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Motronic posted:LOL, now there's one I hadn't seen before. Yeah, the 4 ton condenser, just the condenser is over 5 grand. That doesn't include the branch box to give it zones, or anything else. Around here you can find someone to throw in a basic heat pump system for 6 grand or so, so this setup would probably 4 or 5 times as much all said and done. Risinger only builds high end homes though, he won't even talk to you unless you have an architect and are building a 1M+ dollar home. His building science stuff is neat though.
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Jul 25, 2022 15:41
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It's baffling this even exists. At these price points it makes absolutely no sense and has no benefit I can determine - in fact there are a lot of negatives beside price.
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Jul 25, 2022 15:46
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Commercially, I install VRF systems with multiple units on one condenser all the time. It requires a heat recovery box (each manufacturer has a different name for this box, but they all do the same thing). It allows one unit to run in cooling and the other heat mode at the same time. You essentially get "free" cooling in this mode as you're just transferring heat from one part of the house to the other, but this situation doesn't happen all that often. Also lets you run one unit while another is off. You can also get condensing units with multiple ports so you can run two terminal units off the same condensing unit, but they both need to run in the same cooling or heating mode, can't switch between the two. Both of these are common for things like apartment complexes or condo buildings, but I doubt they get installed much in single-family homes.
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Jul 25, 2022 15:55
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Jaded Burnout posted:You perverts are gonna love this one. This is amazing and you are a hero for making this work.
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Jul 25, 2022 19:04
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Rissinger is a huckster imo. Some of his videos are good but I always watch them with a pinch of salt because he's always selling you something.
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Jul 25, 2022 19:12
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I'm in the middle of a home renovation and have come to a point where I need to make a decision about HVAC stuff. Thankfully everything is functional enough at the moment so I have some time to figure it out. I live in a townhouse in Houston. Built in the early 2000's: 3 stories tall, lofted ceilings, giant windows so plenty of solar gain (though the reno is addressing that with some low-e windows) HVAC is in the attic above the third floor. Plenty of room between floors to run ducts, as it is all web joists. Everything is insulated flex duct. The existing system is controlled by 3 thermostats linked into a very basic (read: terrible) zone controller. 2 dampers, probably both original. No bypass that I'm aware of. The house apparently came with a builder special (4 ton?) AC when it was built. PO replaced it with a 5 ton: condenser in 2009, coils in 2017. Gas furnace (3 burners) and blower are original from 2000ish, and there was a good bit of adapting from one size to the next to get it to fit together. I'm doing a remodel of the main (2nd) floor and and at minimum will be moving the duct chase, but am thinking that while I have walls open and such I might consider different options. Right now the master bedroom on the top floor gets about 5x the airflow of anywhere else in the house, so keeping the main floor cool ends up freezing the master bedroom with usually a 5 degree differential. If the ground floor is being cooled, it is even worse--with the ground floor at 75 the master bedroom will be 68. Same with heat when that occasionally happens, but worse because heat rises. The range of options I'm looking at would be: 0. I'm definitely going to be re-routing the supply and return for the ground floor, reducing both of those runs by ~10' and the 2nd floor return duct by about 6'. Further options would include this. Maybe also increasing the size of the ground floor supply to increase airflow there. 1. Replace the old furnace/blower with a new gas one, sized to the existing AC. Keep the old AC/condenser. Replace zone controller and thermostats. 2. Replace the whole system with a heat pump. Probably a 4 ton/whatever BTU because the existing one cycles on and off constantly. 3. Go to a mini-split for the ground floor, separate normal AC or heat pump for the main and top floors. 4. A multi-headed split heat pump system for the entire house. I'd really like to get rid of the gas furnace because it is the only thing in the house using it and paying the minimum charge 9 months of the year just to keep it for the three weeks I need it bothers me. This seems the best time to do any change, as I'll save not only the monthly fees but the cost of having a licensed plumber relocate the gas line. I had one well-recommended AC guy come by to give a quote (still waiting on that), but it sounds like he specializes in AC/gas heat systems and didn't know about options for mini-splits more involved than the generic wall-mounted things. Has anyone had similar options quoted out? I'm seeing places saying that a heat pump will cost ~1.5x what an AC does, but I don't really know much about what that's going to mean from an end-cost perspective. Good rules of thumb on how long components generally last and such would also be nice to have for trying to balance the systems as well.
