admiraldennis posted:

What do y'all think of SDHV/Unico?

I'd love to transition away from my aging fleet of window A/Cs in the upper unit of this 125 year old house.

There are existing large ducts for the forced air furnace which work great for distributing heat. The lower unit (first floor, plus a single room on the 2nd floor) has conventional central A/C through these existing ducts, and it works fine. I've been told it's not super viable to get cold air up to the 2nd and 3rd floors in the same way, due to the effort of trying to blow cold air up big ducts to a 3rd story. I tend to believe this as the single 2nd floor room on the downstairs unit struggles a bit to stay cool. The entire 3rd story gets HOT, too, especially my office which is at the center and filled with computers.

It seems like my options are:
1. Mini-Splits. I'd need at least 5x wall units to cover the three 3rd floor bedrooms and the downstairs living/dining + kitchen areas. I use 5x window A/Cs now.

2. SDHV? Blowers could potentially go in attic space above 3rd floor. I like how nice and neat and small they look compared to mini-splits. We had them in a house growing up and they seemed to keep everything very cool.

3. Conventional A/C through existing heat ducts? Maybe actually possible, despite what I've been told?

I wouldn't be DIYing this but I could use some steering as different contractors push different things.

Pollyanna posted:

Returning to the topic of my apartment’s hosed up central heating.

The forced air heating has no filter. When I asked why, the response was “because we’d have to install a slot for it and a way to change it”.

The motherfucker is still spewing crap everywhere.

It is by far the worst in the bathroom.



I can handle it in the kitchen, living room, and bedroom, cuz I can vacuum. But in the bathroom, because it’s a small room, it gets everywhere. On the floor, on the sink, on the toilet, in the bathtub. It’s awful and I’m sick of wiping off dust, dirt, wood chips, and bits of plastic every time I go take a piss.

I don’t care about heating the bathroom. I want to simply stop the forced air from entering the bathroom at all.

What would it take to add a total cover to the duct vent?



This is with the vent “cover” removed. The cover does not have a way to close it at all, so that’s not an option.





My idea is to just put a metal or even plastic “lid” on this to simply stop the air from flowing in at all. Something airtight so no air can get through. Plus, I can just remove that cover once I leave.

Is this doable?

And yes, I know I could just use a vent cover that does close. I’m trying that out first. This is just in case!

Pollyanna posted:

What kind of filter? You mean like one of those lovely fabric-looking ones, or an actual HEPA/one-way thing?


They call my city Slummerville for a reason. I’m moving in 2021 cuz lmao gently caress this.

Pollyanna posted:

You can cut those???? :o

KS posted:

Based on testing, I need to install some radon mitigation. I have a 2-story house. I'd really rather avoid the typical installation of white PVC pipe running up the outside of the house from the basement to the roofline, and there aren't a lot of spots to do it based on the nature of the house.

I have an ~18' vertical access path from the center of the basement to the attic, 2'x4' or so, that houses the HVAC supply and return ducts for the upstairs zone. That leaves about a 1x1 opening and I suggested we use that -- the mitigation company ran with it and I have a quote to install a system through that path and out through a roof penetration.

Am I shooting myself in the foot in any way here related to HVAC maintenance down the road? The vertical ducts are ductboard and I believe they're from the 80s. They connect to spiders in the attic that are in rough shape insulation-wise.

Ducts in basement. Conduit is loose, also considering running data through here. Stray wires are from an old security system I'm ripping out slowly.


Looking up access:

stratdax posted:

Just spitballing some options here, but if you're sticking with two systems anyway, just using ductless splits in the downstairs (and no forced air at all) might be a way to go.

You can also put the house on one big condensing unit and use a mix of ducted air handlers for the upstairs, and ductless splits downstairs. (Or just eliminate all the ducts and use splits throughout the house). Companies (for example, mitsubishi) make multizone units that can do heating and cooling in different zones of the house at the same time (if that's required in your climate).

Or in floor heating in the downstairs and no AC.

