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Okay uh there actually is a question now That I look back here Um R134a says does Stephen have a long-term Update on the Bosch inverter systems he Installed you know we had mentioned that I was like are we gonna talk about Bosch Again it's like blah blah you know uh do You have any updates on the Bosch stuff Um Bosh bad Bosh good Bosh better what do You say it's been sort of a non-issue Since we've got our systems dialed in Um well how'd you do that that'd be That's news right there let's let's talk About it well Um change them out we put Um I think I had mentioned in one of our Earlier Um maybe not last year but the year Prior to that Um We put um Dehumidifiers in with most of the Systems that we put Bosh in or houses we Put Bosh in Um a couple of other ones we put in Reheat thermostats Okay Um that use the auxiliary heat to act Like a dehumidifier Um and then we staged the blower speed Um basically told the air handler that It was a two-stage unit even though the
Bosch is not Um the first one you're talking about The first series of the second series Um all of mine were first series okay Um originally I've touched two second Gens since then Um one I installed under duress and the Other one I just happened to have a Customer that has one Um but staging the air handler on the First gen Bosch To give the blower two different speeds Actually works pretty well For managing latent capacity because it Keeps that coil as cold as humanly Possible basically we ended up running About 150 to 200 CFM per ton for stage one That's 150 to 200 okay yep all right and Then for stage two somewhere between two And three hundred CFM per ton Um when I had originally set up the Units I had nailed airflow based on the Capacity like 1200 CFM for three tons Or you know closed without going over Um And that turned out to be absolutely the Wrong Setup because They sucked Or didn't suck all right let me let me Ask you something all right you start Out at 1200 like a normal system would
Be like then let's use that term loosely Because it varies so 1200 CFM 400 CFM Per ton but for Boss you got to lower it Down because you're taking that sensible Capacity and you're transferring it to Latent capacity and trying to find a Sweet spot Now how difficult was it to try to find A sweet spot when you still have to Bring the actual temperature down as Well Do you have trouble getting the Temperature down no once you changed Them okay no they've nailed Temperature control just fine Um Early on in our debacle I had reached Out to Bosch and they had a field tech Rep come out and we went over this one House and he said set your airflow to 200 CFM per ton And that was at the time pre-2 stage Thermostat discussions pre- everything He said don't change any of the dip Switches set your airflow to 200 per ton And I was like that's ridiculous But I did it because that's what he said Needed to be done Despite not agreeing or understanding it Um that's what I'm concerned about how This like uh the treatment for the issue It's it's an afterthought is what it is It's like well this thing don't work Right so here's what we have to do to it
To try to make it work right that's what It comes off as and there's a there's a Plethora of advice in the chat about how To do it correctly I've I found that Once I zoned it and used the ewc board As the brain for the system to limit When it runs as far as staging it does Much better yeah that's almost like this This brain outside needs another brain To tell it what to do is what it seems Like to me Almost Which is bad because Well I think yeah you know what's funny Is that there's a bunch of guys who are Coming up with stuff and it all sounds Really good and then Ted Pops in there And says the 2.0 is great when you throw It in a dumpster I thought that was Funny that's funny but you know I have Made mine work but you know with every Cut of airflow the capacity is lower and Lower with every minute you make it stay In first stage when it needs second Stage I mean it's it's causing it for long run Times it may be real long like all day Long you know that sort of thing so it's Just I don't know it's it's Humidifier so that's crazy you know yeah I recently put in a system called smart AC Um it's a monitoring Hardware and software for performance
Um it was touted really big at the HVAC School Symposium that uh HVAC school does that makes sense Um But when I looked at the run time Between my system which is a xv20 Um which is variable capacity compressor Variable speed blower train Um For those that don't know train numbers Um I have literally 22 to 23 hours of run time On a variable capacity compressor I've got my friend that I mentioned Earlier has a 24 year old single stage Goodman He was showing seven minute Run cycles Not good Um And I told him because he was like so What do you think I should put in and I Said I think we should put in a two-ton XV He's like don't you think that it being A three-ton now means they'll be a Little shy I said no You got seven minute Run cycles you'll Be fine seven minute runs and okay again Let's pretend like your people it's like Their first day seven minute Run cycles Is bad why well one it's the steady State of the air conditioner doesn't it Doesn't reach it in seven minutes no so
It's like it's never reaching the proper Point Um and you have the Goodman which is Going to be pulling 1 million amps on Startup and it's probably leaking Refrigerant anyway because it's Goodman So you have all sorts of problems anyway I just want that in there go ahead yeah I mean I'm seeing one of the beautiful Things of measure quick that I like so Much is that you see that startup Information like You put your probes on you start the Stupid thing up And you get to watch it learn or figure Out where it wants to run And You can see that on a seven minute Run Cycle that system is nowhere near to Steady operation I've had systems that I've checked on a mild temperature day This spring That Literally ran zero so superheat On a TXV For 10 minutes Until the refrigerant got Positioned The sub cooling will be in the right Place sometimes but the superheet will Sit at zero for 10 minutes and then give It another five minutes and the super Heat starts coming up Yeah that's that's with pistons it's