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Jul 25, 2022 22:29
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So I’m replacing a roof mounted package unit with a split system to make room for solar panels—trying to figure out what makes the most sense for me. - Southern California (San Fernando valley) - Single story, 1400sqft - Currently have a 5ton rooftop package unit - New system needs to work with my Ecobee Biggest issue right now is that the current system is pretty oversized for the house, so when the AC kicks on it blasts cold air out of the vents for a few minutes and rapidly cools down to the setpoint. The jet of air is pretty uncomfortable when you walk in front of a vent. It also makes balancing airflow to the various rooms pretty tough—even with dampers in a lot of the vent runs, it’s just super inconsistent room to room (there’s very little time for the air to mix in the house). sooo, I’m thinking I want a two stage compressor system with a variable speed fan in the air handler? I can run it longer at low stage, and a low fan speed right? And it’s still compatible with the ecobee? The quotes I’ve gotten so far (that would be compatible with my ecobee) are: - a 17seer 4ton slimline daikin (branded as NexGen) single stage with multi speed fan, $22k - 16-18seer ACPro (rebranded Lennox) x series, inverter compressor. This appears to be a variable speed compressor that’s designed to work with a standard 24v thermostat. Not sure if the air handler has a variable speed fan (waiting for a part number to confirm) but seems like it would have to be, or it can just be set really low to let the thing run longer because it’s a variable compressor? $19k for this one. https://store.acpro.com/ac-pro-x-series-condenser-air-conditioning-42-000-60-000-btu-73234 Still getting more quotes, but it seems like the ACPro is the right move? Any suggestions?
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Jul 28, 2022 03:21
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I would find the manuals for the "smart thermostat" compatible mode to see if it actually does what you want. My carrier greenspeed variable is also "compatible" but it turns it into a two stage. I have never seen a residential variable condenser/fan unit that has a published protocol spec to let a 3rd party take advantage of it. It might try and ramp up and down speed based on how long the cool call lasts but that's going to be a much different experience than a communicating thermostat
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Jul 29, 2022 14:28
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So I know that sqft to ton is not how you do it but  5tons for 1400sqft? That seems like at least 2 tons too many. I would insist on someone doing a manual j. It seems like if you actually need 5 tons you should spend some money on insulation and sealing up, likely all of which would come from the reduced hvac size.If you have single pane windows that might be a big contributor but that's another ballpark in costs and solar would knock down your operating cost. Consider uv film. 
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Jul 29, 2022 14:54
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I was at 4 tons for 1400sqft in AZ in a ~2000 build with no massive air leaks and you needed all four tons in the worst of it, for sure. I'm at 5 tons on 1800sqft now in a different but similar ~2000 build. LA area should be somewhat better but not by a huge amount, poo poo gets plenty toasty there too.
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Jul 29, 2022 16:46
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IOwnCalculus posted:I was at 4 tons for 1400sqft in AZ in a ~2000 build with no massive air leaks and you needed all four tons in the worst of it, for sure. I'm at 5 tons on 1800sqft now in a different but similar ~2000 build. Yeah, I'm in a toasty part of LA and it's just surprising. This is why me shooting from the hip about tonnage to Sq ft is a dumb idea it's just surprising. Are you well insulated walls and attic? Double pane windows?
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Jul 29, 2022 17:14
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Both my old and current houses seem to have typical insulation of the era - not great by current standards but there's no toasty-hot walls in the summer. All double-pane windows and both also have minimal windows facing east/west/south. Insulated in the attic as well, not that I've ever been up in either one longer than just enough to look around and climb back down the ladder. Going to a two-stage (on the old house) / fully variable (new house) heat pump was definitely worth it in terms of overall comfort, though.
