[mdp2021]

> with good ventilation

Mandate windows?!

> heat pumps

That means (if I understand you correctly), fans. That is noise pollution - some will not have it, and some will not bear it. And (after experience), heat pumps can be inadequate for heating: they can raise a temperature, not warm the environment.

[elric]

You're wrong on both counts.

Windows don't make for very good ventilation. They are prone to letting in either too much or too little air, which means you're either wasting a lot of heat, or are not getting enough fresh air. Mechanical ventilation with energy recovery is far superior. Windows, of course, are great for letting in natural light and for creating a sense of spaciousness etc.

Heat pumps don't always need big fans, only air source heat pumps do, and even those can be made to be pretty quiet. Not much louder than a gas furnace.

They definitely can warm an entire house (in fact, they do so on a regular basis in many houses in many parts of the world), even in the coldest of climates. Heating a Passivhaus requires only a tiny unit (except for hot water, but let's ignore that for a minute).

[mdp2021]

> Windows don't make for very good ventilation

The point was not with ventilation quality, but with the feasibility and compromises of alternatives. (The strict point was with defining "mandating good ventilation".) Mechanical ventilation with energy recovery may be far superior, but if that means constant noise it will be an issue - to some, a radical issue.

> They definitely can warm an entire house

And I have stated that they can be perfectly inadequate and ineffective (explicitly: which is not contradicted by your statement). Evidently, it will depend on implementation, and again on the expected effect (where temperature is only a partial factor).

Speaking of implementation, I have been in hotels where the heating pumps were unbearable in that they made the room tremble and clearly vibrate.

So, when one speaks of mandating technologies, there are critical implementational issues to be remembered, and the "embrace" drive is to be immediately criticized (just applying one's usual duly Reflection). It is relevant that I have seen in the past legislation mandating some technologies only halfway trough (e.g. mandating valves without mandating pressure control systems), creating immense damages on large territories.

Edit: also:

> Heat pumps don't always need big fans ... Not much louder than a gas furnace

You have not stated they are perfectly silent, 0db - in fact, you seem to suggest the opposite. As said, some do not tolerate background noise.

I do not see where you read anything wrong.

[empiricus]

"Mechanical ventilation with energy recovery may be far superior, but if that means constant noise it will be an issue - to some, a radical issue." I've installed this in my house, it is virtually silent. This is for ~200m3 of clean air/hour. If I turn it on higher you can hear it a little.

[mdp2021]

> virtually silent

Decibels?

I have seen air purifiers publicized as exemplary silent, and people unable to bear the noise of the minimum fan speed.

There may also be a matter of the exact sound - maybe some are less disturbed by (say) a hum instead of a hiss; it probably has to be tried.

[rsynnott]

While I don't have mechanical heat recovery ventilation, I've been in lots of apartments and houses that do (it's virtually mandatory for new builds here). You won't know it's there unless you're in the room that the device lives in, and even then it's not loud.

[adev_]

> That means (if I understand you correctly), fans.

It does not always means fans.

Geothermal or aquathermal heat pumps are fan-less, very silent and performs amazingly in cold climate. I have one home.

[perceptronas]

Windows>

Heat exchangers can be up to 90% effective at saving heat, while window ventilation will be 0%.

Noise pollution>

In my cold climate, whoever goes with heat pumps - they usually go with "air-water" systems. Meaning only outside you have fans and inside you have your typical floor heating.

[dx034]

Much higher than 90%. The one I had in the passive house I lived in was specified to 98% at most temperature ranges. I guess most of the time the temperature difference isn't that large anyway (<20C) so they will lose next to no heat.

[jaclaz]

A well insulated house needs some sort of mechanical ventilationm otherwise you will have problems with humidity and - in worst cases - mould.

The ventilating units are usually placed in the basement and are not noisy (but need some maintenance and cleaning).

There are heat pumps that simply heat water and are suitable for underfloor heating, no fans.

Underfloor heating is usually "slower" (compared to air heating) but works just fine, actually better.

[patrickk]

Modern air or ground source heat pumps tend to be quiet, even silent, at least according to some deep dives down the Youtube rabbit hole on passive houses. Check out the "Moonstone house" on Youtube for example.

https://youtu.be/sSE8PurhfQs

[dx034]

My neighbour has a air heat pump for a ~200m2 house with good insulation, but not a passive house. It's at the edge of his property so I regularly pass it. I'd say you need to be less than a meter away to hear it at all, and even then it sounds like a fan. There's absolutely no vibration or so.

However, the house is new, let's see how it the unit sounds in 5-10 years.

[tpxl]

We have a heat pump from ~2008 about a meter away from the outer wall of the house and I don't recall ever hearing it from the inside. You'll hear it from a few meters on the outside, but it has never been a problem. It's able to heat a ~250m2 house in -10°C weather.

That being said, do yourself a favor and do not get a heat pump connected to 'the cloud'. Our heat pump can't be fully controlled locally (some functionality is web only) otherwise I'd put it offline. They unnecessarily performed repairs on the heat pump to the tune of 500€ because their servers had issues.

[mcot2]

A heat pump can be air source or geothermal and you can use them to create hot water for a hydronic system or forced air (ducted or non-ducted). So not all of those will create the same noise levels. As they can be virtually any size and now work well at very low temps, I don’t see how they can be inadequate for heating. I’d have to hear of an example.

Up in the Northeast U.S. they are still putting oil fired boilers in new homes since gas isn’t super common outside of larger cities. I’d like to see more new homes have solar, heat pumps and possibly even stationary batteries in the future. These are going to be essential if we want to get off fossil fuels.

[dx034]

If you ventilate purely via windows, you'll need to always pay attention to avoid any mould. With a ventilation system hooked up to a heat exchanger, there's basically zero chance you'll ever experience mold.