sieve. There are two types of Mitsubishi heat pump: one is I think commercial, and one domestic. think Mitsubishi is commercial and Mitsubishi Electric is domestic.

Take the advice of the people who instal them as to what size you need.

Be conscious that if your entire heating is via this, if you have no power, you have no heating. I found that out one crisp September morning last year.

they are pretty cheap to run, too: so much so that I want to get rid of our gas heater in the other end of the house and replace it with a huuuuuge heatpump. $$$$ though.

HenryDorsetCase
17th January 2011, 13:34
as above (neels) those 3 brands tend to be the best might be slight more expensive up front than some other brands but they will more than save you in the long run.

Something to consider (as most people don't) is a heat pump WILL cost money to run think most avg an extra 30$/month (this obviously will be highly dependant on usage, temp, room size, ambient temp etc.). But just don't be fooled by their "cheap" running status they are cheaper than alot of other heating options but they are not "cheap".

Just as an idea, we have a gas catalytic heater thing in our lounge, which runs through (in midwinter) a 45kg LPG cylinder in about 3 weeks. that is about $30/week for half the house warmed tepidly. tepidly.

steve_t
17th January 2011, 13:39
My installer recommended Daikin for single units or a Panasonic unit to vent the whole house. I decided to do the whole house though it cost shitloads. Hopefully, it adds well to the value of the house.
Anyway, costs do vary wildly so shop around. Try at least both Four Seasons and Eastside Refrigeration for quotes. They'll need a floor plan of the house or at least some dimensions.
Oh, make sure you get an Inverter heat pump - easily worth the slight extra cost :niceone:

Edbear
17th January 2011, 13:48
Who's that ex cricketer guy on the telly? He knows.... :niceone:

steve_t
17th January 2011, 13:49
Who's that ex cricketer guy on the telly? He knows.... :niceone:

I heard Stephen Flemming's Fujitsu heat pumps weren't the most reliable... unsure about how accurate that is

spajohn
17th January 2011, 14:02
While Consumer reports probably deserve a bit of the criticism they get this may be of interest: http://www.consumer.org.nz/reports/heat-pumps

JimO
17th January 2011, 14:39
get a big fuckoff logburner, we have a masport le5000 its our only heating in the middle of winter here it heats my large 2 storey 1910 house no worries with a ceiling fan to push the heat about, we go through around 8m of wood a year buy it around xmas for $70 a cube, and it will work in a power cut. I work on new houses all the time jam packed with heat pumps, people think they are free to run, until they get the bill

Hoon
17th January 2011, 14:49
We got the cricket dude heat pump put in a couple years ago. Best $2500 I've ever spent on the house. Probably costs us an extra $50-100 a month in power though mainly because we don't care. We leave it on 24x7x365 about 18C in summer and 22C in winter. Bonus is no flies or hay fever and not having to open/close windows everytime you get home/go out.

firefighter
17th January 2011, 15:04
I had a flash new Fujitsu in my old place, and even in a small 2 bedroom it cost a fortune to run.

I'd never get one again.

NinjaNanna
17th January 2011, 15:24
Pretty sure my fujitsu has a 7yr warranty, that's what clinched it for me over the equivelant Mitsubishi unit.

While the points already been made though, I'll second that I wouldn't get one if the power in my area was unreliable.

Best part of heat pumps is instant heat and no wood chopping. Oh yeah and reverse cycle can be nice sometimes too.

p.dath
17th January 2011, 16:10
I've had several Daikin's and been real happy with all of them.

Currently I have a larger older unit in the main living area. It is about 8kw. It is maybe 7 to 10 years old, and still going without having to be touched (except cleaning the filters every 6 months, which I do myself). You don't notice it compared to the noise of the TV, but would notice it if everything was off and silent.

I have a smaller 5kw unit downstairs outside all of the bedrooms. I used a smaller unit because it is much quieter. You don't notice is running at all.

I have both units fitted with hepa filters - to get rid of allergens, as one of the children gets allergic reactions easily.

I only run them when it gets cold, or it gets humid (can't sleep). They keep the house nice and dry and mould free as well.


I can't sing there praises highly enough.

HenryDorsetCase
17th January 2011, 16:13
I had a flash new Fujitsu in my old place, and even in a small 2 bedroom it cost a fortune to run.

I'd never get one again.

How much insulation in that house? how much attention paid to draught stopping? was it double glazed?

slofox
17th January 2011, 16:15
Thanks to all for the input.