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Jul 29, 2022 17:29
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the poi posted:
Qwijib0 posted:I would find the manuals for the "smart thermostat" compatible mode to see if it actually does what you want. My carrier greenspeed variable is also "compatible" but it turns it into a two stage. I have never seen a residential variable condenser/fan unit that has a published protocol spec to let a 3rd party take advantage of it. It might try and ramp up and down speed based on how long the cool call lasts but that's going to be a much different experience than a communicating thermostat the manual was linked at the bottom, and it is a variable speed compressor-- but you set it to a single speed at install. It appears to be designed as a single SKU for easy stocking. The installer will set the tonnage to 2,3,4 or 5, and at that point it's a single-speed unit. it only has an R, Y and C connection to the indoor components, so that's compressor on/off and a common wire only.
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Jul 29, 2022 17:53
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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?
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Jul 29, 2022 21:31
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5 figures easily, you're probably close to that even with just an equipment swap at a lower seer that might be fine with the flow restrictions. Attic work sucks and will be charged as such.
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Jul 29, 2022 22:07
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Why would you replace your entire return? If you need more return, I would think you could just add one more return grille somewhere in your house, which really shouldn’t be much money.
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Jul 29, 2022 23:03
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Bird in a Blender posted:Why would you replace your entire return? If you need more return, I would think you could just add one more return grille somewhere in your house, which really shouldn’t be much money. Especially not in a single floor house.
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Jul 29, 2022 23:07
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Bird in a Blender posted:Why would you replace your entire return? If you need more return, I would think you could just add one more return grille somewhere in your house, which really shouldn’t be much money. If adding one return grill is all we need to do, then great! The repair guy told us we'd need to do more than that, but he might've been an idiot. He also said something about energy regulations being nothing more than a way for the government to steal money from people, sooooo...
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Jul 30, 2022 03:11
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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. Is your house built on a slab? We also have a 60's era house with the AC in a closet, and it uses ductwork built into the slab. If so and you wanted to move the system to the attic you'd be looking at entirely new ductwork for the entire house. Ductwork in the slab is pretty lovely for a bunch of reasons, so it might end up being worth it!
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Jul 31, 2022 15:25
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Called out a guy to fix the AC yesterday (one of two units). It's a nice unit, a 13 SEER Trane heat pump from 2016. Condenser was making noise and spinning the fan, air handler was running, but the air wasn't blowing cold. Guy showed up, swapped the capacitor with one from the truck, and it fired up immediately. Took him less than 10 minutes to do the work and check that the refrigerant was in spec and then another 10 minutes to write up the bill. $300 for the part, $125 for labor. $425 later, the upstairs AC works on a 100 degree day, I definitely got off cheap. Looks like online the actual part cost is $20-30 or so. I get that there's a markup on parts and the line item pricing is all a shell game to obscure overhead and admin costs, so whatever. Not mad about it. I didn't know what to do or have the part to fix it and that isn't something that I can wait around for. What I want to do is buy a replacement capacitor for each unit to keep around in case this same issue comes up again with the unit's brother who was also installed at the same time. I am having a very hard time finding a part number or spec online for the capacitor. Trane's documentation is minimal for owners and just constantly references calling a licensed pro. Besides pulling the panel off and looking at the existing capacitor, are there any resources or places online to help me identify what I need?
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Jul 31, 2022 21:30
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canyoneer posted:Called out a guy to fix the AC yesterday (one of two units). It's a nice unit, a 13 SEER Trane heat pump from 2016. Condenser was making noise and spinning the fan, air handler was running, but the air wasn't blowing cold. That is definitely the high end of a cap swap callout. Mine were under $200, also 100F outside. What you want to do is exactly what you should do. Turn off your thermostat, go out to your unit with a philips and hex head driver, pull the fuse/kill the disconnect that is within arms reach of the outside unit, unscrew the access plate, and look at the capacitor. Take a picture of the whole thing, and if there is a sticker inside the access panel take a picture of that, and take a picture of the "plate" on the outside of the unit (make, exact model, serial number. We're not looking for the Trane Cooler 9000XXLLLL but the "T9000Xl19w99ssiuh1999" model number that decodes into an exact set of options. You're looking on the cap for Volts and Micro-Farads (μF or uF). Don't touch the contacts and really really don't bridge them.
