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OGDanDogg
Sep 16, 2002


I have a two story house and a single HVAC unit with the thermostat and air intake in the upstairs hallway. Our downstairs always lags the upstairs (downstairs is colder in winter, hotter in summer), and I was looking at multi-zone solutions. All ducting is in the attic, so if I wanted to, I could do a legit dual-zone retrofit with automated dampers (like this: http://www.homedepot.com/p/Suncourt-10-in-A, utomated-Damper-Normally-Closed-ZC110/203227241) and whatever controls I need and static pressure issues I induce. Or I could just take the easy way out and buy an ecobee3 which has external wireless sensors, but forces all air through the attic and incurs whatever losses that involves. Thoughts? Up front cost of dual-zone retrofit vs. long term cost of running fan to force air through hot/cold attic ducting?

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iForge
Oct 28, 2010

Apple's new "iBlacksmith Suite: Professional Edition" features the iForge, iAnvil, and the iHammer.

Tore down a compressor off a Vilter low temp chiller at a local ice arena. I'm guessing that it got a slug of liquid. All pistons, liners, and the crankshaft are a loss. It will get rebuilt next week when the parts come in, but I'm not sure if I will be there for it.




rdb
Jul 8, 2002
chicken mctesticles?

I am looking for suggestions before I call someone.

I have an ancient janitrol central AC. It's a 2 ton, model CK24B or something like that. It's old and way undersized for the house. It mostly cools the downstairs which is 1400sq ft but has a couple ineffective registers upstairs which is another 600sq feet. I had quotes for a geothermal unit or another air source to be put in last year and they sized them at 3 tons.

Anyways, it runs for 5 minutes and shuts off. I cleaned the coil, changed the filter, tried a different thermostat and verified the drain is clear. It had a new capacitor and hard start kit last year. The compressor and fans start normally, no dimming lights or tripping breakers so I don't think it's that. What else could it be? It's 95, humid and pissing me off. I know it needs to be replaced eventually but that's not going to happen right away.

I would love to just DIY replace it and the A-coil but I don't have the license to handle R22.

MRC48B
Apr 2, 2012



Which coil did you clean, the evaporator (inside), or condenser (outdoor)?

rdb
Jul 8, 2002
chicken mctesticles?

Outdoor, I can't clean the indoor one easily. Now that the sun is off of it and the temperature has dropped to 85 degrees it's running normally again.

MRC48B
Apr 2, 2012



You may be hitting the high pressure limit switch, which would cause it to shut off. Unfortunately, there's quite a few different things that can cause that. One is a dirty condenser, the other is no airflow across the a-coil, or TXV issues.

It's really difficult to internet diagnose, because it's very enviroment dependent.

rdb
Jul 8, 2002
chicken mctesticles?

It definitely acts like a limit switch. I have a laser thermometer, is there anything I can check with that to narrow it down? The big tube going into the outside unit is the suction line, correct?

MRC48B
Apr 2, 2012



That would help.

Temperature of the big tube, which is the suction line.

Temperature of the small tube, which is the liquid line,

Temperature of the air coming out of your supply ducts, you can just laser the duct. it will be close enough.

Temperature of the return ducts.

All of this will still only be guess work. Because what I really need is refrigerant pressures while this thing is acting up.

Also, you wouldn't be fortunate enough to have an inspection hatch on the A-coil?
Some goodmans do.

ExplodingSims
Aug 17, 2010

RAGDOLL
FLIPPIN IN A MOVIE
HOT DAMN
THINK I MADE A POOPIE




If you're that committed to doing it yourself, get a cheap set of gauges and do a pressure reading. It's the only way to say what's going on for sure, but it sounds a lot like it is short cycling on the low pressure control.
If it's firing up and cutting off, with everything running, it's some kind of pressure issues, but you'll need readings to get an answer.

rdb
Jul 8, 2002
chicken mctesticles?

Will do. Thanks for the advice, I slammed a cheapie window unit from Walmart in the bedroom for tonight. It may be a couple days before I get back to this but I will.

rdb
Jul 8, 2002
chicken mctesticles?