It's it's awful I mean it's it's really Bad I mean you see a piston unit if you Think you're checking in the first Minute or two you'd be like why is the Pressure back in R22 days yeah well it's A pressure of 45 PSI this thing's Leaking it's like let's just wait a Minute yeah like you come back in three Minutes and that's 74. so I was like Okay all right in five minutes of Changing and so on and so on Um there's a good point Eric Eric Kaiser Says air conditioners don't remove Humidity if they aren't running long run Times can be in Greater humidity or Removal so let's take that statement Talking about your XV unit your XV unit Is matching indoor and outside not Matching like age all right but matching Like the capacity outside is being Intelligently communicated with the Blower capacity inside what speed the Blower is running so when it's less Capacity the blower speed goes down The Bosch it's not it's not doing that Unless you fiddle with it it's you had To tell it to do certain things you have Variable compressor speeds with the same Blower speed So the dehumidification capability is Not the same to me there's a two Different types of treatment it's not Like you agree with that but see if you Agree with this one
You have these machines that have let's Say it has a three ton coil you run at a Capacity of 30 percent maybe 50 percent You have that three ton coil now you Have 18 000 BTUs of action theoretically Going on all of a sudden the efficiency Of that coil skyrockets and Dehumidification capability plummets to Me that would be the case What do you think It could run a long time and still Dehumidify but if it were running let's Say a full capacity constantly for that Same period of time there'd be way more Dehumidification taking place yeah Uh nothing you can do that to be cold be Really cold right Um one thing that I saw When I had my Um What was it called It's now Scentsy predict Um I can't think of what it was called Before But it was a monitor for amps volts Thermostat Um signals Line temperatures and air temperatures Um one thing that I noticed I was Watching my brother's Bosch which I put In Which she's in Ohio it's a totally Different Market
Um he never complained about humidity But I don't know If he should have Um But I watched the amperage on the bush Because that amp monitor with the Scentsy predict Comfort guard that's What it was back in the day on the Comfort Garden you could watch inrush And you'd see a million amps Theoretically on a standard system but On the boss you'd see a little startup Amperage And then over the Run Cycle it would Start off at like three or four amps And then it would just creep up now this Is all 1.0 so they may have changed some Of the algorithm in it but It would literally start off low And then depending on how long the Thermostat called it would Gauge up until next call ended and then Of course it would shut down And my thought process when I saw that Was they're basically getting efficiency Because they start at 9000 BTUs Regardless Because they have nothing to base it off Of there's no intelligence in the Controls the thermostat or anything you Could have a literal stupid light switch On the wall to turn it on and so they Get their efficiency by starting at 9000
BTUs And letting it run as long as it takes For that compressor to eventually ramp Up and deliver enough BTUs to shut it Off But if you like you said if you start Off with 9000 BTUs on the condenser and A three ton evaporator You've got nothing for humidity control Like right nothing because the ratio of What it Um The suction pressure and just the Relation between the dew point and the Apparatus it changes so much but that's Why we have the like your eye manifold Guy the Delta on the evaporator if it Gets lower it's more efficient it also Sucks at dehumidifying in a normal Environment like we would be in so that That was my concern with it I mean the Deltas found a shrink Thus it would be worth it dehumidifying And it overcomes that in many cases by Being Running a long time yeah that makes Sense to me what doesn't make sense to Me is if the Bosch has like Erica Sanders two different points like the Airflow let's say the airflow is you can Change it to a certain degree there's Five speed tabs I think on the x13 motor But even if you chose the lowest ones That's two points
At which it's going to deliver capacity Based on those two airflow points but Your XV has I don't know how many but a Lot more than that oh yeah so when the XV be a lot closer to matching what you Need than the boss you mean the Bosch Would be better than like a single stage Unit sure but nowhere near the XV yeah That's how I imagine I mean I can't Imagine the XV operating like my boss Did the first summer right I mean you'd have to have a really Horrific install for an XV to act like a Boss You'd have to really booger some things Um You can still oversize variable capacity Because just because so one of the Things that I've done with my business Is think backwards of what I've always Seen happen If you have a three and a half ton System And you want two-stage or variable Capacity you have to go for an even ton Three or four In every situation where I have taken a Half ton unit and dropped it down We have seen incredible comfort and Efficiency for the customer The only job where we went way Aggressive we actually dropped it a full Ton Was a job where the customer wasn't able
Or willing to spend to fix ductwork that Wouldn't fit a three ton to begin with And we actually went from a three ton to A two ton And the only drawback Is that instead of using setbacks which Isn't really a drawback instead of using Setbacks they have to maintain their Evening temperature 24 7. because it Can't overcome A hot house in the middle of the day in The evening but if you set it at 70 Degrees It'll nail it all day long But it can't come back from like a 78 Degrees during the day down to 70 Degrees in the afternoon Because the xvs really are not designed To do that they're literally designed Set it forget it and just let it Modulate all day long Foreign [Music]
