hvac or multisplit?

[Prometeo]

I wonder which of the two systems is better, there are pros and cons in both cases, Furthermore, how should an HVAC be managed in bathrooms?

 

[stoveliker]

That depends on what you value.

The mini split I have is more efficient than the (2013 or so) central HVAC system I had before. Lower losses because no leaking air too .

But the coil assembly visible in the rooms. But no big (metal duct) rumbling air flow.

I am not aware of people having mini splits in bathrooms. We did have a ducted HVAC register in the bathrooms back in TN.
Just an exhaust fan and window is used now for moisture control.

 

[Prometeo]

That depends on what you value.

The mini split I have is more efficient than the (2013 or so) central HVAC system I had before. Lower losses because no leaking air too .

But the coil assembly visible in the rooms. But no big (metal duct) rumbling air flow.

I am not aware of people having mini splits in bathrooms. We did have a ducted HVAC register in the bathrooms back in TN.
Just an exhaust fan and window is used now for moisture control.

Thanks,
it's a 1500 ft apartment, with new floors, without heating systems built, because I had focused on heat pumps. I wonder if a 24000 btu split installed in the living room would also be able to transfer heat into bedrooms and bathrooms, considering the strong air movement, Or is it a huge mistake to think this way. In that case I would only install 2 more minisplits in the kids' rooms, given that their doors are the only ones that are almost always closed...

 

[stoveliker]

I have one head in the basement, one in the living room (South side of 1200 sq ft floor, open kitchen, but bedrooms/office on the North end of the home), and one in each of the kids bedrooms upstairs.
The living room has an 18000 BTU unit. The bedrooms can get quite hot (summer, AC) though - regarding heating, I can't say how well this works, as we use the minisplit only for heating about 40-45 degrees, and at that temperature our bedroom is just fine (we like to sleep colder). Below that we use the basement stove, and its heat comes up much closer to the bedrooms.

So generally it does not spread that well, I think. If you want the bedrooms the same temp as the living room, I'd install units there too. If you like it colder, it COULD work. In the bathroom I'd put in either electric floor heat or an infrared panel or so. Easier and quicker to heat, and comfortable.
Regarding the sizing, if it doesn't work moving the heat, you're likely sized too big - I have an 18000 BTU unit in a similar size floor - and that is bad as you'll short cycle. Good minisplits can turn down a lot, meaning they work best (longevity and efficiency) if they run continuously on a lower power. Minisplits in any case are not ideal for quickly heating up a cold home.

But it all depends on heat loss and heat gain (sun/shade, window orientation etc). That should be assessed quantitatively, I'd say. I.e. ask for a calculation to be done.

 

[Prometeo]

I have one head in the basement, one in the living room (South side of 1200 sq ft floor, open kitchen, but bedrooms/office on the North end of the home), and one in each of the kids bedrooms upstairs.
The living room has an 18000 BTU unit. The bedrooms can get quite hot (summer, AC) though - regarding heating, I can't say how well this works, as we use the minisplit only for heating about 40-45 degrees, and at that temperature our bedroom is just fine (we like to sleep colder). Below that we use the basement stove, and its heat comes up much closer to the bedrooms.

So generally it does not spread that well, I think. If you want the bedrooms the same temp as the living room, I'd install units there too. If you like it colder, it COULD work. In the bathroom I'd put in either electric floor heat or an infrared panel or so. Easier and quicker to heat, and comfortable.
Regarding the sizing, if it doesn't work moving the heat, you're likely sized too big - I have an 18000 BTU unit in a similar size floor - and that is bad as you'll short cycle. Good minisplits can turn down a lot, meaning they work best (longevity and efficiency) if they run continuously on a lower power. Minisplits in any case are not ideal for quickly heating up a cold home.

But it all depends on heat loss and heat gain (sun/shade, window orientation etc). That should be assessed quantitatively, I'd say. I.e. ask for a calculation to be done.

Thank you, good points of view that I hadn't considered, large splits actually have lower efficiency, and yes an infrared in the bathrooms could be a nice solution, I have to try one, if it is discreet it could be an auxiliary help even in the bedrooms, to be explored further..

 

[EbS-P]

Personal opinion….. ducted HVAC in every room (when done well) leads to more even temperatures than mini split heads in just a few rooms.

There are many more opportunities to make mistakes designing and installing a ducted system. Mini splits are easier for most retrofits

I’d be fine without mini split head in bathrooms if I had another heat source.

really it’s the space and how much you are willing to spend that chooses

 

[Prometeo]

Personal opinion….. ducted HVAC in every room (when done well) leads to more even temperatures than mini split heads in just a few rooms.