I ordered a set of "Mastercool" digital gauges model 99661 today. Shipping takes a week but the deal was too good to pass up. Compatibility with about everything, vacuum sensor and a clamp thermocouple.

rdb
Jul 8, 2002
chicken mctesticles?

Ok, so the gauges I ordered did not come through and I borrowed a set from work.



It's about 85 degrees out, 71 inside.

Unit was cutting in and out when I got home but stopped when temp dropped below 90. I noticed that if its above 90 and I run a window unit in the house it doesn't cut out.

Chillbro Baggins
Oct 8, 2004
Bad Angus! Bad!


ExplodingSims posted:

You know what's really fun? Working on stuff all day then coming home to find your own A/C not running.
The cause? Cap died.



For reference, caps are supposed to be flat on the top. Not bulging out.

Oh, more stories from my dad's A/C shop: take a starter cap, duct tape the bottom of it to a sheet of tinfoil, wrap the rest of the foil carefully over the top in the size/shape of a soccer ball.So you've got a bigass cap at the bottom of a ball of tinfoil.

Throw it in the direction of the newbie and shout "think fast!"

When they catch it, it crushes the foil onto the contacts, makes a big bang, etc.. The foil will probably vaporize before they get lethal amounts of current.

Also, crosspost from the GBS OSHA thread:
The ceiling of the shop was rather low, and of course they built their own ceiling fans by hanging the fans from scrapped condenser units from the ceiling (if the fan craps out, you replace it, if the compressor craps out, it's often more economical to replace the whole unit with a more efficient one). Dad is not tall, and he once walked into one. Cut a good half-inch into the bill of his baseball cap. If Dad hadn't habitually worn a ballcap (he was bald even then, and wore it to protect against scalp sunburn), he probably would have at best needed stitches and at worst got an accidental lobotomy -- they also did commercial work, so some of their ceiling fans had some serious horsepower behind them.


MRC48B posted:

Advantages of HVAC: You can get in snowball fights in June.



Not shown: the two inches of snow on the evaporator. Didn't think to get a picture before I defrosted it.

My house's evaporator froze up about a month ago, took me way longer than I should have to troubleshoot it. Weakass breeze from the registers, running constantly when it's 89F out and 91F inside all day ... I literally grew up in an HVAC shop, I should've known. . Eventually I figured out how to pull the front panel off the air handler and "Oh. There's the problem, innit?" I put a shop light up pointing at it to help the thawing (alas I didn't have any fuckin' incandescent bulbs in the house, but CFLs throw off SOME heat), and the problem was eventually resolved. (Edit: I had a half-inch of snow on top of an inch of so)lid ice.)

It's okay if it freezes up once right? It's only a problem if it does it a lot?

Chillbro Baggins fucked around with this message at 02:10 on Jun 28, 2016

ExplodingSims
Aug 17, 2010

RAGDOLL
FLIPPIN IN A MOVIE
HOT DAMN
THINK I MADE A POOPIE




rdb posted:

Ok, so the gauges I ordered did not come through and I borrowed a set from work.



It's about 85 degrees out, 71 inside.

Unit was cutting in and out when I got home but stopped when temp dropped below 90. I noticed that if its above 90 and I run a window unit in the house it doesn't cut out.

Are you sure you have R22? That suction pressure seems fine for 22, but the head pressure is way too low for it to be 90* outside.
Did it stay that consistent the whole time?

Delivery McGee posted:

It's okay if it freezes up once right? It's only a problem if it does it a lot?

If it froze up once and only once it may have just been stuck running for way too long. Or you had a plugged filter or something.
But yeah, if it keeps happening something's wrong. Also, pro-tip for next time, just turn the blower on and let it run. That'll defrost it waaaaaay faster than a lightbulb ever will.

rdb
Jul 8, 2002
chicken mctesticles?

The unit is labeled for R22. I haven't tampered with it since buying house in 2014. I did have the propane furnace replaced in January of 2015 but they did not touch the refrigerant. The readings remained constant for the 20 minutes I had the gauges hooked up. It was about 80-85 degrees out the entire time, the 90 was before I had a chance to go outside and hook up the gauges.

When I purged the lines it did not smell of propane. I think it's still R22.