The place I have just sold had no heating when I went into it. I put in a log burner plus a heat distribution system. Wonderful. But not that cheap since I had no source of "free" firewood and always had to buy from a woodlot. About $600 per year if you bought in the off season and got the summer discount. So that's $50 per month anyway over the course of the year. So I don't think the cost of running a heat pump is any worse than I have been used to.

I still have concerns over power supply - with this system, if the power goes out for any length of time, you're fooked. With the log burner, I could cook on it and stay warm. But, there aren't that many outages here anyway. Course if the earth starts jumping about as in Christchurch, things may be different. Fingers crossed.

Insulation (or lack thereof) is a problem no matter what sort of heating you use. The outside walls of the place I am looking at are clad with split-stone, which is good, but I doubt there is in-wall insulation, it being built circa 1970. Dunno about the ceiling. It's one of these "flat" roof jobs (faux Spanish I suppose - ugliest fuckin' building I have ever seen actually) so there is no real ceiling space. No doubt there's a gap but I dunno how deep or what, if anything, is in there. Probably nothing but air. That is a bridge I will have to cross if I get as far as actually buying the place.

If I can knock the vendor's price back enough, i could free up enough cash to fix quite a few things. Have to wait and see.

firefighter
17th January 2011, 16:18
How much insulation in that house? how much attention paid to draught stopping?

The only draughts of concern would be leading into the bedrooms so not an issue. It's hard to explain but if you saw the house you'd know what i mean. Insulation was fine, I had personally replaced a lot of it.


was it double glazed?

This was in N.Z.......!!! No such thing here!

There was'nt mush heat loss, it was a good heater and air conditioner, but it was just really expensive to run. It's not like we had to leave it on often.

Gone Burger
17th January 2011, 16:21
I have a Daikin in my house - the unit is about 5 years old now, as is the house. Personally, next time I will be going for a different brand. It it rather noisy, even on the hush setting. And living in the Akatarawas can be a very cold region mid-winter. During these times the heat pump became almost redundant as the outside unit would freeze over (yes, it is covered), and the inside unit would pump of luke warm air, even when set to 30 degrees at full force. House has full insualtion and double glazing too. This unit has also proven to be a bit pricey to run, compared to what I have been hearing about other brands.

GREAT to have a heat pump (have just moved into a rental and have been freezing my ass off without it) but from my experience, do shop around. If I buy another house I will be installing one right away.

SMOKEU
17th January 2011, 16:22
A log burner would be a good idea if you have access to free firewood.

Str8 Jacket
17th January 2011, 16:27
A log burner would be a good idea if you have access to free firewood.

The house next door is made of wood....

nosebleed
17th January 2011, 16:31
A log burner would be a good idea if you have access to free firewood.

Air conditioning and heated floors are great if you get free electricity.
Whats your point?

Slofox, PM Choppa

Scuba_Steve
17th January 2011, 16:35
Air conditioning and heated floors are great if you get free electricity.
Whats your point?

Slofox, PM Choppa

free electricity is just an extension cord away... :innocent:

steve_t
17th January 2011, 16:38
Slightly off topic but has anyone had any experience with that faux double glazing that looks like covering your windows in duraseal? Wondering how effective it is

Edbear
17th January 2011, 16:41
Thanks to all for the input.

The place I have just sold had no heating when I went into it. I put in a log burner plus a heat distribution system. Wonderful. But not that cheap since I had no source of "free" firewood and always had to buy from a woodlot. About $600 per year if you bought in the off season and got the summer discount. So that's $50 per month anyway over the course of the year. So I don't think the cost of running a heat pump is any worse than I have been used to.

I still have concerns over power supply - with this system, if the power goes out for any length of time, you're fooked. With the log burner, I could cook on it and stay warm. But, there aren't that many outages here anyway. Course if the earth starts jumping about as in Christchurch, things may be different. Fingers crossed.

Insulation (or lack thereof) is a problem no matter what sort of heating you use. The outside walls of the place I am looking at are clad with split-stone, which is good, but I doubt there is in-wall insulation, it being built circa 1970. Dunno about the ceiling. It's one of these "flat" roof jobs (faux Spanish I suppose - ugliest fuckin' building I have ever seen actually) so there is no real ceiling space. No doubt there's a gap but I dunno how deep or what, if anything, is in there. Probably nothing but air. That is a bridge I will have to cross if I get as far as actually buying the place.

If I can knock the vendor's price back enough, i could free up enough cash to fix quite a few things. Have to wait and see.