There are many more opportunities to make mistakes designing and installing a ducted system. Mini splits are easier for most retrofits

I’d be fine without mini split head in bathrooms if I had another heat source.

really it’s the space and how much you are willing to spend that chooses

Thank you, hvac certainly has many advantages, I think the lower noise inside the rooms is one of the main ones. In my case, I have a 645 sq ft lounge/kitchen and already in this case I ask myself, I should create at least 2 entry points, or 3, at that point perhaps 1 split is better. And I have 3 bedrooms and 2 bathrooms. Bathrooms, for hygienic reasons, should not be ducted...! So the bedrooms remain to be evaluated

 

[stoveliker]

In my experience ducted HVAC is far, far noisier than a mini split.

 

[EbS-P]

this is true for single speed regular units. My top of the line 2009 Trane is very quiet. The compressor makes less noise than the condenser fan. And on fist stage the blower makes nearly no noise. It’s a package unit so all the equipment is outside right by my bedroom window. I can hear it. It’s not silent. Mini split run 100% is probably far quieter.

 

[stoveliker]

In my experience both the outside (as you note ) and the inside is far, far quieter with a mini split.
I only hear the inside if it's blowing at full speed. The ducted HVAC was always loud with its air flow.

 

[Prometeo]

Thank you, ok so better not to fossilize on "noises" both potentially can do it, based on models / ways of use, and available speeds. To help me decide, a length of 25 feet of copper pipes for R32 gas as regards the canalized, it can reduce the yield, as I suppose, or it can be considered as a small thermal flywheel, therefore positive. While splits would have very short pipes up to the outdoor unit.

 

[Tonty]

We installed two mini split systems in my brother’s house. (He is out of the country on a mission term, and we are running his house as an Airbnb while he is gone. Previously had only wood stove heat and window a/c.) We installed two outside units, a 27,000 btu feeding three 9k air handler units in bedrooms, and a 36,000 btu feeding a 24k air handler in the main living area, and also a 12k air handler in a bigger bedroom. This is in an old (1900 or so) two story farmhouse, that has been mostly renovated in the last 30 years or so. But would by no means be as tight as a newer house. These are the Mr Cool DIY models, and we did all the work ourselves.
It’s hard to compare between mini splits and ducted units. I have a ducted unit in my house, and they both have pros and cons. I think mini splits have the potential to be more efficient because there is no duct loss. Mini splits are very quiet, as the fan usually runs on low speed if you have it set to auto. With a ducted unit, you don’t have to look at the heads on the wall or in the ceiling. In the case of this house, mini splits were considerable cheaper. We had a quote done for ducted hvac, and it was over twice the price since new ducts would have had to be run on both the main floor and the second floor. There are things about the mini splits I don’t like, and there are things about my ducted system I don’t like. So basically comes down to personal preference, or in our case, budget. For heat, we would have been better off with a ducted unit as far as being able to heat the house well. For a/c, the mini split way was a better choice in our scenario. I have no idea as far as from an efficiency standpoint which one would have been better. I know the mini split way didn’t drastically change the electric bill. These have no heat strip backup.

 

[Tonty]

Some of our units actually have quite long line sets. Close to the limit, I think one was close to 70’, but I’d have to double check that.

 

[Prometeo]

We installed two mini split systems in my brother’s house. (He is out of the country on a mission term, and we are running his house as an Airbnb while he is gone. Previously had only wood stove heat and window a/c.) We installed two outside units, a 27,000 btu feeding three 9k air handler units in bedrooms, and a 36,000 btu feeding a 24k air handler in the main living area, and also a 12k air handler in a bigger bedroom. This is in an old (1900 or so) two story farmhouse, that has been mostly renovated in the last 30 years or so. But would by no means be as tight as a newer house. These are the Mr Cool DIY models, and we did all the work ourselves.
It’s hard to compare between mini splits and ducted units. I have a ducted unit in my house, and they both have pros and cons. I think mini splits have the potential to be more efficient because there is no duct loss. Mini splits are very quiet, as the fan usually runs on low speed if you have it set to auto. With a ducted unit, you don’t have to look at the heads on the wall or in the ceiling. In the case of this house, mini splits were considerable cheaper. We had a quote done for ducted hvac, and it was over twice the price since new ducts would have had to be run on both the main floor and the second floor. There are things about the mini splits I don’t like, and there are things about my ducted system I don’t like. So basically comes down to personal preference, or in our case, budget. For heat, we would have been better off with a ducted unit as far as being able to heat the house well. For a/c, the mini split way was a better choice in our scenario. I have no idea as far as from an efficiency standpoint which one would have been better. I know the mini split way didn’t drastically change the electric bill. These have no heat strip backup.

Thank you, the powers indicated, they are all very tall, I imagine that the system can easily raise and lower temperatures. I believed that to install these devices, a vacuum tool was needed, good input, I'll check if I can do it too. It's also interesting about airbnb 😉

 

[Tonty]

The Mr Cool DIY line has pre-charged line sets and compressor. No vacuum pump or charging is needed.