FISHMANPET posted:

I'm buying the house I've been renting and living in for the past 6 years. We had a home inspection and the inspector pointed out that our boiler is 60 years old and we should probably think about a replacement sooner rather than later.

I'm starting to learn more about boiler/radiator systems, but I'm wondering if there's anything I should keep in mind in regards to brands. At some point I'll talk to hvac companies and get some quotes and stuff, but it seems they each do only a couple of brands so I want to be sure I'm informed to be able to compare different options. Most of what I can find talking about comparing specific brands seems to appear almost ai generated content that I don't really get much info from.

I'm also thinking of doing a ductless mini split system for AC, since we just have window units and since it's radiator heat there's no ducts for central air. So basically same observation about installers and brands, and same question about what brands are good or bad.

Shumagorath posted:

Of course the flow test on the dryer reports 80% blockage anyway because the previous owners let every non-visible thing in this place go to poo poo before selling. At least they won't have to check the transfer hose

Here's the vent joint I was talking about after two loads and me dangling a bunch of paper towel on tongs to look for a breeze:


It looks like it slipped when they moved the machines into position...? If there was a leak I'd expect the flow test to report all clear not a blockage. The rest of the transfer hose looks better than the original.

Shumagorath posted:

gently caress I knew it. I have high-temperature tape and even handed the guys a periscope vent which they did not use. It's a condo so that hose exits the machine and goes to a rigid vent in the ceiling.

That's in a closet with my phone reaching back behind the tower. There's very minimal access to the machines so everything has to be attached and then backed into place, which necessitates a flexible hose. No way am I switching to a condenser dryer / all-in-one after previous experience. The spot previously had 24" machines in it.

PageMaster posted:

Found the vapor barrier on our flex duct ripped while repiping our house. Is this something that can be repaired, or are we just going to need to replace the entire run?



Need to look at our budget but might be a good time to switch in for rigid.

Nitrousoxide posted:

I ended up getting this 12000 BTU model for the summer. It's about 30c outside with the sun pouring in the windows on this side of the house. I'm sitting on my bed, about 5ish meters away and it's happily keeping up with cooling my bedroom (and my entire second floor really because my door is open). Checked some decibel meters on my phone and it says it's about 30-35 DB this far away from it.

Unit is set to 25c and seems to be sipping electricity. I have it plugged into a smart plug that can track the power usage.



So far very happy. Can't really hear the compressor at all. Just the fan, which is all you'd hear with a ductless unit anyway.



I also setup schedules in the app to raise and lower temp at various points in the day. I set it to drop to 22c in the evening because I like to sleep in a cooler environment.

There's also a plugin for homebridge, so you can control it through homekit.

Badger of Basra posted:

I didn't see a question formatting post so let me know if you need any additional information to help me out with this question. Also I know due to labor shortages etc this will either take more time or more money than it would normally. I'm really just trying to get a feel for what is feasible/reasonable to do for my place.

I own a condo in a 16 unit, four story building (no units on the ground floor though). I am on a high first. The building does not have central air so I have window AC units during the summer (it's only hot enough here that I need them from June to mid-Septemberish). These work alright but 1) they are loud and 2) it is definitely still pretty warm even with them on.

I would like to get something better to help cool it but I don't really know what options are available between the end points of "window AC units" and "full on AC system." What are some things I might look into?

Danhenge posted:

aha very cool. I pulled the condensate pump off the unit and the whole pipe assembly wants on the threads inside the drain hole but is indeed glued everywhere. dope

Jaded Burnout posted:

PageMaster posted:

This might be an overthinking it issue, but I finally bought replacement return register grilles for my house only to find out there are two types: fixed bar and stamped. The fixed bar is really nice and light aluminum (though expensive), and I read is much less restrictive to airflow than stamped. Only issue is it slides into the wall opening rather than sit over it, which means it hits the stud and sits out maybe an eighth of an inch:


Is fixed bar really a better option for returns? Is it worth trying to make it work with furring strips or whatever I can figure out? If not I can just throw the steel stamped one over the opening:

zenintrude posted:

Thanks for the response!