I think I may have a weak compressor. Last summer it wasn't starting. It would crank 2-3 times and then stop. I could see the condensing unit shake when it tried to crank. I did not have a meter at home capable of reading capacitance so I threw a new cap and a 2 wire(Supco spp6e) hard start at it to see if it would go again, and it did. However, it's never held the temp set point and does not dehumidify very well according to nest thermostat.

rdb
Jul 8, 2002
chicken mctesticles?

Well I think I figured some of my issues out.

The house is ca. 1900, so not designed for any sort of central heating/air.

It's a typical hack job install, flex duct everywhere, goodman, leaks, and the previous owner improperly installed an outdoor wood burning furnace coil on the return side. This only makes the single 10" return even more inadequate. There is no way it's getting the proper amount of airflow. So someone added a return "register" in the basement, and it was open, which explains the humidity problem. The filter box is also inadequate and doesn't fit any commercially available filters.

On the supply side, well, there are only a total of 10 registers. Only 8 work because the previous owner tied off the section of flex duct that goes upstairs and it collapsed and flows basically nothing. Add to that the fact there is no return upstairs and it's no wonder why it's always sweltering in the summer and freezing in the winter. Also, the pressure from tying it off has caused it to become disconnected from the trunk in crawl space. So yeah, leakage and all that.

So I closed the basement return, and found that my digital caliper box was the correct size to plug most of the return leak around the filter. Immediately more cool air was coming out on the first floor. I let it run like that all night and no freeze up or cutout.

I ordered a differential pressure manometer off amazon and I need to figure out exactly how much air this is flowing. I also need to open the metal around the A coil and get a model number and figure out what type of metering device is in use. Like everything else I touch it's a mess.

Picture of the monstrosity. I had the furnace replaced in 2015. The new one has an ECM blower which compensates for some of my problems but not all. The makeup air connection needs to be installed as well.

MRC48B
Apr 2, 2012





Yeah. You found your issue. You need to do some sheet metal work there.

ExplodingSims
Aug 17, 2010

RAGDOLL
FLIPPIN IN A MOVIE
HOT DAMN
THINK I MADE A POOPIE




You know, you probably could have just posted that pic and saved yourself a lot of time here.


The hackiest of hack work.

MRC48B
Apr 2, 2012





Dont use wirenuts kids

Aquila
Jan 24, 2003



So I am looking into buying an AC unit for my Grandma and am trying to figure out roughly how much this will cost before I bring out someone for an estimate. She lives in Socal and removed the unit the house had when she moved in 25 years ago, according to her the coil is still there and drained of the refrigerant. I suspect after 25 years that stuff will not be reusable, but hopefully the install won't be to hard since the infrastructure is still there. The house is 1750sqft 3bdrm two story. I am hoping to spend less than $4000 (probably split with other family members) and am wondering if any knows roughly how much this stuff costs. Also I am considering using the Costco/Lennox deal, with various promos it will be zero interest and ~14% cash back.

kid sinister
Nov 16, 2002


Aquila posted:

So I am looking into buying an AC unit for my Grandma and am trying to figure out roughly how much this will cost before I bring out someone for an estimate. She lives in Socal and removed the unit the house had when she moved in 25 years ago, according to her the coil is still there and drained of the refrigerant. I suspect after 25 years that stuff will not be reusable, but hopefully the install won't be to hard since the infrastructure is still there. The house is 1750sqft 3bdrm two story. I am hoping to spend less than $4000 (probably split with other family members) and am wondering if any knows roughly how much this stuff costs. Also I am considering using the Costco/Lennox deal, with various promos it will be zero interest and ~14% cash back.

She's in California. Have you checked if there are any rebates or tax credits for energy efficient models? I got a feeling if any state had that stuff, it'd be CA.

angryrobots
Mar 31, 2005



Oven Wrangler

Nitrox posted:

Sup, thread



From the OSHA thread, if anyone doesn't follow it.

Qwijib0
Apr 10, 2007

Who needs on-field skills when you can dance like this?


