Homeowner/HVAC crew question.

[[DWI]]

We are looking at adding Mini-split units in our house to retrofit cooling and handle shoulder season heating.

We've down to two very similar proposals that seem to make sense. The only real difference between the two is the one uses a multi-zone outdoor unit, while the other uses 1-to-1 indoor and outdoor units.

Each point to their own pros, 1-to-1 seems to have better efficiency numbers and redundancy, while multi-zone has lower upfront/install costs and less moving parts/points of failure. The cons are basically the opposite of the other's pros.

So what do the guru's of OT say?

 

[Bloke]

I thought the point was they are dyi? Why would you need quotes just order some and install them?

 

[nosaj]

Definitely not a DIY, My dad installs Fujitsu I have never helped on an install so have a bump.

 

[Leonard Washington]

I thought the point was they are dyi? Why would you need quotes just order some and install them?

Not a DYI by a long stretch. Gotta be wired into the panel, drill a hole in your wall and shit. It was the only upgrade I’ve done to my house that I had to get a professional in for. Plus the warranty was void if it wasn’t installed by the company and wired by a red seal electrician

 

[Leonard Washington]

Definitely not a DIY, My dad installs Fujitsu I have never helped on an install so have a bump.

those dudes make it look easy, I got an 18k btu unit installed and it was functional in 4 hours. Dudes were legit, they definitely had a knack

 

[whatever]

id personally go multi head vs a 1:1 setup. unless its just 2 units at opposite ends of the house.


i would consider going 2 multi head units for redundancy sake. if one breaks the whole house isnt fucked.

 

[whatever]

I thought the point was they are dyi? Why would you need quotes just order some and install them?

some are. mr cool is the name brand.

the good units are not. you gotta flare and pull a vacuum. other wise its pretty easy.

 

[93rx7]

some are. mr cool is the name brand.

the good units are not. you gotta flare and pull a vacuum. other wise its pretty easy.

ive had the flare tool and vacuum pump in my amazon cart for years

i scrapped the heated floor idea and am going with a 4 zone mini split. will be installing it so it should be entertaining.

 

[93rx7]

those dudes make it look easy, I got an 18k btu unit installed and it was functional in 4 hours. Dudes were legit, they definitely had a knack

if youre putting in multiple units youll be a pro by the time you get to the last one

protip: put the first one in the room you care about the least tbh

 

[whatever]

ive had the flare tool and vacuum pump in my amazon cart for years

i scrapped the heated floor idea and am going with a 4 zone mini split. will be installing it so it should be entertaining.

i would never give up my heated floor in the bathroom.


if i build a house it will have a poured concrete floor with heat in it. its way way too good IMO.

 

[nosaj]

i would never give up my heated floor in the bathroom.


if i build a house it will have a poured concrete floor with heat in it. its way way too good IMO.

Rich friend heated his man cave/garage floor.

 

[whatever]

Rich friend heated his man cave/garage floor.

i plan to heat my sidewalks and driveway. miles of pex pipe

 

[[DWI]]

id personally go multi head vs a 1:1 setup. unless its just 2 units at opposite ends of the house.


i would consider going 2 multi head units for redundancy sake. if one breaks the whole house isnt fucked.

A full house retrofit, due mostly to layout and closed doors, would be either 5 or 6 heads; 3 bedrooms and a common area on each floor. One of the common areas could be handled by one large unit or two smaller units, hence the 5 or 6 heads. We still deciding whether to do the whole house or a more limited approach.

There is a possibility on the full retrofit to do 2 multi-head units and on the 6 zone route it is pretty much a sure thing.

Is there a specific reason you would go for the multi over the 1-to-1?

 

[nosaj]

i plan to heat my sidewalks and driveway. miles of pex pipe

I have seen it done But if something goes wrong 11tybillion dollars shot to hell.

 

[Leonard Washington]

i plan to heat my sidewalks and driveway. miles of pex pipe

I used to work with a fat rich dude who heated his driveway so we all made fun of how lazy he was, but it was the Most baller shit of all time and I believe it was a solar water heater as well so operation was basically free

 

[nosaj]

A full house retrofit, due mostly to layout and closed doors, would be either 5 or 6 heads; 3 bedrooms and a common area on each floor. One of the common areas could be handled by one large unit or two smaller units, hence the 5 or 6 heads. We still deciding whether to do the whole house or a more limited approach.