I’m in a high rise (42 floors) that was built in 2008 and I believe the A/C unit was installed at the same time. It’s in south Florida, so some elevated humidity is to be expected. The air inside the condo ~feels~ less humid than in the hallways (it’s also cooler) so perhaps it’s just the outside air factor… the A/C unit is in an A/C closet that is not in the condo itself but off of the hallway.

I don’t have too many windows/doors - just one large floor-to-ceiling sliding door out to the balcony with two other fixed windows adjacent to it and a sliding window in the bedroom - all are heavy duty, hurricane grade stuff. Maybe humid air from the hallway is coming in through gaps in the front door? Is there a good method to test for this?

Given the age of the unit, would the A/C need servicing? I checked the filter and it looked (to my eye) to be alright but I’ve ordered some new ones for peace of mind. I’ve also been running a dehumidifier since last night that has captured about 20 pints of water in 14~ hours.

emocrat posted:

Hello HVAC thread, I have a renovation project I am working on and the HVAC component is causing me some trouble. So, gonna make an effortpost here about what I am trying to accomplish and hopefully I can get pointed in the right direction.

Current situation: I am renovating a room in my basement that is 20x21. 3 sides are exterior to the home, the back wall is 100% below grade, the front wall is 50% below grade and the side sloping between. 4th wall is an interior partition. This room will end up being a general play space, about half a home theater, a quarter a bar and the last quarter open space for my currently young kids. This room currently is served by my existing central air system, it has 3 supplies and 1 return.

What I am trying to accomplish: First, I would like independent temperature control of the space. Past experience has shown that when you have a lot of people watching a movie, 10 bodies or so, plus a projector lamp and av gear etc, the space heats up a lot. So, being able to cool the room well without freezing the rest of the house would be great. Second, I am attempting to soundproof this room pretty well. To that end I would like to remove it from the existing central air system, getting rid of large openings connected by a tube to other rooms is pretty helpful for keeping sound in. However, if I do a good job at the soundproofing, that will also make the room relatively airtight (I know its not completely airtight). So, this means I need a means of fresh air exchange so it stays comfortable and doesn't get stuffy.

So, there is a clear solution here: Mini-split for temp control with an ERV for fresh air. I got some quotes and one company here quoted me $7200 for a heat pump + ceiling cassette with a fresh air exchange (19.8 seer Mitsubishi). The reason it is a ceiling cassette vs wall unit is they say its the only ones they can do that accept the fresh air exchange system. The unit is 22x22 and would require me to do some extensive reframing in the ceiling to use. First, regardless of other factors, is this a reasonable quote for what they are offering?

Next, is that even a good way to go? What are some alternatives? I look around online and I see some (admittedly sketchy looking) single room ERV's that would be simple to install. I also see things like this:https://www.ecomfort.com/Panasonic-Ventilation-FV-04VE1/p32041.html that don't look too bad either. Seems like pairing that with a simpler wall unit mini split would work.

Regarding mini splits, there seems to be a market for DIY friendly units. They are much much cheaper than anything I have been quoted. Are these units absolute trash? or are they decent enough to use for something like this? I would be very interested in the experiences of anyone who has gone this route.

Any feedback on any aspect of this would be much appreciated, and if there is any additional useful information I missed please ask.

SourKraut posted:

What's the thoughts/opinions on inline scrubbers like this: https://www.airscrubberbyaerus.com

My wife and both kids tend to have allergies to varying extents, so I'm thinking of getting one installed. I assume the filter MERV 10 filter it uses would need to get replaced on 6 month intervals.

Danhenge posted:

At some point before we owned this house, it looks like a rodent chewed into the duct board of our return plenum in the basement. Gross. It's on a narrow end of the plenum, a face about 1x2" in size. Is this the kind of thing that I could reasonably repair in place myself, or do I need an HVAC specialist for it? I was planning on cutting it at the seam and then using the hepa vac we have to clean out what I could see. Some googling suggests that sealing up duct board might be trickier than it looks, especially given that one side doesn't have much clearance from the wall (maybe an inch).

