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This video is brought to you by Beckett HVAC pump Solutions you can trust Learn more at beckettus.com forward Slash Industrial On a previous show I had talked about Heat pump performance in cold weather And how on very basic especially older Heat pumps up to basic modern heat pumps They perform very poorly when it gets Cold outside somebody in the comments I Don't remember who it was because I'm Going off my memory here which is right 50 of the time had mentioned my Particular heat pump which is a Bosch Variable speed heat pump kind of wanting To compare between the old ones and a Variable speed heat pump so I was Looking through the internet I didn't Feel like going up in my attic I guess To get the actual manual I was looking For the specs it took a while I found Everything but what I needed but I found The specs for the Bosch heat pump so I'm Going to show you guys what they are and I'll tell you podcast guys what I'm Looking at here and we'll compare the Performance of a variable speed heat Pump like the Bosch With an older single stage heat pump So what we're looking at on this PDF is Heating performance data from the Bosch IDs 2.0 Bova unit which is the outdoor Heat pump this is the Bova 36 which is What I have plus the bva 36 for heating
I think that's the indoor coil but it Works the same for making this point We have a three ton unit matched up with A three ton coil Along the top of this chart you see Outdoor dry bulb temperature it ranges From 72 on the left all the way to Negative four What we really want to find out is what Kind of performance do we get at Negative four and reading over the Manual it looks like the Bosch Compressor will shut down at negative Four to protect itself it's one of the Protections that it offers because at Negative four you're in real danger of Going so low in the pressure category That you're going to end up damaging the Compressor because the pressure goes Down temperature goes down might be Slugging the compressor there's all Sorts of Hazards right there so you'll Switch to electric heat which is like we Talked about last time resistance heat Isn't very good as far as Energy Efficiency but also the good thing about It is it's simple and it doesn't depend On the outdoor temperature it's just Heating up the air as it passes across It there's no refrigerant flowing it's Just resistance heat so that's very very Nice in that regard it can be a Lifesaver in certain instances So let's hone in on the left side of the
Chart first on the left side of the Chart it has CFM so you can choose from 1020 1150 1350 is what we can see on the Screen now we're going to go to the very Top just keep a simple at a thousand Twenty And we see different temperatures indoor Dryable ranging from 60 to 80. we're Gonna go with 70 because that's right in The middle that's where usually people Keep their temperature in the winter Time so at 70 we'll see next to that is A TC that is total capacity so total Capacity at 70 72 degrees outside 70 degrees inside it Says 31.7 31 700 is how I've deciphered It after looking through this chart it Seems to be that is 31 700 they're just Writing 31.7 So at 72 like we talked about in the Previous video you're not doing a whole Lot of heating at 72. so let's go over To 47. 47 was mentioned in the previous Manual we talked about on the last Podcast so at 47 at 70 degrees 31.2 So almost the exact same as our 31.7 Total capacity we had at 72. all right That's a good sign it's not trailing off Already So let's slide to the right a little bit If we go down to 17 Our total capacity is 27.5 So that's a vast improvement over the
Single stage unit that doesn't have the Variable speed compressor that the Bosch Has it's sustained a relatively high Capacity even at 17 degrees and even as We go all the way over to negative 4 Degrees We are still at 20.7 remember that I Believe it was at zero The single stage heat pump I was looking At which was a Goodman was at 9 000 BTUs It was one quarter of the capacity that It would start out as if we're talking About a nominal capacity of 36 000 BTUs So that's substantially improved over a Single stage heat pump now what exactly Does that mean If I'm just an average Joe schmoe Technician which is what I really was I would think hey this is going to be a Lot more heating before you get to that Emergency heat meaning we're not going To have to have the emergency heat Running as often so we're going to save A lot of money that's one thing I would Consider I would also consider that we Will be warmer than we would when the Emergency Heats not running because if It is 9000 BTUs like the single stage Unit we still have the same CFM so I say A thousand CFM is blowing across 9 000 Available BTUs that air is going to be a Lot cooler than if it's blowing across 21 000 BTUs it's going to make the world Of difference we all have heard
Customers that have heat pumps for the First time we had this a very common Event where I live I'm in coastal North Carolina we're right on the beach we Would have Northern transfers that would Come from up North they'd retire and Come down to the beach we have several Very nice beaches we're like we're not Florida caliber but we're pretty good we Have ridesville Beach we have the Crystal Coast we have very nice beaches Down here shout out to Homer Homer Blackburn our Northern friends come down Here after having fossil fuel burning Appliances that are 130 140 degree Supply temperatures they come down here And just imagine them on a cold night Feeling that very very lukewarm lukewarm Is Almost too warm for how it feels it Feels like a cold draft is what it feels Like and this is the reason why when you Get to those cold temperatures The machine is trying to take the Available heat outside which believe it Or not is plentiful it's just not Designed for taking the available Heat At zero as well as it can take it from 17 or 47. Keeping in mind that there's a ton of Heat outside even when it's below zero Because the temperature scale goes way Down below zero so there's heat in the Air
But like we talked about last time Machines are designed for a certain Condition If you design for 47 and 17 Then 0 and -20 You're not going to be able to design For that you're not going to have a Range that's effective that large now That being said look at our variable Speed unit it's our best shot at Achieving comfort in all ranges So the Bosch looks like you are good all The way down below zero And almost have two tons of heating at Your disposal So I thought that was a great comment Way to bring that up and I'm glad we Could discuss it here on the show Because it's something that we need to Know if we are if you're selling Variable speed I mean that's a good Point about it you can mention that to Your customers say hey this is you know This is Zach on the television told me That variable speed was better for Heating so you should buy this it'll be Twelve thousand dollars and you can send Me like a chunk of that and I'll spend It on uh Power Tools Thank you I need a planer so I would Like a a bench top planer please That's how you reward me so I hope that Answered some questions guys especially Guys that are new to heat pumps and want
To learn more about their operating Capabilities variable speed looks like It beats single speed Probably could have guessed that but Seeing it in writing definitely sheds a Lot of light on it