I think the Gubbmint has a scheme to insulate houses built before 2000? Ask about it as I think a guy I know up Whangarei got his house insulated for free.

SMOKEU
17th January 2011, 17:15
Air conditioning and heated floors are great if you get free electricity.
Whats your point?

Slofox, PM Choppa

There are many free places to get free firewood legally. All you need is a chainsaw and a trailer.

Morcs
17th January 2011, 19:49
Heatpumps are almost pointless if your house isnt properly insulated or ventilated - and theyll cost you a lot to run because of that.

3 things are required for a healthy dry home: Ventilation, insulation, and heating.

For some reason Kiwis do them in the opposite order, costing them more money as sometimes you only need to go as far as step 1 or 2.

Having worked in the industry on a few sides i know the ins and outs.

To break down the theory a bit:

Ventilation - to dry out your home. Kiwi homes are CRAP, and hold a lot of moisture, A ventilation system such as a HRV or DVS will dry out the home over time and keep it dry - a dryer home is a warmer home, and easier to heat.

Insulation - pretty straight forward. If your home is dry, insulation will keep in any warmth. If your home has no ventilation, itll just keep the moisture in.

Heating - pretty self explanatory - if your home is dry and insulated then youll actually get the benefits here (if your home is still cold enough) and it will be A LOT cheaper to run when combined with the above.

Im not a fan of heat pumps. people have the common misconception that they will dry out a house via heating it - but no what they actually do is just push the moisture to the other end of the house - youll notice parts of your house are nice dry and warm, but the likelehood is, somewhere at the other end of the house will seem cold and damp.

pete376403
17th January 2011, 19:59
I used this http://www.aircondition.co.nz/pump_calculator.htm to calculate sizing and bought a Panasonic 3.5Kw (its only heating one room) $1698 from Hardly Normal not including installation.
Have put the insulation in when regibbing, and replaced the draughty old windows (but not double glazed)
Can't comment on it's performance as not delivered till next Friday.

Matt
17th January 2011, 20:02
We got Daikins installed a couple of years ago and they're awesome - so much cheaper than our old gas fire/oil heaters. We got 4 indoor units (1 in each bedroom) that run off one outdoor unit, and then another one in the lounge/kitchen runs off a second unit.

Best money we've ever spent on the house :niceone:

Oh and we got that Magicseal (secondary double glazing) done on the main bedroom windows but it's a bit crap really, we need to save up and get it done properly!

Matt

steve_t
17th January 2011, 20:05
Oh and we got that Magicseal (secondary double glazing) done on the main bedroom windows but it's a bit crap really, we need to save up and get it done properly!

Matt

That's what I've seen on TV - Magicseal. Crap eh? Good to know:niceone:

Smifffy
17th January 2011, 20:08
I have flued gas central heating, and in a central plateau winter I can dial up the thermostat and sit around in my undies.

Which is really handy cos I pay out the arse for it at the end of the month.

Genestho
17th January 2011, 20:10
I have an HRV which I had installed 3 winters ago and two heat pumps; Panasonic 7or 8? kw inverter (a bit noisy) and a fujitsu 4 or 5 kw? (quiet) inverter installed over the next two consecutive winters, together the whole system is fantastic, HRV keeps the home dry so it takes less energy to heat the air.

The HRV immediatly removed condensation off windows etc, have never had to wipe joinery again!!:niceone:

Home is fully insulated, under a third of the home is double glazed..just have to regularly wash the outside systems with fresh water and change filters.

I did look at a log fire but the whole rigmerole really wasn't appealing, haven't had a power outage in winter...(yet - touch wood - hah)

Power bills are excessive in winter though.. but equate that with alternative heating, less colds/doctors bills and perscriptions, probably evens itself out..

crazyhorse
17th January 2011, 20:15
Looks like I sold me house. Now I hafta find somewhere else to live. The one I am looking at has no heating but looks a prime candidate for a heat pump - if I can get it cheap enough (the house that is, not the heat pump).

Since I know eff all about heat pumps I thought I wold consult that repository of all knowledge and enlightenment, KIWIBIKER!

So tell me, good people, what I need to know.

Are their differences between brands?

Are there good and bad installers to deal with? (In or around The Tron)

How wildly do prices vary?

What traps are there for the unwary?

How do we know if a quote is realistic or not?

Is there a formula for calculating how many gazillawatts we need?

Thanks in advance for your input. Most useful answer will be showered with bling...