SourKraut posted:

Our home office gets to bake in the sun every day with two exposed walls, and it's the furthest run on our central AC system and so it typically doesn't get cool enough, while the rest of the house is fine. Our unit is a few years old and the rest of the house is comfortable, and we've tried doing adjustments to the dampers, etc., without much luck.

I'm thinking of having a ductless mini split installed just for this room. It'd just then be supplemental to our existing central AC system, and meant to help cool the room down further through most of the year. The room is about 140 sq ft, has windows on both sides that see sunlight, and gets used as office/mancave.

I'm in the process of getting quotes, but right now it seems like it'd be about a 9K BTU unit, and I'm usually seeing Daikin and Mitsubishi so far. I've kinda always thought of Mitsubishi as the gold standard for mini split systems, but how is Daikin?

So far, the Daikin systems are running about $1K lower for roughly equivalent specs, but since this is supplemental and not the primary, it seems like the $1K savings could be worth it?

kastein posted:

No worries about screwing up and dropping the thing on someone's head 2 floors down, either.

nadmonk posted:

The LP furnace at our relatively new (to us) cabin was having trouble kicking in reliably and the blower was making a good awful racket.
Guess we found the cause. The squirrels got out.


Have a new blower on there and, perhaps not surprisingly, seems to be working just fine. Don't really need it at the moment, but being without heat in the Upper Peninsula in the winter would indeed suck.

I'm sure we'll want to replace the furnace itself at some point, the one in there is a Carrier 80% efficiency one. Thankfully, my father-in-law does heating repair, so I will have good guidance when the time comes.

nwin posted:

Thanks-this all came up because I was checking out that site for the containment-saw the wifi gauges and went to measure the top thread. It’s closed with some blue stuff (loctite maybe?) and I figured my luck it’s been closed so long that if I try to unscrew the cap I’ll break something.

I. M. Gei posted:

We had a guy come to our house to do an A/C tuneup today and were told that if we ever want to replace our unit — which we're probably gonna have to in the next few years or so — then we're gonna need to overhaul our air return vents if we want it to work with an A/C of 20 seers or higher. Apparently the vents we have now are too small and won't return enough air for a new 20+ seer system to work right.

Ouch.

I don't know if it's possible to answer this question without more deets, but what kind of price tag would we be looking at to replace the vents and possibly move the parts currently in our hall closet into the attic (repair guy also mentioned something about that), in a smallish one-floor house built in the 1960s with central air? Like, figure-wise? Would I be right in thinking it's probably like 5 figures?

nwin posted:

Looking for any advice.

Our layout is a 2 floor house with a minisplit Mitsubishi on the lower level and a central unit on the top level (in the attic). Outside is the big fan and I believe the condenser for both units (I see lines going from the fan to the split and upstairs to the attic).

My problem is this: at night it works super great upstairs, but during the day it seems like it’s not even cranking on upstairs regardless of what we tell the thermostat to do. We can set it for 5 degrees below the scheduled temp and it’s hardly blowing out and definitely not cooling the rooms down. Downstairs works fine 24/7.

The entire system is two years old and was just serviced a month ago. House is well insulated but the sun definitely beats on one of the rooms upstairs during the day-we’ve got blackout curtains but it’s not helping.

One thing I’m wondering: since the central unit is in the attic would installing a fan up there help? It’s obviously super hot up there right now so I’m just curious. Right now there’s just a screened shutter which allows air to flow through but that’s it…and there’s only one of them so it’s not like it’s flowing well.

His Divine Shadow posted:

I noticed last winter that my heat recovery ventilation system was only 60% efficient but it should be more like 80%+. I finally took a look at the attic and yeah, I guess the answer is pretty plain, insufficient insulation around the ducts. I am buying more insulation and wrapping around the ducts soon. I've been wondering if I should dig away and wrap the insulation all around the ducts, or if I should like get bigger mats and lay them over the ducts so that they and the area around is covered like a blanket.

