Central heating vs heat pumps.

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#1821910 13-Jul-2017 14:24

With bottled gas (45kg x2) and trying to heat one floor (120m2) with heated and ducted fire place would work out okay? Or does it need a city connection? I wonder how long it would last if we have it on every day... (12 hours / day)

old3eyes

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#1821913 13-Jul-2017 14:26

I just got this week my first bill since the gas central heating was turned on again. Have only been in the house 3 moths. It was $420 after discount. Jut about died.

Breakdown Power $167.37 441 KwH

Gas $279.14 2516 KwH

Combined bill last month was $234.

Needless to say the auto on / off settings have been change and the heat turned down a bit. If I was building a house I would never have gas as it's too expensive these days. i.e power line rental for month $9.67 , gas $33.92

Our Tauranga house has two Fuji aircon units and the monthly bill is about $160 for this time of year.

Regards,

Old3eyes

cadman

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#1821931 13-Jul-2017 14:54

timmmay:

MikeAqua:

That's true but we only ran our heatpumps when we were home. Too expensive to run them all day.

What they don't do very well is circulate between rooms. The ventilation system did great job of circulating heat into the rest of the house. So at 2pm on a sunny day in winter when the lounge could get uncomfortably hot the ventilation would spool up and heat would be sent to the colder rooms via direct circulation and via the air-air heat exchanger. The whole house might equilibrate to 18C - without running any heating device.

We haven't found it all that much more expensive to run 5am to 9pm as opposed to 5am to 7am and 4pm to 9pm. Yes, more, but not near double. I worked it out the other day but I can't remember what I found, other than it not being so bad. Because the house never gets all that cold it doesn't have to work all that hard to heat the place.

That's because they're spending more time in their higher CoP range while merely maintaining temperature by replacing small losses rather than trying to rapidly heat from cold twice a day.

mdf

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#1821985 13-Jul-2017 15:41

old3eyes:

I just got this week my first bill since the gas central heating was turned on again. Have only been in the house 3 moths. It was $420 after discount. Jut about died.

Breakdown Power $167.37 441 KwH

Gas $279.14 2516 KwH

Combined bill last month was $234.

Needless to say the auto on / off settings have been change and the heat turned down a bit. If I was building a house I would never have gas as it's too expensive these days. i.e power line rental for month $9.67 , gas $33.92

Our Tauranga house has two Fuji aircon units and the monthly bill is about $160 for this time of year.

Out of interest, how does the gas house compare to the electric house in terms of location and insulation? In Wellington, we've found gas overall cheaper, and certainly more pleasant (continuous hot water and fast heat up).

timmmay

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#1821989 13-Jul-2017 15:46

cadman:

That's because they're spending more time in their higher CoP range while merely maintaining temperature by replacing small losses rather than trying to rapidly heat from cold twice a day.

Exactly. I thought it would be more, but the extra cost isn't really all that much. I might work it out properly some time.

old3eyes

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#1822006 13-Jul-2017 16:00

mdf:

old3eyes:

I just got this week my first bill since the gas central heating was turned on again. Have only been in the house 3 moths. It was $420 after discount. Jut about died.

Breakdown Power $167.37 441 KwH

Gas $279.14 2516 KwH

Combined bill last month was $234.

Needless to say the auto on / off settings have been change and the heat turned down a bit. If I was building a house I would never have gas as it's too expensive these days. i.e power line rental for month $9.67 , gas $33.92

Our Tauranga house has two Fuji aircon units and the monthly bill is about $160 for this time of year.

Out of interest, how does the gas house compare to the electric house in terms of location and insulation? In Wellington, we've found gas overall cheaper, and certainly more pleasant (continuous hot water and fast heat up).

Yes the continuous gas hot water is great and so is the gas central heating system,. As far as insulation goes both the Tauranga and Morrinsville houses are of similar vintage 14 ~ 20 years and when closed up feel about the same though Morrinsville has a DVS system as well.

Regards,

Old3eyes

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mdf

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#1822015 13-Jul-2017 16:10

old3eyes:

mdf:

old3eyes:

I just got this week my first bill since the gas central heating was turned on again. Have only been in the house 3 moths. It was $420 after discount. Jut about died.

Breakdown Power $167.37 441 KwH

Gas $279.14 2516 KwH

Combined bill last month was $234.

Needless to say the auto on / off settings have been change and the heat turned down a bit. If I was building a house I would never have gas as it's too expensive these days. i.e power line rental for month $9.67 , gas $33.92

Our Tauranga house has two Fuji aircon units and the monthly bill is about $160 for this time of year.

Out of interest, how does the gas house compare to the electric house in terms of location and insulation? In Wellington, we've found gas overall cheaper, and certainly more pleasant (continuous hot water and fast heat up).

Yes the continuous gas hot water is great and so is the gas central heating system,. As far as insulation goes both the Tauranga and Morrinsville houses are of similar vintage 14 ~ 20 years and when closed up feel about the same though Morrinsville has a DVS system as well.