There is a possibility on the full retrofit to do 2 multi-head units and on the 6 zone route it is pretty much a sure thing.

Is there a specific reason you would go for the multi over the 1-to-1?

The more you explain the more I think you're filthy rich

 

[whatever]

A full house retrofit, due mostly to layout and closed doors, would be either 5 or 6 heads; 3 bedrooms and a common area on each floor. One of the common areas could be handled by one large unit or two smaller units, hence the 5 or 6 heads. We still deciding whether to do the whole house or a more limited approach.

There is a possibility on the full retrofit to do 2 multi-head units and on the 6 zone route it is pretty much a sure thing.

Is there a specific reason you would go for the multi over the 1-to-1?

1:1 will not be as energy efficient. running watts will be higher. more losses. but there are some factors with that.

also 6 outside units will be looking. like you got a hotel.

i would do sleeping areas and living areas. 1 unit for each. multiple heads. the end.

 

[nosaj]

I used to work with a fat rich dude who heated his driveway so we all made fun of how lazy he was, but it was the Most baller shit of all time and I believe it was a solar water heater as well so operation was basically free

Dude went to his condo in Miami in the winter. Friends mom took care of the house when he was gone.

 

[[DWI]]

I thought the point was they are dyi? Why would you need quotes just order some and install them?

There are some DIY with pre-charged lines, but they aren't as good and do not have any real local support for repairs, at least as far as I can tell.

As for DIY'ing the good stuff?

Legally: You need an EPA certification (608 Type II, I think) to let the refrigerant out.
Electrically: You'll be pulling a 240v circuit for each
Plumbing: You'll at least be cutting and flaring copper tubing
Meh-to-scary: you'll be punching holes in the exterior of your house
Math is hard yo: Heat load calcs look scary AF.
Support: DIY if without being licensed HVAC (or at least EPA certified) if not certified by the manufacturer and no warranty for you.

Overcome or ignore all of that and one could DIY it.

 

[Bloke]

ive had the flare tool and vacuum pump in my amazon cart for years

i scrapped the heated floor idea and am going with a 4 zone mini split. will be installing it so it should be entertaining.

Flaring sucks brazing is so much easier

 

[[DWI]]

1:1 will not be as energy efficient. running watts will be higher. more losses. but there are some factors with that.

also 6 outside units will be looking. like you got a hotel.

i would do sleeping areas and living areas. 1 unit for each. multiple heads. the end.

When I looked to backup the claim of more efficient, albeit briefly, the rated numbers seemed to back that claim. I will have to look closer at that.

As for 6 outdoor, yeah odd as heck, but I actually have a place I could place them under the deck and you'd never seem them.

Cooling load is about 4 tons and heating load is about 6 tons, of course when the full 6 tons is needed it is cold enough that ASHP's could be reduced output.

 

[whatever]

Flaring sucks brazing is so much easier

lol its super easy now.

 

[whatever]

When I looked to backup the claim of more efficient, albeit briefly, the rated numbers seemed to back that claim. I will have to look closer at that.

As for 6 outdoor, yeah odd as heck, but I actually have a place I could place them under the deck and you'd never seem them.

Cooling load is about 4 tons and heating load is about 6 tons, of course when the full 6 tons is needed it is cold enough that ASHP's could be reduced output.

under the deck? hope its a second floor deck and not a fuck the service guy deck.


6 heads. again i'd go bedrooms and common areas. 2 multi heads. redundancy. smaller size outside units. and not filling up your electrical panel with 12 breakers

 

[whatever]

think about service costs down the line for 6 units vs 2.

 

[[DWI]]

i plan to heat my sidewalks and driveway. miles of pex pipe

I got a co-worker, who is went halfway. He has a snow melt pad. Pushes all the snow there with his tractor (that he keeps in his heated garage) and flips the switch.

Giant ass ice sheet going down the hill next to the pad.