First time I ever looked in here. I thought I had a steel chimney tbh. It's made from some sort of cast masonry instead.



The silver wrapped duct is the kitchen exhaust, don't need to bother with that.

DkHelmet posted:

I've been looking into an ERV install since my house has abnormally high CO2 concentrations. It seems like it's still deeply niche, I only found one contractor in my area who even responded, and they quoted $4500 for my 2000 ft^2 home. I'm pissed off enough to look into just buying one, which is about $1k for 300cfm, and it seems to be generally an easy install where I need two 6" cuts on my return duct in the basement, plus two 6" cuts in my vinyl-over-wood-1993 exterior and a handful of insulated duct.

This would be the first time I do anything HVAC aside from a thermostat. For those who know better- is this in the realm of a DIYer, and are there any good tutorials out there for doing this sort of ducting? I'm wading through the sea of bullshit in youtube and debating calling a professional to handle the ducts.

His Divine Shadow posted:

You know, I didn't write about this because I was feeling pretty stressed out about it. After I went in and looked closer at the blown in insulation I found it was only 100mm or even that. I was flabbergasted, this house had less roof insulation than a british home (I read 200mm there) and it's been like this since 2014.

This must be a mistake I thought, I went and looked at my house blueprints (I got the prints for everything, structure, water, ventilation, electrical etc) and double checked and yeah, I'm supposed to have 500mm of blown in insulation, not less than 100mm! Holy poo poo I've been living since 2014 with almost no insulation, I can't believe we haven't noticed it. The ducts are supposed to be buried in this stuff and not exposed at all.

We have an annual consumption of 11,000 kWh, but that also includes direct electric heating in my shop so I figured that takes 2-3000 kWh on its own and 7-8000 kWh for the house and I thought that sounded OK since our house is electrically heated too, with a heat pump. I am kinda amazed how well it has worked despite all that.

At any rate I contacted the company who built my house and showed them the photos and told them what I discovered, that was friday. They phoned me just now and apologized a lot and they will be sending a truck as soon as possible, inside two weeks and putting 500mm of blown in insulation in my attic.

EDIT: went in and checked our electricity consumption for the last 12 months, 9850 kWh (!), impressive IMO. We did try and save power this year, lowered the indoor temps and used our accumulating masonry heater to get the temps up. It's gonna be interesting to see next year how much this lowers our consumption. I have a feeling we're gonna save a lot of money. I also have a feeling the building company knows that and are happy we're not trying to get them to pay for that....

chutwig posted:

I am playing a stupid game with my downstairs air handler. About a week and a half ago when we were on vacation, I saw that the Ecobee attached to it had gone offline. We got home and I found that the air handler itself was unpowered (the heartbeat light on it was not blinking like normal). The breaker had not tripped, and when I flipped the cutoff switch off and back on it came back on. A few minutes later it shut down again. I flipped the cutoff switch a second time and this time the control board stayed on for about a day before shutting down - heat/cool were off during this time so the blower and such were not actually running at any point.

I got an HVAC guy to come look at the system when we got back from vacation on Thursday. He claimed that he was seeing only 80V on the circuit from the distribution panel, but I didn't see his meter to independently verify that measurement. The breaker in the panel was mislabeled as BOILER so he didn't find which breaker the air handler was attached to - I figured it out after he left. That circuit doesn't actually seem to be attached to the HWH in any way, so it seems to exclusively be servicing the air handler. He told me I needed to find an electrician, which I've been trying to do since then, but finding an available electrician in North Jersey has been impossible for the last several months (been trying to hire one for reasons unrelated to this problem).