Gee, that's a pretty 1:1 comparison. I'm surprised that there's that much of a price difference between gas and electricity - that might well settle the which is cheaper question. I guess heat pumps are more efficient the further north you go? And maybe Tauranga might be a little more temperate because of the proximity to the ocean?

MikeAqua

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#1822019 13-Jul-2017 16:20

cadman:

timmmay:

MikeAqua:

That's true but we only ran our heatpumps when we were home. Too expensive to run them all day.

What they don't do very well is circulate between rooms. The ventilation system did great job of circulating heat into the rest of the house. So at 2pm on a sunny day in winter when the lounge could get uncomfortably hot the ventilation would spool up and heat would be sent to the colder rooms via direct circulation and via the air-air heat exchanger. The whole house might equilibrate to 18C - without running any heating device.

We haven't found it all that much more expensive to run 5am to 9pm as opposed to 5am to 7am and 4pm to 9pm. Yes, more, but not near double. I worked it out the other day but I can't remember what I found, other than it not being so bad. Because the house never gets all that cold it doesn't have to work all that hard to heat the place.

That's because they're spending more time in their higher CoP range while merely maintaining temperature by replacing small losses rather than trying to rapidly heat from cold twice a day.

In our situation they weren't heating from cold in the evening because we had a sunny well insulated and sealed house with air circulating warmth throughout. The heat pumps (no ducted) could only circulate heat within a room.

I did try it both ways and it was about 30% more expensive to run them all day. Not bad for double the time, but still more expensive overall.

Mike

Aredwood

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#1822170 13-Jul-2017 22:24

old3eyes:

I just got this week my first bill since the gas central heating was turned on again. Have only been in the house 3 moths. It was $420 after discount. Jut about died.

Breakdown Power $167.37 441 KwH

Gas $279.14 2516 KwH

Combined bill last month was $234.

Needless to say the auto on / off settings have been change and the heat turned down a bit. If I was building a house I would never have gas as it's too expensive these days. i.e power line rental for month $9.67 , gas $33.92

Our Tauranga house has two Fuji aircon units and the monthly bill is about $160 for this time of year.

Your gas bill is only expensive because you used heaps of gas. If you didn't have gas, but instead used the same total amount of energy as electricity. You would have used 2957KW/Hr of power. Lets be generous and assume that you would be on a standard user plan instead of low user. And that your electricity per unit price as a result was 16c per unit. Your bill would have been 473.12 + lines charges. Standard user lines charges will be approx $50 per month. So your total bill for the month if you didn't have gas would instead be $520. So more than double your actual bill of $234. And that is a best case scenario. You could easily have $760 per month power bills with that much electric only usage.

So instead of complaining about gas being expensive, you should instead figure out why you are using so much gas. Your usage is the equivalent of 3.3KW burning 24/7. What model gas central heater do you have? As it could be a ridiculously old and inefficient model. And do you have any gas fires? As there are lots out there that are only approx 10% efficient. As they are not intended to be used for heating. Only to give you flames to look at.

Also your electricity line rental is only cheap because it is a low user rate line rental. If you use more than 8000 units / year or 666 units per month. It will be cheaper to start paying higher line rental fees, so you can get a lower per unit cost for electricity.

Technofreak

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#1822207 14-Jul-2017 07:23

The way I read it the monthly bill old3eyes was talking about was $446.51 ($167.37 + $279.14) and not the $234 which was the previous months bill.

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smalltrader

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#1822212 14-Jul-2017 08:06

Aredwood:

old3eyes:

I just got this week my first bill since the gas central heating was turned on again. Have only been in the house 3 moths. It was $420 after discount. Jut about died.

Breakdown Power $167.37 441 KwH

Gas $279.14 2516 KwH

Combined bill last month was $234.

Needless to say the auto on / off settings have been change and the heat turned down a bit. If I was building a house I would never have gas as it's too expensive these days. i.e power line rental for month $9.67 , gas $33.92

Our Tauranga house has two Fuji aircon units and the monthly bill is about $160 for this time of year.

Your gas bill is only expensive because you used heaps of gas. If you didn't have gas, but instead used the same total amount of energy as electricity. You would have used 2957KW/Hr of power. Lets be generous and assume that you would be on a standard user plan instead of low user. And that your electricity per unit price as a result was 16c per unit. Your bill would have been 473.12 + lines charges. Standard user lines charges will be approx $50 per month. So your total bill for the month if you didn't have gas would instead be $520. So more than double your actual bill of $234. And that is a best case scenario. You could easily have $760 per month power bills with that much electric only usage.

So instead of complaining about gas being expensive, you should instead figure out why you are using so much gas. Your usage is the equivalent of 3.3KW burning 24/7. What model gas central heater do you have? As it could be a ridiculously old and inefficient model. And do you have any gas fires? As there are lots out there that are only approx 10% efficient. As they are not intended to be used for heating. Only to give you flames to look at.

Also your electricity line rental is only cheap because it is a low user rate line rental. If you use more than 8000 units / year or 666 units per month. It will be cheaper to start paying higher line rental fees, so you can get a lower per unit cost for electricity.