Fun Shoe

Aquila posted:

So I am looking into buying an AC unit for my Grandma and am trying to figure out roughly how much this will cost before I bring out someone for an estimate. She lives in Socal and removed the unit the house had when she moved in 25 years ago, according to her the coil is still there and drained of the refrigerant. I suspect after 25 years that stuff will not be reusable, but hopefully the install won't be to hard since the infrastructure is still there. The house is 1750sqft 3bdrm two story. I am hoping to spend less than $4000 (probably split with other family members) and am wondering if any knows roughly how much this stuff costs. Also I am considering using the Costco/Lennox deal, with various promos it will be zero interest and ~14% cash back.

Different markets and all that, but when I was looking, the Costco Lennox bid was more expensive than using the local Lennox sub they contract with directly, and both those numbers were almost 30-40% more than bids from highly reviewed carrier/bryant and ruud/rheem dealers.

chedemefedeme
May 25, 2007

Until then I need your help
figuring out the logistics!

Just moved my company into a new office/warehouse thing. Has what looks to be a heat pump to my amateur eyes. Simple condenser unit on the roof and handler inside above the office. Only 900sqft of space to condition.

The space came with a super basic non programmable thermostat. Set it to a temp and it leaves it there 24/7. With this thermo the unit would come on and off as expected and keep the temp around 76, our setpoint.

After seeing my first electric bill with the unit just left at 76 all the time I installed a programmable thermostat set for business hours. Since then the following has been observed:
- The unit manages to maintain my "away" temp of 85 running ~20 minutes an hour. Seems a bit much but ok...
- Despite a setpoint of 76 the unit brings the temp in the office down from 85 to 79 during business hours.
- The unit never reaches 76 and ran for 9 hours straight attempting to do so until the biz day was over and it set back to the away temp of 85.
- It then maintained 85 just fine running ~20 minutes an hour the whole night with no more than a 1 degree variance from 85.

What the gently caress?

What the hell could I have f'd up simply changing a thermostat that would have the thing cool but not cool efficiently? Wouldn't it just be i hooked up the wire right and it cools or I didn't and it blows but doesn't cool? How the crap did I end up with it "kindof" cooling?

I'd call an HVAC guy out to look at the system except this is 100% correlated with my change of thermostat. On the old one it always reached the set point within reasonable time and would then get to turn on and off only as needed. I'd say maybe the sensor in the thermostat is bad but if that were the case we'd be freezing our butts off. Instead it genuinely was indeed ~79 degrees in the office. We're in texas so we'd know darn quick if it wasn't cooling at all but on the other hand if it was working normally after 9 hours of continuous cooling we'd all be frozen solid.


Edit: Fun fact, the AC unit was inspected less than a month ago upon move in and passed, so it's not like it's been on the roof for 20 years without service.

chedemefedeme fucked around with this message at 19:16 on Jul 17, 2016

STR
May 12, 2006

I thought I was a nice jester


How long did it run during the day when set at 76?

It's possible it just doesn't have enough oomph to bring the place back down to 76 when the sun is out. I know the ac at my parents house is like this - it's fine if you leave it alone, but if you shut it off for awhile, it won't get back down to its set point again until after the sun has gone down. With it running 20 minutes an hour while at 85, I'd guess this is pretty likely; theirs runs nonstop from about noon until 9pm.

Make sure you didn't connect Rh or W to Rc or Y; doing that would be calling for both heating and cooling. You may try having it kick on a bit earlier in the day too, to give it a head start.

chedemefedeme
May 25, 2007

Until then I need your help
figuring out the logistics!

some texas redneck posted:

Make sure you didn't connect Rh or W to Rc or Y; doing that would be calling for both heating and cooling.

Can a heat pump even run heat and cool at once? It would make a lot of sense if they were fighting each other except that I didn't think heat pumps worked that way.

I did test putting it into heat mode after install and it blew warm air. It also blew cool air in cool mode..or so I thought. Apparently not cool enough...

minivanmegafun
Jul 27, 2004



So I bought an old, c 1885, 2-story workers cottage in Chicago. It has a pair of gas-fired wall furnaces (one on each floor), and the idea is to modernize the HVAC. The wall furnaces are reasonably efficient (lack of insulation notwithstanding).