I put in a Daikin - Its a big one with an inverter. Got a excellent deal - bout $2800 and goes really good - cools the house down real quick, and heats it up in winter just the same. Have hardly noticed a difference to my power account. But my home is only about 6 years old, so should be well insulated too.

I swear by this one. Good luck John

BMWST?
17th January 2011, 20:33
fact.heat pumps are efficient,you get more heat out of em than the electricicty you put in.They are the most efficient form of heating.The only way you can compete with a heat pump for heating is a pellet burner,or if your firewood for a log burner is free or cheap(consumer).The reason heat pumps become expensive is that people change their habits.Ie set it to come on in the morning and or evening,and start using it to cool as well.
They cool or heat by blowing heated or cooled air.Be careful with siting the indoor unit some people dont like moving air near them.
A ventilation system is a good purchase,the day after we put ours in the condensation on the windows was gone.You can get ventilation systems that can transfer heat around the house and also get a system to bring air directly from outside to help cool the house in summer.The ventilation systems make our house hotter in summer blowing the 28 c plus air form the roof space.It shuts down at 28 so will be looking at the outside air option.
As an aside i would not buy a flat roof house.one day it WILL leak and as you say you cant really fit insulation or a hrv type system.
The classic house shape has been developed cos it works.....
/rant off

Mully
17th January 2011, 20:37
My (sort-of) cousin owns a company in Auckland that does HVAC and whatnot.

He's getting us a full-noise ducted bells-and-whistles system (at COST!!) when we build, later this year.

Along with high-spec insulation, double glazing and whatnot, we should be sweeeeet.

His advice:
Any of the Japanese brands are great - anything else be wary of.
You need (as mentioned) good insulation. He was ambivalent about HRV and whatnot, but admitted they were a great retrofit to an existing house.

porky
17th January 2011, 21:28
They are in fact a reversable "fridge" with a fan. This principle is called the mechanical refrigeration cycle. An evaporator, condenser and compressor and a reversing valve with something like R22 (monochloridifluoromethane.... i think thats what the shits called but are prepared to stand corrected) coursing thru its veins, changing state from a liquid to gas and back again. To maximise efficiency and lower cost in the heating the installation of heat sinks give a better bang for ya buck. Design is important or you will chuck away good money. There is a formula Kw per sqm, but as mentioned insulation, not just the pink shit in the walls and roof plays a part as does glazing area.... especially south facing, floor material, carpet stud height etc. the best system is the commercial ventilation and air conditioning system that conditions part of the stale air with a quantity of fresh and modifys the humidity. These simply suc and blo, as the temp rises moisture is held in suspension and as the air cool forms as condensation. Buy a big fuck off log burner and leave the window open, heat and ventilation. Shagging in front of the heat pump dosnt really cut it.

Grumph
18th January 2011, 10:33
[QUOTE=porky; Shagging in front of the heat pump dosnt really cut it.[/QUOTE]

Dead right mate....

location in NZ has a lot to do with how happy you'll be with a heat pump. Further South or higher you go the harder the HP has to work hence the higher the cost of running. Most of ChCh is marginal cost/efficiency unless you're lucky enough to have a very well insulated house - and HD Case is the only person I've heard of running one in the summer down here.
If we come out of the quake washup with a new house it'll have log burners fer sure.

porky
18th January 2011, 16:46
Dead right mate....

location in NZ has a lot to do with how happy you'll be with a heat pump. Further South or higher you go the harder the HP has to work hence the higher the cost of running. Most of ChCh is marginal cost/efficiency unless you're lucky enough to have a very well insulated house - and HD Case is the only person I've heard of running one in the summer down here.
If we come out of the quake washup with a new house it'll have log burners fer sure.

And if you do, go for a 22kw unit ( for approx 200sqm house) with a 4kw coil (back boiler ) hooked into a Harris or similar mains pressure HW cylinder. They are s/s liner with a calorifier inside (the old wet back system up graded to mains pressure but with a closed loop- heating water dosnt end up at the tap- just goes from fire to hw vessel and back again at low pressure, sort of the same as the commercial systems you would find in places like hospitals.) Most efficient use of energy. One day i will get anal and sit down and prove with numbers that the electric string isnt that flash for heating.... you pay for conveience.... bit like cell phones. Marketing is king...... Only prob is, chch probably wants the eco flue etc under their District plan unless you are on a 2+ ha property. You will need to check it out.

steve_t
18th January 2011, 17:14
One day i will get anal ... You will need to check it out.

:chase::bleh: