Heat-pumps ?

[Dave Ross]

#3010

I am considering whether we should have a heat-pump installed. We have been using an unflued gas heater for a number of years now.  I now realize that these things are not the best solution. What is your experience with heat-pumps? Are you happy with yours? Is there any advice you can give us? We are in Auckland.

[Nico Linde]

#12320

If you do invest in a heat pump dont turn it off at nights , leave it going set on around 16 or 17 degress and then when you get up in the morning then you can raise the temp to say 20 degress , this way you use way less power and time to feel warm and you dont use as much power  which will keep your $ cost down, it will cost you about $2.00 aday for a 24 hour preiodNOD

[Arne Rohde]

#12321

IMHO a heat pump is far superior to an unflued gas heater. Get a reputable brand with a reputable company and installer for support. There's little difference between the efficiency and noise levels of the main brands. Get the company to calculate the size and type of unit you'd need, with an on-site visit. Location, room size, insulation, etc make a difference to how much heat output is required. Placement and noise level of the outdoor unit can make a difference to how your neighbours perceive you.You can get units now that will detect if anyone is present in the room, and if there's no movement they will turn down the temperature. This may or may not be useful, depending on how much you move around.

[Jim Young]

#12322

We had one installed two years ago and it is one of the best things we have ever bought for the house.Like Arne says get a proper inspection and quote for your house, when we got ours measured we were getting towards the top of the capacity scale for one unit so went a size bigger to save it working it's little butt off and the cost increase for the bigger size was minimal.

[Alan]

#12323

No doubt you read the latest Consumer write-up on this?!Not much more to add other than to emphasize:- Get at least the size of heat pump calculated for your dwelling, or one size bigger.  The cost difference is minimal (installation cost doesn't vary whether you install size 1 or 2) but the efficiency is greater if the unit isn't maxed out most of the time- Most folk get an inside unit which is mounted close to the ceiling because it doesn't interfere with their current furniture placement.  This is actually an air-conditioning unit for which 90% of the heat-pumps are manufactured.  Due to our climate (mild winters and cool summers) NZ is unique in that we are using heat pumps mainly for heating rather than cooling.  So the ceiling mounted inside unit is only a compromise for heating.  As heat rises naturally, the machine tries to force the hot air downwards , while only partially successful, this causes a nasty draught, which makes a high-mounted inside unit unsuitable near seating or other areas where people congregate.  If you can at all accommodate it, try and get a low-mounted inside unit; as you will know, in Europe all heating devices are installed low.- Trying to justify the economy of a heat-pump using payback or more sophisticated methods is tricky at best.  Too much depends on future power price movements.  I believe a wood-fire comes up pretty good in terms of cost and carbon-neutrality, but alas it is not legal any longer in my home town as well as in other places around the country struggling with keeping particulate matter out of the air.If NZ can move towards entirely renewable electricity generation, heat-pumps are a good choice.  But with the current government, the trend towards electric heating and soon electric transport, I don't like the chances.  You'll have to do your own figures if that's important to you.- The convenience of heat-pumps is hard to beat.  I'm not sure that I agree with NOD that keeping the machine on all night is always cheaper than starting it up in the morning.  It depends on your usage patterns.  If you or someone else is in the house all day it may well be more economical to keep the pump going all night (how well insulated your place is is also a factor in this decision!).  But if you don't require a warm place after, say 9 am, because everyone is gone, I wouldn't leave the heat pump going all night.  You see, unlike many other slow heating equipment, a heat pump mainly heats the air and is a such very quick.  From the moment you hit the ON button is feels warm within minutes, which is great in the morning.  However, your furniture, walls and floor will be cold.  If all you do is have breakfast and leave, a short, sharp blast from the heat pump is the most efficient way and more convenient that any other heating I know.- Whatever you do, if you have a handful of grands up your sleeve, don't spend it on heating if your insulation isn't up to scratch!  In order of priority:1 Insulate the ceiling (easy)2 Insulate doors/windows (moderate)3 Install suitable heating (easy)4 Insulate walls (tricky)5 Insulate floor (sometimes tricky)My 2 cents worth.Matthias

[Dave Morris]

#12324

No doubt you read the latest Consumer write-up on this?!Not much more to add other than to emphasize:- Get at least the size of heat pump calculated for your dwelling, or one size bigger.  The cost difference is minimal (installation cost doesn't vary whether you install size 1 or 2) but the efficiency is greater if the unit isn't maxed out most of the time- Most folk get an inside unit which is mounted close to the ceiling because it doesn't interfere with their current furniture placement.  This is actually an air-conditioning unit for which 90% of the heat-pumps are manufactured.  Due to our climate (mild winters and cool summers) NZ is unique in that we are using heat pumps mainly for heating rather than cooling.  So the ceiling mounted inside unit is only a compromise for heating.  As heat rises naturally, the machine tries to force the hot air downwards , while only partially successful, this causes a nasty draught, which makes a high-mounted inside unit unsuitable near seating or other areas where people congregate.  If you can at all accommodate it, try and get a low-mounted inside unit; as you will know, in Europe all heating devices are installed low.- Trying to justify the economy of a heat-pump using payback or more sophisticated methods is tricky at best.  Too much depends on future power price movements.  I believe a wood-fire comes up pretty good in terms of cost and carbon-neutrality, but alas it is not legal any longer in my home town as well as in other places around the country struggling with keeping particulate matter out of the air.If NZ can move towards entirely renewable electricity generation, heat-pumps are a good choice.  But with the current government, the trend towards electric heating and soon electric transport, I don't like the chances.  You'll have to do your own figures if that's important to you.- The convenience of heat-pumps is hard to beat.  I'm not sure that I agree with NOD that keeping the machine on all night is always cheaper than starting it up in the morning.  It depends on your usage patterns.  If you or someone else is in the house all day it may well be more economical to keep the pump going all night (how well insulated your place is is also a factor in this decision!).  But if you don't require a warm place after, say 9 am, because everyone is gone, I wouldn't leave the heat pump going all night.  You see, unlike many other slow heating equipment, a heat pump mainly heats the air and is a such very quick.  From the moment you hit the ON button is feels warm within minutes, which is great in the morning.  However, your furniture, walls and floor will be cold.  If all you do is have breakfast and leave, a short, sharp blast from the heat pump is the most efficient way and more convenient that any other heating I know.- Whatever you do, if you have a handful of grands up your sleeve, don't spend it on heating if your insulation isn't up to scratch!  In order of priority:1 Insulate the ceiling (easy)2 Insulate doors/windows (moderate)3 Install suitable heating (easy)4 Insulate walls (tricky)5 Insulate floor (sometimes tricky)My 2 cents worth.Matthias

that was $ worth of worth while information

[Dave Ross]

#12325

Yep, that's what I thought, too. I am getting a good deal. 🙂

[Dave Ross]

#12326

Thanks for all the responses, they are most helpful. We will have to get in some quotes now. The walls in the old part of the house aren't insulated, but the ceilings and floors are. However, it is still a couple of degrees cooler than the newer extension. We'll see how a heat pump copes with this.

[Dave Morris]

#12327

Option H. eat lots of baked beans

[Robin]

#12328

Hey guys, just found this thread.We have right now, 3 quotes to choose from, for heat pumps. - Well, last one is due now. But 2 quotes were more or less the same, but with different brands of units. The different sales reps all push their own favourite brand, and poo-poo the others. Make your own mind up there by doing your own research. We have our own preferred brand. Apparently the compressor in the outdoor unit is only made by a couple of factories, so the H/Pump companies buy from them, and essentially use the same components. (Something like Lucas supplied electrical parts to all different car manufacturers.) We think a ground mounted outside unit is better than a wall (brackets) mounted option, as any motor noise & vibrations will not permeate through the walls into the house interior.

[Warren]

#12329

You are right about wall mounts. At my last house the external unit was wall mounted on brackets attached to a brick veneer wall. The internal noise was not intrusive but you could hear it. At this house, the unit is ground mounted on a wooden base and it cannot be heard.Be sure to get an Electrical Certificate of Compliance.Check the operation of the remote controller as not all are user friendly.P

[dave.valma]

#12330

Have a look on Consumer, they have a data base of over 80 different models. 😀 😀

[Richard Kuysten]

#12331

If you haven't already committed to an installation Alex this might be worth a look:http://www.dvs.co.nz/index.php/pi_pageid/162?gclid=CPXileOXmpsCFQk_agodvGuxBgNot sure of the fine print but could save you a few dollars for gas.Malcolm

[Dave Morris]

#12332

If you haven't already committed to an installation Alex this might be worth a look:http://www.dvs.co.nz/index.php/pi_pageid/162?gclid=CPXileOXmpsCFQk_agodvGuxBgNot sure of the fine print but could save you a few dollars for gas.Malcolm

hey Malcie. Alex and I have previously talked about these. I have a Smartvent system which is similiar to DVS and in the winterless Waikato is great. 12 degrees here in the Waikato today and ceiling cavity peaked at 22c heating the rest of house to this temp. Used to come home to a cold house and now 22c. It is great. Less Moisture etc  They are also installing them in new houses to as a standard feature from some home building companies. generation homes etcAlex has a tile roof and we are unsure on what the heat build-up is like in roof cavity compared with my tin roof. ????????

[Warren]

#12333

Also need to check that the roof has an underlay. My tile roof has not and it is not very warm up there.

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