so cal/ don't like ducts 1

[hanque]

Hi Everyone,

I'm an architect working on a 3-level SFD in los angeles, apx 2400 sf.
As an alternate to forced air I'm considering combining hydronic radiators or baseboards (not radiant) w/ ductless mini splits.

I'm also looking for someone to help to design the system.
Thank you!

 

[317069]

What is SFD

 

[hanque]

Single Family Dwelling
Thanks!

 

[tys90]

What about a multi-split system (all mini splits connected to one condenser) with a heat pump that operates at low ambient temperatures? LG makes a residential style capable of heating down to 6^oF so you wouldn't need any type of auxiliary heating.

 

[hanque]

That is a good idea for the sleeping rooms, which are small. The middle level (living/dining/kitchen) is about 1100 sq ft all open with some ceiling heights of 10' so I'm a little worried about stratification. I also just prefer the radiant heat. I think radiant is not common here (southern California) because most systems are designed for cooling, but I'm wondering if there's another reason like radiant systems in warm dry climates like ours don't make sense?
Thank you!

 

[sprinkler1000]

Go with VRF systems. Daikin, Mitsubishi,Toshiba are manufacturers among others.

Multisplit may be small for that área (if it is 2400 sq ft each dwelling).

Mixing radiant heating with air conditioning is the best you can install, but with the air conditioning heat pump in that climate should be more than enough, and saving the radiant heating cost.

 

[EnergyProfessional]

Here in WI I definitely would say use the radiant in addition to whatever you cool with. But we have -15°F design temp...

What is your design temp? So-Cal sounds to me like VRF would be good enough. Mitsubishi has some hyper-heating versions of theirs for colder climates. But again, so-Cal sounds to me heating is not an issue unless I'm mistaken.

 

[hanque]

Thank you for your input.
I should have posted these earlier, but here is a link to some drawings & renderings.
Thank you!

 

[oofowf]

With Title-24 changing in June 2014 you are wise to consider ductless systems in California.

A VRF heat pump system would offer both heating and cooling with only one set of refrigerant lines. install labor can be reduced a lot by using the heat pump instead of the hydronics for heating, especially if you are going to install the refrigerant lines anyways.

I don't see hydronic heat too often in SoCal except for older buildings circa 1920s with those nice old iron radiators.

If you are set on hydronic heating, then also consider a hydronic heating & cooling system. A contractor friend here in Northern California installs an air-to-water heat pump that provides space heating, space cooling, and domestic hot water. I've done a study on one of his homes that puts it near net zero energy with a small PV system, pretty neat.

 

[hanque]

oofowf,
that does sound neat!
I thought that hydronic cooling would not be an option in my case because it's a wood framed building and condensation would invite moisture where it's not welcome, but maybe I'm wrong?

HerrKaLeun,
I'm not sure what the design temp but this chart shows Summer/Winter averages in Los Angeles.
My heart goes out to you in -15° WI


Thanks again!

 

[hanque]

oh wait it is on that chart...design temp is 35...same as Miami!

 

[willard3]

Read forum policies which begin as follows:

These fora should not be used to bypass your own in-depth research on the issues that affect you, nor is it intended to be a substitute for appropriate professional assistance within your field or geographical region.


Hire an Engineer and don't try to cheap out and get free Engineering advice here.

 

[EnergyProfessional]

hanque: this may sound radical, but if you insulate right you almost need no heating at all at 35°F. a VRF system will be more than enough for heating.
I have a good house, (not really great) and don't need to turn on heat before ~50°F, and that only because of the wife. I bet if you insulate better, have better windows and include a sweater you could get rid of heating at all.
Maybe I spent too much time int eh cold, but here in WI you see people in shorts whenever it is above 0°F

 

[hanque]

Thank you all for the input.