Mini Split Running Costs

[hbabler]

How much have y'all seen your bills go up with the addition of a mini split for your garage? I know that there are geographical differences and differences in insulation but I am trying to get a rough idea before I proceed with this. Thanks
Hudson

 

[pseudorealityx]

How much does YOUR electricity cost?

 

[LS6 Tommy]

Don't have a mini split in the garage, but I have an 18k Btu in the basement and another identical one for the first floor. Energy usage has been less with both running (the basement unit has been running on "dry" almost all summer) than when all I had was a 12k Btu window unit for the first floor.

Tommy

 

[hbabler]

I pay 9-10 cents a kWh

 

[CWO4GUNNER]

All the factory, customer, and independent reviews I have read talk about the huge advantage to having the evaporator in the conditioned space as well as the saving of ductless systems over losses of up to 30% cooling and heating inharent in traditional evaporator and ducted systems operating in and through unconditioned spaces. Meaning that from the get-go there is a large advantage here.

That what they say anyway...

 

[Rickcnc]

I pay 9-10 cents a kWh

20 cents a kWh here, with all the extra charges dialed in

 

[CWO4GUNNER]

The highest here in BHC AZ....12 cents KWH peek time and 9 cents KWH during low use hours. This doesn't include some customer usage, renewable energy, state and city taxes ever month totaling $35. a total of 1741 KWH used for $216 as I have allot of large aquariums running pumps about 1200 gallons. If it wasn't for my 5000 CFM swamp cooler cutting into my Goodman 9 seer running time on dry days, my bill would almost be $350.

No wonder why people are jumping on the mini-split rescue wagon.

 

[Jackfre]

I can't break it out completely. My heat is a combination of mini splits (two for heating and 3 for cooling) . As well, I run a Rinnai EX22 LP wall furnace. They are an ideal combination system in my experience. Here in the foothills over the last year, for the whole place , well, heat, lights, etc my highest bill has been $85. In the shoulder seasons it drops to $50. Also in the re-model I replaced my electric water heater with a Rinnai tankless, so that is saving in the neighborhood of $40-50 per month. It has been hot here this summer and I've run the bejeepers out of these things.

With the performance of the mini-splits you are tickling the efficiencies of geothermal systems for a fraction of the price.

 

[CWO4GUNNER]

My heat is a combination of mini splits (two for heating and 3 for cooling). It has been hot here this summer and I've run the bejeepers out of these things. With the performance of the mini-splits you are tickling the efficiencies of geothermal systems for a fraction of the price.

Man what am I waiting for, I cant afford not to install mini-splits. Im losing money hand over fist. I mean like even if I get the high end LG brand it will pay for itself almost the 1st year for my main home. The tenants will also appreciate it but it would be locked up emergency only. But the more I think about it since I already have 3 emergency window units to dispatch, I might just do my home in mini-split and only do the tenants once there is a major failure coil leak/compressor burn of the central AC. Then just use the window units while I install a mini split in that rental. Yeah thanks for that info

 

[pseudorealityx]

All the factory, customer, and independent reviews I have read talk about the huge advantage to having the evaporator in the conditioned space as well as the saving of ductless systems over losses of up to 30% cooling and heating inharent in traditional evaporator and ducted systems operating in and through unconditioned spaces. Meaning that from the get-go there is a large advantage here.

That what they say anyway...

That's marketing speak. Although it's more true in residential than my world of commercial/industrial/institutional.

 

[Jackfre]

Pseudo, in your experience, what percentage of residential duct work is properly sealed with materials that will last. I represented Kingco and Polymer Adhesives back in the 80-90's and while on commercial, if you did not pass the pressure test you didn't get paid. On residential, until the new codes have come in there was no residential testing. Hence the DOE says an average leakage between 18-42% or the referenced 30% median. My 25 seer unit with no duct losses looks pretty good. I think the "net to the space" argument is very strong. Even in Commercial the unitary guys are freakin' out in the big cities. Mitsu and Daikin are lighting it up in the high rises with the commercial products too.

Now all I have to do is get my cleaning regimen in place

 

[pseudorealityx]

I don't have enough experience to say. On the commercial side, I won't accept a T&B that shows more than 10% leak when measured airflow at the unit outlet, and then a sum of the measured airflow at the diffusers.

And obviously less on the more critical jobs.

Like anything else, a lot of it comes from the contractor who installed it. And when it was done. An A/C duct system that hasn't been touched since the 1970's (like my house!) is very likely very poorly insulated and leaky. New construction is likely a lot better.

 

[CWO4GUNNER]

An A/C duct system that hasn't been touched since the 1970's (like my house!) is very likely very poorly insulated and leaky. New construction is likely a lot better.

I don't know but weren't they using metal solid ducting in homes in the 70's, not flex duct back then. More likely deficient becasue original ducting was for heating and undersized. I know today even though Flex duct seems to hold up material wise, the original install is sometimes terrible with support straps failing after a few years, ties snapping falling off where the ducting is attached to the plenum and tape drying out along all the connections and plenum seams. I couldn't believe after I graduated HVAC and inspecting my then 9 year old home attic, how shabby things were. Tightening up everything helped but there is still allot of inharent and build in leakage into the hot attic.

 

[pseudorealityx]

All of that. Hard metal is still a problem if you've got a crappy contractor who doesn't tape and/or mastic everything, or doesn't bother with that hard-to-reach corner or whatever and just uses some sheetmetal screws.

I still see TERRIBLE installations in the commercial field. Most typically... restaurants. Was at one yesterday with a bunch of exterior ductwork insulated with the bubblewrap stuff and regular grey duct tape. Ugh...

 

[Fishplate]

An A/C duct system that hasn't been touched since the 1970's (like my house!) is very likely very poorly insulated and leaky. New construction is likely a lot better.

My house was built in 1977 with hard ducts and fibreglas insulation. 18 months ago, I had all the ductwork in the unconditioned spaces sealed and all the insulation replaced.

My electric bills have dropped about 10-15%. The job has already paid for itself.

 

[CWO4GUNNER]

I understand now why allot of young independent small contractors try to do things different out here. One young popular contractor I know always tries to convince new restaurants, churches, and warehouse businesses with enough high ceiling space to install uninsulated round metal ducting in the conditioned space. He includes a ceiling paint scheme that is flat black. Then the round non-insulated metal ducting so much easier to load plan, size, fit and install is then painted with the same flat black paint scheme as the ceiling and Im telling you if you didn't know the ducting was there you cant see it in the conditioned space when you look up all you see is the last 1/4 of the flat black ceiling, no duct-work. And if the duct-work leaks a little here and there, there is no loss. The air-handler itself behind an insulated wall concealed.