I am with Aredwood. You need to look at why you are using so much gas. How well insulated is your house. What temperature did you set the central heating at?

I have 4 bedrooms, 195 Sq Metres. Gas Central heating ducting to every room including kitchen, lounge and bathrooms. Temperature is set at 21C. Reasonably well insulated with double glazing etc, but as a wooden house some wind will always come through.

Winter gas bill average is about $200 for gas central heating, gas hot water and gas cooking. By my own calculation, if this is electricity, the bill will double easily.

Gas can be very economical. The trick is to use gas for everything.

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kryptonjohn

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#1822218 14-Jul-2017 08:19

Aredwood:

And do you have any gas fires? As there are lots out there that are only approx 10% efficient. As they are not intended to be used for heating. Only to give you flames to look at.

Had a gas fireplace in our previous house, with an optional electric fan. With the fan off, it was an ornament and pretty much nil warming effect. Fan on and it warmed the room pretty good. Can't believe the fan was an option!

old3eyes

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#1822251 14-Jul-2017 09:14

Aredwood:

old3eyes:

I just got this week my first bill since the gas central heating was turned on again. Have only been in the house 3 moths. It was $420 after discount. Jut about died.

Breakdown Power $167.37 441 KwH

Gas $279.14 2516 KwH

Combined bill last month was $234.

Needless to say the auto on / off settings have been change and the heat turned down a bit. If I was building a house I would never have gas as it's too expensive these days. i.e power line rental for month $9.67 , gas $33.92

Our Tauranga house has two Fuji aircon units and the monthly bill is about $160 for this time of year.

Your gas bill is only expensive because you used heaps of gas. If you didn't have gas, but instead used the same total amount of energy as electricity. You would have used 2957KW/Hr of power. Lets be generous and assume that you would be on a standard user plan instead of low user. And that your electricity per unit price as a result was 16c per unit. Your bill would have been 473.12 + lines charges. Standard user lines charges will be approx $50 per month. So your total bill for the month if you didn't have gas would instead be $520. So more than double your actual bill of $234. And that is a best case scenario. You could easily have $760 per month power bills with that much electric only usage.

So instead of complaining about gas being expensive, you should instead figure out why you are using so much gas. Your usage is the equivalent of 3.3KW burning 24/7. What model gas central heater do you have? As it could be a ridiculously old and inefficient model. And do you have any gas fires? As there are lots out there that are only approx 10% efficient. As they are not intended to be used for heating. Only to give you flames to look at.

Also your electricity line rental is only cheap because it is a low user rate line rental. If you use more than 8000 units / year or 666 units per month. It will be cheaper to start paying higher line rental fees, so you can get a lower per unit cost for electricity.

The only reason we are using gas is that it's winter and the house has central heating. If we had heat pumps it would be way more cheaper as it is in Tauranga. I would never have gas again . Even before winter te gas bill was expensive compared to what we used (hot water) because of the rip off line charges..

Regards,

Old3eyes

old3eyes

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#1822253 14-Jul-2017 09:16

Technofreak:

The way I read it the monthly bill old3eyes was talking about was $446.51 ($167.37 + $279.14) and not the $234 which was the previous months bill.

The total bill was $464.51 minus discount of $46.45 = $420.06

Regards,

Old3eyes

MikeB4

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#1822361 14-Jul-2017 11:25

We are currently going through this execise right now. We own a Lockwood home that has high vaulted ceilings all wood. We are looking at replacing the heating in the living areas which are a kithen dinning room and a seperate lounge. The lounge is around 64 square meters and the kitchen dinning around 50 square meters.
The heating in place now is a log burner in the dinning room which is about 15years old and in the lounge is a Rinnai radiant flued reticuated gas heater about 10 years old.The gas heater seems to have lost some of its power this winter and the log burner due to my disability is becoming too difficult for me to manage when my wife is away. And my condition requires that I stay warm with dry environment due to my very compromised immune system.

We have looked at various Heat Pumps, gas heaters and central heating. We had a price for hot water radiators with gas furnace of $18,000 installed which we thought was crazy for heating even though they are very good.
With heat pumps we have reached a point of confusion and it is very hard to get unbiased advice on the subject. Would High wall or floor mount be better? In the lounge a floor mount seems a possibility as it could go where the Rinnai is as there is already a hole in the wall but would a floor mounted unit work with high vaulted ceilings? Do we get a unit with one outside unit and separate inside units or would we need separate outside units?

Another option is new gas heaters such as the type that Rinnai sell like the Rinnai Energy saver 559FT https://rinnai.co.nz/home-gas-heaters . There is the option of ducted under floor gas heating but the clearing under the home is very limited and I am not sure the unit would fit.

We have also considered the option of electric panel heating but this would seem quite expensive to run.

We have reached a point of confusion and have no idea what way we should go, any advise the fine folks here could give would be greatly appreciated.

Here is a crazy notion, lets give peace a chance.

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