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Jul 31, 2022 21:55
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I had an HVAC guy tell me my power absorber was going and that he had it on the truck and could replace it for $500. I've been doing commercial building maintenance for 14 years and while I am no HVACologist, I know what's going on in a residential condenser. He eventually admitted it was a capacitor. I get why he does that but it seems to really exploit people when they are in a bind. canyoneer posted:I am having a very hard time finding a part number or spec online for the capacitor. Trane's documentation is minimal for owners and just constantly references calling a licensed pro. Besides pulling the panel off and looking at the existing capacitor, are there any resources or places online to help me identify what I need? You should definitely take a look at it. If you're not comfortable with safely taking the panel off then you might have problems when you have to swap it out. It will be right there and it's hard to miss. From a forum post, I found this image of what should be your unit (do not trust the internet). NC Wyeth Death Cult fucked around with this message at 22:13 on Jul 31, 2022 |
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Jul 31, 2022 22:11
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The two parts in that photo, the contactor (left) and capacitor (Right) are perfectly reasonable spares for a handy homeowner or maintenance persons to have on hand, especially for units over 4-5 years old. they are relatively inexpensive, and generic equivalents are usually easy to source. if you are technically proficient enough to use a screwdriver, and wire-for-wire replace a thing (with the power turned off at the breaker), there is no special equipment needed for the repair.
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Jul 31, 2022 22:54
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Hay goons, have you cleaned your loving condenser lately? No? You should probably check that poo poo out. I paid to have it cleaned on a service call 2 years ago. I have my fuckin doubts tho. Just call it a hunch.
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Aug 1, 2022 00:55
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Elmnt80 posted:Hay goons, have you cleaned your loving condenser lately? No? You should probably check that poo poo out. This is how my condenser coil looks every year when I clean it. Although this year I invested in a foam sprayer and proper coil cleaner to hopefully get it extra-sparkly clean this time. e: I'm not even exaggerating. Here is the picture of before I cleaned it last year. 
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Aug 1, 2022 01:16
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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.
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Aug 1, 2022 01:47
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nwin posted:Looking for any advice. A minisplit + regular AC on the same condenser seems pretty weird to me. Not in that you can't do it, but it's an unusual setup. Is the upstairs unit moving the same amount of air at night versus during the day? If not that's... weird. It's possible you've got a timer or similar setup that's forcing it to low speed (maybe someone incorrectly connected the dehumidifier controls, which typically slow down the fan speed?) My other thought would be some sort of timed damper that's opening during the night that's leaking air.. somewhere? Can you access the upstairs unit? It may have some sort of status display that shows what it's trying to do, which would be your next hint. More ventilation in the attic can't really hurt, but it's not going to do anything if the issue is airflow (and not temperature)
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Aug 1, 2022 02:37
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Can we get some model numbers here? Because they do make multi-head split units, one could simply be ducted. What's the thermostat on this stuff?
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Aug 1, 2022 02:41
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So the PO said he installed it this way because he didn’t like the aesthetics of having mini splits on the top level. That is literally all he gave me. For pictures and model numbers, this is what the mini split on the lower level shows:  Here’s the unit outside:  No pics of the unit in the attic yet. For the thermostats, the minisplit is controlled via a remote control-similar to this: https://youtu.be/rmIaFkkG7lU Upstairs thermostat is MCRH2: https://shop.rfwel.com/mitsubishi-mrch2-wireless-remote-controller/  I haven’t been up to the attic in a week but it looks like a big box with 3 ducts that go to each bedroom upstairs. I know that probably doesn’t help. I can say it does NOT look like the minisplit downstairs though. nwin fucked around with this message at 03:12 on Aug 1, 2022 |
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Aug 1, 2022 02:57
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https://www.ecomfort.com/Mitsubishi-MXZ-5C42NA2/p68693.html That's a multizone unit. Look at the compatible indoor units - some of them will be ducted. That's what you have in the attic dollars to donuts. Something is programmed wrong if it's just refusing to cool adequately during the day assuming at night it's blasting cold air at a good velocity. What happens if you turn off the downstairs unit and crank the upstairs one during the day? Let's see that thermostat of yours.
