I'm getting a heat pump - how beneficial would going to double glazing be?

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mmd

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#2442481 20-Mar-2020 21:21

Technofreak:

I fear you will be really disappointed with the heating results if you install the pump as you indicate.

I think you are expecting too much from that pump to adequately heat the downstairs area. Base on our experience with the cooling ability of our pump, if we were intending to stay in our current house long term we would be installing a second pump upstairs.

Another factor to consider is even though you can blow the heated air downwards the heated air will still rise. Also the air being drawn into the heat pump will be warm air rather than cold or colder air if it were mounted lower. Having a heat pump mounted lower rather than higher for heating is a very effective way of mixing all the air in the room and warming the colder air. The converse applies for when the cooling mode is used.

I think you may need to consider two pumps or a ducted system to gain the desired results.

One other thing to consider is the draught created by the airflow from the heat pump. This can be quite annoying for many people, careful location of the pump can minimise the effects of this.

I am not a heat pump expert, my comments are purely based on personal experience. I would urge you to get some good advice on the best location prior to hitting the Go button.

You make some good points.

Do you feel any different about it if I point out that the ceiling slopes up from the windows to the bedroom upstairs? I'm gonna take a stab and say maybe it slope up 400-600mm from the window edge to the opposite edge of the bedroom.

Technofreak

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#2442487 20-Mar-2020 21:29

No I don't think that will make much difference.

I think Jase2985's suggestion of a ceiling fan and locating the heat pump just above the lower windows may be worth exploring, but I'd still get the opinion of a reputable installer.

Like us with our single heat pump you are asking a lot from the heat pump. We should really have two but since heating is our main priority we get away quite nicely with just the one floor mounted model.

Everything is a compromise to some extent, unless you have a big budget. If you end up with one pump you will have to choose which your priority is, heating or cooling.

In my opinion Jase2985's suggestion is a real half way house between the heating and cooling demands. The ceiling fan will certainly help mitigate that.

The size you choose for the pump will also be a big factor in how successful the heat pump is. I would go as big as you can.

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jonherries

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#2442516 20-Mar-2020 23:08

Couple of thoughts:

1.Normally you want sleeping spaces to be cooler than living spaces, leads to an interesting problem/benefit if you put it against the ceiling.
2. You look like you have timber louvers from the picture, I would swap them for a fixed pane if the bod corp allows - they leak a lot of heat and airflow.
3. Double glazing helps with heat loss and keeping you cool too, you can also tint both panes of glass to reduce infrared heat.

I would be tempted to just live in it for the winter and see how you go...

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Handle9

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#2442602 21-Mar-2020 00:17

Heat pumps are great for heating rooms but fairly hopeless for heating houses. You don't get enough BTUs to get much convection happening, you rely on the fan to mix the air.

High wall heat pumps are actually really good at heating you just need to think about positioning and how you set up the diffusers. What you are looking for is airflow in the room to make the air mix.

Floor pumps are good if you have the right room setup which allows it to throw the air across the floor and then rise. If it's obstructed then they don't generally work as well. It's usually easier for a highwall to create this airflow (ceiling consoles are better still but really ugly IMO).

timmmay

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#2442611 21-Mar-2020 06:17

Handle9:

Heat pumps are great for heating rooms but fairly hopeless for heating houses. You don't get enough BTUs to get much convection happening, you rely on the fan to mix the air.

Somewhat agree, somewhat disagree. Two heat pumps heat our whole house, which is old style rather than open plan. In a well insulated house heat easily goes around corners and through doorways if given enough time, but not as much as you might like. We do use oil heaters at night in bedrooms when doors are closed, and in the middle of winter the heat pumps are more "pre heat" (starting say 4pm) with oil heaters coming on maybe 7pm to get the temperature the rest of the way up.

If heat pumps are turned on only when needed right when you get home, rather than pre-heating for a while, you might be right. When our son was very young we left them on all the time, the house felt much much warmer and the power bill in our old but well insulated house wasn't anything remarkable. I didn't do a direct comparison but the power bill wasn't up hugely compared with having them on morning and evening so I didn't feel the need to look into it.

Technofreak

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#2442641 21-Mar-2020 09:24

Handle9:

Heat pumps are great for heating rooms but fairly hopeless for heating houses. You don't get enough BTUs to get much convection happening, you rely on the fan to mix the air.

High wall heat pumps are actually really good at heating you just need to think about positioning and how you set up the diffusers. What you are looking for is airflow in the room to make the air mix.

Floor pumps are good if you have the right room setup which allows it to throw the air across the floor and then rise. If it's obstructed then they don't generally work as well. It's usually easier for a highwall to create this airflow (ceiling consoles are better still but really ugly IMO).