For those of you not familiar with the standard Chicago workers cottage, they're about as simple as layouts get. The building is rectangular, the roof is pitched facing the street, and the construction is standard balloon frame. In our case the layout of the two floors is pretty close to identical (it's split into two apartments) but we'll be tearing walls down and rearranging things. Our house is pretty small, roughly 600 sq ft per floor.

I keep looking at Mitsubishi Mr SLIM units - are those at all a viable option for both heating and cooling in my climate? Are they strictly electric-only, or can they run on gas?

If we go for a traditional split system, is running the ductwork between the floors, making it on the ceiling on the lower level and in the floor on the upper, a viable option?

It's also worth mentioning that we're planning on putting the sleeping quarters on the lower level, this home was built pre-street-raising-for-sewers, so it's essentially a house in a four foot deep hole, from the perspective of the sidewalk.

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

chedemefedeme posted:

Can a heat pump even run heat and cool at once? It would make a lot of sense if they were fighting each other except that I didn't think heat pumps worked that way.

Only if it's a gas unit. Actually, I take that back......I suppose on a pure heat pump that on some units you could have the electric resistance coils (emergency heat) running along with AC.

chedemefedeme posted:

I did test putting it into heat mode after install and it blew warm air. It also blew cool air in cool mode..or so I thought. Apparently not cool enough...

How warm was the warm air? Heat pump "warm" isn't usually very warm. If it was, you may have some other heat source on.

angryrobots
Mar 31, 2005



Oven Wrangler

Motronic posted:

Only if it's a gas unit. Actually, I take that back......I suppose on a pure heat pump that on some units you could have the electric resistance coils (emergency heat) running along with AC.
This is the case in most of the southeast. You only rarely find gas heat in residential or small commercial (although it is becoming common in new mid to high level subdivisions being built, which is silly IMO because an efficient new home would best take advantage of our cheap electricity with all electric appliances but I digress).

Anyhow my point is that the unit does probably has electric 2nd stage heat and it is possible to run both at the same time. But I doubt you would cool off at all in mid- summer like this, if that were the case?

My suspicion is that the building is poorly insulated, possibly a metal strip mall style structure in full sun with a bank of windows up front, and the change to an 85°F unoccupied setting happened at the same time that the outside temp is getting higher and holding until later at night.

I would recommend holding at 76° like you had it for one day, see how it performs, and if it holds, then bump the unoccupied temp up by 1° every day until you find out what it can recover from.

chedemefedeme
May 25, 2007

Until then I need your help
figuring out the logistics!

Motronic posted:

Only if it's a gas unit. Actually, I take that back......I suppose on a pure heat pump that on some units you could have the electric resistance coils (emergency heat) running along with AC.


How warm was the warm air? Heat pump "warm" isn't usually very warm. If it was, you may have some other heat source on.

The unit would not run for 9 hours before the new thermo to hit the temp. It would run, say, 40 to 60% of any given hour during the hottest parts of the day..about normal for a unit that looks to be maybe 5 to 10 years old.

When the heat was on it was lukewarm heat pump heat. I have one at my house and am familiar with how they work. Our mild winter (snows for real maybe once a decade..and melts the next day) in Austin, Texas means we have heat pumps installed left and right. My home system does have emergency heat coils. Unsure if the office install does or not. There were very few wires to hook up - less than at my house, if I recall correctly.

No gas in this office .All electric appliances and hvac.


I definitely did it with my thermostat install I just can't figure out how!


angryrobots posted:

My suspicion is that the building is poorly insulated, possibly a metal strip mall style structure in full sun with a bank of windows up front, and the change to an 85°F unoccupied setting happened at the same time that the outside temp is getting higher and holding until later at night.

I would recommend holding at 76° like you had it for one day, see how it performs, and if it holds, then bump the unoccupied temp up by 1° every day until you find out what it can recover from.

It's a tilt-wall style warehouse with insulated structure built inside of it. The high warehouse ceilings (~24ft) are also insulated. In the warehouse it gets up to maybe 95 on the hottest of days since we are on the east side of the building and not getting the worst of the sun. This is an easier job than the vast majority of AC units here in Texas have. It worked reasonably before I came and (apparently incompetently) installed the new thermostat.