Last night it seemed to be working okay and the A/C was running when it shut off again. I decided to begin investigating the problem in more depth myself. I was somewhat suspicious of the condensate pump because I hadn't heard it running in a while. The wiring inside the air handler is shown below:



The white Romex on top is from the breaker panel, the black cable below that has the wires that go to the condensate pump. The wires that run off to the left are the ones for the air handler. There are no other wires running to the condensate pump.

The condensate pump tank was quite full, which added to my suspicion that it was not working properly and was responsible for these shenanigans somehow. I unwired and removed the condensate pump, emptied the tank, cleaned the internals as best I could, and hooked everything back up. When I turned the breaker back on, the air handler did not show any power to the control board at all. I removed the condensate pump from the circuit entirely but same result.

At this point I'm pretty confused. I don't have a voltmeter or even a voltage detector pen at the moment, though I plan to get one, but messing around with live 120VAC to test voltages is at the edge of what I'm comfortable doing. We have a sump pit now so what I'd like to do is just remove the condensate pump entirely and run tubing into the sump pit to drain the condensate, but I am perplexed by these compounding weird electricity issues.

chutwig posted:

It looks like some part of the old switch had started to slowly overheat/melt over time:



If backstabbing is what the Internet tells me it is, the wires on the switch were all anchored to the screws; I don't know why that little piece of copper wire at the far end of the switch is protruding from the back like that.

I replaced it with a new switch and the air handler came right on.

nwin posted:

Yeah they’re coming out Thursday-soonest they can get here given we still have hot water. I’ve got a drip cup underneath it and I guess I’ll wait to see what they say.

Edit: a couple hvac techs on Reddit are saying it could just be condensation since I’m not running the heat yet and just using it for hot water. It’s 50 outside today so that seems possible. I figure I could turn the heat on and see if the dripping stops.

Comrade Gritty posted:

I assume if your propane furnace exhaust has a giant hole in it you should not run it yea?

Rescue Toaster posted:

I just turned on my furnace today and I feel like there's a vibration that's associated with the combustion air blower instead of the main blower. You can basically feel it through the floor through your feet when it first kicks in and starts heating up, and then noticeably it stops ~20 seconds before the main blower does when it cycles off, so it must be related to the actual combustion system. I didn't notice anything with the AC running a few weeks ago either.

But it seems weird, the combustion fan is much smaller than the main blower, and there's no sound like a bad bearing or anything. It's as if it went out of balance on its own somehow? How the hell would that happen?

The only other thing I can think is they replaced my gas meter a few weeks ago, and the water heater has been fine, but could there be... I don't know, trapped oxygen doing something weird in the line causing a pulsating effect? Probably a ridiculous idea.

H110Hawk posted:

I have spray foamed the hell out of a lot of copper pipe cavities in my house. I'll let you know how it goes. Once a can is open I can't help myself.

BonoMan posted:

Calidus posted:

I have one more stupid question, I have been told by the house inspector and the hvac tech who installed my new AC (two different companies) that the existing furnace is oversized for my house. Is adding duct work with dampers to a garage a thing?

Edit: it just dawned on me that with no return vents everything probably gets screwy.

Yooper posted:

Geothermal heat pump in this case. I don't trust much the PO did (who had this installed) so I've been concerned it is undersized.

Agreed in regards to the new info, there's a lot of it and I don't have context to compare it with. Maybe next winter it'll give me a good snapshot.

Dr. Eldarion posted:

Not sure what the measurement was, the instrument was yellow and had some sort of scale with a series of LEDs on it. It only lit up the top, red LED that said "bad". I should have paid more attention but I was too busy being confused about the capacitor. I've been trying to Google for it, but can't find anything that looks like it. Definitely looked like a commercial product though, not something just hacked together or something. I know this is a worthless description and I feel dumb for not getting more information.

Yes, there are no evident problems at the moment. All of this stemmed from a regular yearly maintenance. It was just on for an hour and a half without any issues. Starts up fine, runs fine, cools adequately, fan seems normal from what I can tell.

Edit: if anything, the biggest takeaway for me from this is that I really need to start asking more questions and taking notes