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Aug 1, 2022 03:03
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I've read that some of those multi-zone units can also use each head as a condenser/evaporator and move heat/cold from one part of the house to the other instead of using the outside condensing coil. Is it possible that maybe it's configured to do that?
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Aug 1, 2022 03:11
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H110Hawk posted:https://www.ecomfort.com/Mitsubishi-MXZ-5C42NA2/p68693.html Posted updated thermostat in my op, it’s the MCRH2. You might be onto something…we programmed the downstairs split to turn off at 8:30 pm each night so it makes sense that the ac is working great upstairs in the bedroom when we come up here at 9/10 pm…but since that’s only two zones I’d hope it’s able to tolerate both at the same time.
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Aug 1, 2022 03:14
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Your downstairs unit is 18k out of 45k. Which should be totally fine. Tomorrow turn off the downstairs unit and see if your problems all vanish. You might have a serious charge problem in your lines.
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Aug 1, 2022 03:21
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I have had customers that never clean theirs, ever. (On top of tall building) and others that need it multiple times a season, because they are located next to a cottonwood field. ymmv.
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Aug 1, 2022 03:23
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SpartanIvy posted:I've read that some of those multi-zone units can also use each head as a condenser/evaporator and move heat/cold from one part of the house to the other instead of using the outside condensing coil. Is it possible that maybe it's configured to do that? almost nobody installs those for single family residential because they are extremely expensive for no payback. his model numbers indicate a regular heat pump system. H110Hawk posted:Your downstairs unit is 18k out of 45k. Which should be totally fine. Tomorrow turn off the downstairs unit and see if your problems all vanish. You might have a serious charge problem in your lines. Its probably this.
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Aug 1, 2022 03:33
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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. His Divine Shadow fucked around with this message at 05:15 on Aug 17, 2022 |
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Aug 1, 2022 07:59
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canyoneer posted:I am having a very hard time finding a part number or spec online for the capacitor. Trane's documentation is minimal for owners and just constantly references calling a licensed pro. Besides pulling the panel off and looking at the existing capacitor, are there any resources or places online to help me identify what I need? H110Hawk had good advice for finding the part number/specs you need. While you're in there, try to get the part number/specs for the contactor. Those are two of the main points of failure. And they're dirt cheap to buy and keep on the shelf instead of getting soaked when they go out and you have to service call. I replaced my contactor in 2016 and had a couple capacitors over the 15 years I've been here. Always replaced myself and it's been running. But today I have 3 different companies coming out to quote a furnace/AC replacement. This 23 year old Trane unit has done very, very well, but it's tired, uses R22, and just isn't something I can confidently rely on anymore. Current is a 3 ton for a 2800sqft house with vaulted ceilings. Seems love by at least a half ton. Currently airflow in the upstairs sucks because builders don't give a poo poo about return air and it's way too much flex pipe. First round is Trane / Lennox / Goodman. I'm having a hard time seeing how Goodman is a bad choice with a 10 year warranty, since my horizon for this house is less than 10 years. Thoughts?
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Aug 1, 2022 11:51
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EVERYWHERE 
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The problem with goodman is they shoot for the lowest price point at each marker segment, so you get incompetent bottom dollar contractors installing them incorrectly. The equipment itself really isnt that bad.
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Aug 1, 2022 15:21
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MRC48B posted:The problem with goodman is they shoot for the lowest price point at each marker segment, so you get incompetent bottom dollar contractors installing them incorrectly. The equipment itself really isnt that bad. The problem I've found with Goodman is that they'll sell to anyone. The rest of the brands - for better or worse - require an authorized dealer network that provides for some kind of competency in selection and installation, although it seems increasingly that it's still not enough. But at the very least it's an established HVAC company who can supply this equipment as opposed to the last refuge of plumbers and handymen doing HVAC: Goodman. I think you're a resi person so I'm probably not telling you anything you don't already know.
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Aug 1, 2022 15:25
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Motronic posted:The problem I've found with Goodman is that they'll sell to anyone. The PO of my home tried to install his own in a crawlspace and gave up halfway through the install and hired professionals to put in a completely different geo system in the basement. So now my garage has a super sweet Goodman 98% unit.
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Aug 1, 2022 15:31
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