Lemme see if I was smart enough to take a photo of the old wiring before i screwed it up.

chedemefedeme fucked around with this message at 23:50 on Jul 17, 2016

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

Other possibility: you sure it's not a multistage unit that you didn't set up right?

You did take a picture of the t-stat wiring before, right?

Let's see it or at least the new wiring.

chedemefedeme
May 25, 2007

Until then I need your help
figuring out the logistics!

Motronic posted:

Other possibility: you sure it's not a multistage unit that you didn't set up right?

You did take a picture of the t-stat wiring before, right?

Let's see it or at least the new wiring.

I have no flippin idea if it's a multi stage. I don't even know what that means

Edit: I can tell you it's not part of something else in the building like a central chiller though. There's one small residential looking fan/coil unit on the roof and one air handler smaller than the one in my attic sitting on top of the office inside the warehouse. Between the two run the thin copper coolant lines you'd expect on a residential heat pump/ac. The unit is entirely standalone and serves only my office inside my segment of the warehouse.

Found my pre-install pic. This is the back plate of the old thermostat before I removed it. Tell ya much?

chedemefedeme fucked around with this message at 23:56 on Jul 17, 2016

Motronic
Nov 6, 2009


MOTRONIC FOR MODERATOR, MAKE AI GREAT AGAIN


Grimey Drawer

Yeah, it tells me you don't have multi-stage heating or cooling or emergency heat.

That's about as simple of a heat/cool setup as you can have.

I'm gonna refer you to the last 2 paragraphs of angryrobots post as the most likely issue at this point.

chedemefedeme
May 25, 2007

Until then I need your help
figuring out the logistics!

Thanks for looking at it. Good to know for sure I didn't make the wrong assumption about system type. I'd agree his explanation would seem likely except for the type of construction this is. It's an insulated warehouse with a freestanding, also insulated, office structure built inside of it. We're surrounded by other tenants on 3 sides and our one exterior wall faces east and so misses the heat of the day. The warehouse itself is often between 85 and 95. This AC has it easier than what most in texas have to deal with.

At this point might it be safe to assume the inspection done by the landlord's contractor that the landlord would have had to pay for repairs from before the system was turned over to my responsibility was bull crap and that I should have the system serviced by someone actually motivated to find problems with it?

literally a fish
Oct 2, 2014

German officer Johannes Bolter peeks out the hatch of his Tiger I heavy tank during a quiet moment before the Battle of Kursk - c:1943 (colorized)


Slippery Tilde

Yup. System might just be undersized, too.

chedemefedeme
May 25, 2007

Until then I need your help
figuring out the logistics!

So I don't get taken by whoever I call out to look at it what justifies undersized for an office of just 900sqft? I feel like I've had window units that could cool this much space faster than this.

How might I get away here without buying a whole new/larger system but also not running the current one so hard?
Anything I should be asking about?
Should know to watch out for (common scams/grey practices)?

Thanks for the advice so far.

angryrobots
Mar 31, 2005



Oven Wrangler

Could be something as simple as dirty coils. Is the condenser located on the roof of the warehouse, or above your office but inside the larger warehouse structure?

ExplodingSims
Aug 17, 2010

RAGDOLL
FLIPPIN IN A MOVIE
HOT DAMN
THINK I MADE A POOPIE




Yeah, it pretty much sounds like you took it from maintaining a constant temperature and now it actually have to work to pull the building temp back down.
Mind, you, that a perfect system, only gets a 20* split across the evap coil, so it's got to do a lot of work to cool the building down from 85*. Combine this with poor insulation, and it's gonna have a hard time.
The other thing to consider, is what's in the building? Is this a store where you have lots of computers or people going in and out? I mean, if you're sucking in hot air every time someone opens the door, then yeah, that's going to contrubute.

Whenever we program a building's A/C, we usually don't go higher than 80*. Of course, this is in Florida, where the humidity will gently caress stuff up something awful.
And to answer your question about what goes into determining unit size, a lot. Square footage is one thing, but then you also have to factor in room contents, windows, insulation, doors, etc.

This is a simplified version of what kind of heat load calculations go into designing a system:
http://www.loadcalc.net/

minivanmegafun posted:

So I bought an old, c 1885, 2-story workers cottage in Chicago. It has a pair of gas-fired wall furnaces (one on each floor), and the idea is to modernize the HVAC. The wall furnaces are reasonably efficient (lack of insulation notwithstanding).