I have to disagree to some extent with your statement on heating houses. Our heat pump does heat our house well, not just one room. I will agree that this is not always the case. One problem is very often a big enough heat pump isn't installed

I don't know what sort of floor pump you're talking about but our one draws in the cold air at floor level and expels warmed air at about a metre above floor level. It doesn't throw the air across the floor.

I agree location is important both from an obstruction point of view and an air distribution point of view. The same can be said about highwall variants though their high mounted location usually means less issues with obstructions. Strategic location in both cases is important. Locating the ideal position for a floor mounted pump can be a challenge in some houses.

I have never experienced a highwall heat pump that heats as well as our floor mounted one. Two other family members have floor mount heat pumps and they all work very very well. YMMY

We probably have almost the ideal set up which is why it works as well as it does.

I still maintain for where heating is a priority a well located floor mounted pump will out perform any high wall mounted heat pump. A floor mounted pump when used for heating is aided in it's job by the fact heat rises and it's sucking in the coldest air to warm up. The air in the room circulates in a natural fashion.

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Stephendnz

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#2490703 24-May-2020 21:05

One thing you might want to consider is DIY double glazing.. I did half our house.. so far, just the south and east side windows.. using perspex.. On one large fixed pane window i just nailed (carefully) a 12mm x 8mm slat up against the existing glass.. on the flat.. then I got the perspex cut to the exact size. +/- 1mm and secured it in place with another slat about the same size.. but size is not critical,.. it's just like a glazing bead..

It actually made a HUGE difference.. I remember the first night.. there was a 6 degrees difference between that room and and a similar sized room next door to it.. no heating in either at the time.. I was right impressed I can tell you.. and totally pleased with the effort. We have really good thermal curtains.. but in winter I open the curtains - usually on a middle of the night loo visit, because i like to have the morning sun wake me - and it's still not too cold.. couldn't do that before adding the perspex.

Did I see in one of your replies that the windows were aluminium.. by the looks of those high windows you have a wooden frame so should be able to do as i did, and are they fixed panes.. just for light? If they are opening windows that's a but more challenging..

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timmmay

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#2490744 24-May-2020 21:15

@Stephendnz there are companies that will do that for you. I did it years ago, cost from memory about $3K, it does work well. I replaced it with proper glazing a few years ago at about $15K, which looks much nicer and has the benefit that since it's PVC doesn't need to be painted.

afe66

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#2490805 24-May-2020 23:13

Does it get cold enough in Auckland to really justify double glazing as early step in warming plan? Someone did a master project on double glazing and not financially viable until you live a fair way down south island

Are you going to leave the curtains open alot? Do you work from home ? In evening, do you plan on leaving the windows open to look at the view?

Otherwise would closing thermal curtains during the day when at work and the evening not be better?

I'd go for a good heat pump and thermal curtains as first line and review after a couple of winters.

You need to factor cost of glass vrs benefit and extra hassle and costs of building Corp getting in the way.

I've spent 25k double glazing a 1920s villa house. Character bay windows are an arse to retrofit. Also have heat pump and underfloor and ceiling insulation. Even with double glazing we close curtains for additional warmth and privacy. (Dunedin)

timmmay

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#2490822 25-May-2020 05:45

We found double glazing made the house feel warmer, even though we already had a couple of heat pumps and other insulation. It's not scientific, but we're glad we did it. It can also be about replacing old windows with something modern that open and close.

GGJohnstone

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#2490940 25-May-2020 10:40

I have placed a normally high mounted heat pump close to the floor. It is extraordinarily capable as a heater as intended.

There are some personality issues with its behavior but all good. The house does not suffer from stratified warmth that might result from high mounting. The personality quirks are probably trying to reduce same. Heat throw is the "BS" term the sales spruikers might use to sell you the second heat pump up stairs to augment the high mounted one down stairs.

neb

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#2491043 25-May-2020 13:38

mmd:
Standard aluminium frames like you'd find in any 2000s house.

You're going to lose heat through the frames, but from the photos the frame to glass ratio is pretty high so it won't make that much difference. Again from that photo, your best option might be decent honeycomb blinds to replace the existing ones, those won't require re-glazing and may even offer better performance than double glazing (I'd have to check the R-values you can achieve).

neb

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#2491046 25-May-2020 13:40

mmd:
Standard single glazing, windows posted above. The only other openings in the apartment are the front door to the apartment itself, as well as a skylight in the ceiling that can be opened. The skylight has a wooden frame (go figure).

Skylights are typically used in Europe where they think about insulation. That one will be double-glazed, with the wooden frame for insulation purposes.

halper86

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#2491123 25-May-2020 15:08

Technofreak:

I don't know what sort of floor pump your talking about but our one draws in the cold air at floor level and expels warmed air at about a metre above floor level. It doesn't throw the air across the floor.

I have a floor-mounted heat pump in my house, Has outlets near the floor and the top with the ability to turn the bottom outlet off.

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