For those of you not familiar with the standard Chicago workers cottage, they're about as simple as layouts get. The building is rectangular, the roof is pitched facing the street, and the construction is standard balloon frame. In our case the layout of the two floors is pretty close to identical (it's split into two apartments) but we'll be tearing walls down and rearranging things. Our house is pretty small, roughly 600 sq ft per floor.

I keep looking at Mitsubishi Mr SLIM units - are those at all a viable option for both heating and cooling in my climate? Are they strictly electric-only, or can they run on gas?

If we go for a traditional split system, is running the ductwork between the floors, making it on the ceiling on the lower level and in the floor on the upper, a viable option?

It's also worth mentioning that we're planning on putting the sleeping quarters on the lower level, this home was built pre-street-raising-for-sewers, so it's essentially a house in a four foot deep hole, from the perspective of the sidewalk.

Mr. Slim units are pretty nice, especially since you can run multiple evaps off of one unit. And they're heat pumps only. No room for gas in those things.

And, I've never really heard of running one duct with one side on the floor and the other on the ceiling. I'm sure it's theoretically possible, but It seems like you'd have a hard time pressurizing it properly to get good airflow.
I'm not 100% sure though, our company doesn't to ductwork. Thank God.

ExplodingSims fucked around with this message at 01:39 on Jul 18, 2016

chedemefedeme
May 25, 2007

Until then I need your help
figuring out the logistics!

ExplodingSims posted:

The other thing to consider, is what's in the building? Is this a store where you have lots of computers or people going in and out? I mean, if you're sucking in hot air every time someone opens the door, then yeah, that's going to contrubute.

It's a private office with only 3 desks, one door to the outside world, and no windows. It's literally a 900sqft wood and sheetrock (w/ fiberglass insulation) office built inside of a 24ft high warehouse space, the remaining 2000sqft of which is the high ceiling warehouse. The "outside" unit is on the true roof, not inside the warehouse.


ExplodingSims posted:

Whenever we program a building's A/C, we usually don't go higher than 80*. Of course, this is in Florida, where the humidity will gently caress stuff up something awful.
And to answer your question about what goes into determining unit size, a lot. Square footage is one thing, but then you also have to factor in room contents, windows, insulation, doors, etc.

This is a simplified version of what kind of heat load calculations go into designing a system:
http://www.loadcalc.net/

I went for 85 since that's what I do at my house. My house can recover from this lickedy split. The home probably half as old as this warehouse although the AC unit appears to be about the same age. It is cooler in the warehouse than it is outside my house at virtually all times. The warehouse containing our office structure, facing east and surrounded by neighboring units on 3 sides, never gets as hot as the outside air temp.


Humor me this, though. Last night it got down to maybe 70 outside. My wifi thermostat's stats show it ran 30 to 40 minutes of every hour to maintain 85 degrees...is that still normal?

I'm fine setting the "away" temp to 80 instead of 85 but I want to be sure I'm not wasting money if something else is wrong. Should it require more than 50% runtime to maintain 85 degrees in a 900sqft space with 3 desks in in the dead of night? There was literally not an hour the past two nights it didn't run at least 30 minutes all night long.

chedemefedeme fucked around with this message at 02:34 on Jul 18, 2016

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JimbobDobalina
Aug 29, 2005

I will munch on your endocrine system


The arsehole previous owner of my house had an ac installed some years ago, and left the drain pipe coming out underneath the floor of an outbuilding, consequently rotting out the floor structure from having untreated wood sitting in standing water. I've torn down the lovely outbuilding, and am planning on building a concrete patio area in its place. Right now, the drain is dripping onto the dirt where the building was, and there is enough water coming out to leave a 2 sq ft puddle by the end of the day. I don't really want this much water dripping onto the concrete I plan to lay, but my yard is also sloped such that the outlet would be below ground level if I was to extend it out beyond the pad.
Any ideas for a better drain?
I don't really want to relocate it completely because the side of my house where it is now will be pretty well all patio, and the other side is a no go because of the grade.

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