Shortcut to HEATING GENIUS! Mass flow rate

THE HOLY GRAIL OF HEATING. Mass flow rate. A MUST for all heating engineers!
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[@HeatGeek]

Anything that wasn't explained well enough?

[@1991elliot]

Only thing is you jumped from talking about mass flows to volumetric flows without mentioning density (upon which volumetric flow is dependent) and the units of the equation are in mass terms, so a density term has to be included if working in volume flows (or state assumption that water is 1000kg/m3 density).

[@HeatGeek]

@@1991elliot absolutely correct thanks for pointing out. We use the terms and conversions so interchangeably that this is easily missed out. Thanks for pointing out!!

[@1991elliot]

@@HeatGeek Keep up the good work. A lot of Engineers struggle to communicate well so you’re doing a great job!

[@HeatGeek]

@@1991elliot thanks mate!

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@lewiskirton6497]

Great and inspiring lessons here. Keep them coming please!

[@antonycollis5284]

Great video, thank you for explaining and going through it.

[@HeatGeek]

no probs!

[@paullenton2076]

Very good video, was due to go on one of Marice’s courses last year when I was in the uk. Course got canceled. Will get on one when we can travel safely again

[@simonexcell6496]

Thanks Adam Enlightening. Top man

[@M.Begley]

That triangle just changed the game ! Thanks Adam! 😁❤️

[@HeatGeek]

boom!

[@davidprior1182]

Awesome Video Mate. If only there were more videos like this. Currently in my final year of HNC Building Services.

[@henrybartlett1986]

Excellent. Thanks for this.

[@HeatGeek]

No probs

[@JordanPhillipsScovell]

Top man, cheers Adam for the simplicity. I was having a hard time getting my head round it😅

[@kosalaperera1899]

Should call you "Heat God" mate. Great stuff. Thank you Sir.

[@JadenRoseGuitars]

Nice vids Adam, well presented and informative mate.

[@HeatGeek]

cheers matey

[@TheDickPuller]

Thanks, very clean explanation. Your videos are very insightful, please keep them coming👍

[@HeatGeek]

Thankyou!

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@b-techheatingltd6690]

Nice work guys 👍🏻

[@HeatGeek]

thanks!

[@warrenandrew69]

Great video very informative

[@HeatGeek]

Thanks Andrew!

[@roberthuntley1090]

One rule of thumb that I stumbled across on a plumbing forum is 'one kWh will raise the temperature of a tonne of water by one degree C'. From memory its only 92% accurate, but it provided a nice, simple, initial assessment to put you in the right ball park before getting the calculator out.

[@Jammydodgers41]

Studying for level 2 plumbing then hopefully looking at becoming a gas and heating engineer. This was very helpful and easy to understand. Thanks Adam.

[@HeatGeek]

good stuff!

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@KrisFarquharPlumbingnHeating]

Brilliant. I purchased the cibse heating design book in 2014 . But for me watching your 10minute explanation video sinks into my head far far better than reading . But ill go back to the book combined with learning from your excellent teaching skills . Thank you for your time taken. Kris

[@HeatGeek]

Thanks!!

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@garethurford]

Great video, thank you. Need to watch it another few times though 🤯

[@HeatGeek]

yes, keep watching all of them and more will sink in each time!

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@ori4640]

Thanks for the video, specific heat of ethylene glycol is less compared to water so you will need more flow rate from the pump, also the number of 84 is not saint, on some systems, you will need to calculate a different delta T, so you can use the formula q=mc∆t to know how much energy you need (gallons of water inside the water tank) and than you will need to calculate what the house/facility heat loss, and than you will need to calculate how much heat (Q) you need from the system and how much flow rate from the pump to transfer. good luck. 👍

[@maxk8396]

Brilliant Adz Max

[@HeatGeek]

thanks bud

[@tonycy510]

I remember Morris Mud from when he taught Plumbing at Lancaster and Morecambe college, he was a very knowledgeable chap and very good at passing that knowledge on in understandable terms.

[@stevieh2501]

Finally an enjoyable math lesson.! I'm learning Alot thanks.

[@HeatGeek]

Great to hear Stevie, thanks 👍

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@ScottyDog345]

Constants.Nice

[@hammettblasterryan5499]

Can you do a heat pump mass flow, and a lot more online videos of heat pump related stuff.

[@Airwiseheat]

Hi Adam, does this calculation work in respect of underfloor heating circuits? Or how would you calculate a circuits required flow rate? Many thanks

[@ogfeen]

How do you work out the system resistance?;

[@quattroman-fc4sd]

Do you have any content on solid fuel stoves mixed with oil boilers ect? Great videos👌🏻🛠

[@HeatGeek]

No sorry but. Unlikely too as they're both dying out

[@sevastoskoumtzis5401]

I have a 3 floor house 170m2 with underfloor heating , the lowest power of my combi boiler is 5.7 kW. As e result , when one of the zones is active , it takes about 30mins for the boiler to warmup the system and then it overheats and cycles ! Is there a way to dump some of the extra heat to the other zones by partially activating them? All zones are controlled by simple on/off programmable thermostats .

[@AllanHundeboll]

Hey. My heat pump installer left without tuning the installation, and ignore my emails. So your videos are much appreciated. The manual for my heatpump say only limit the pumps flowrate if the flow is to noisy. But if i don't limit max flow it seems to pump to fast and delta T drops to 2-3 °C. Some sources clams air to water heatpumps optimal delta T is 5°C other claims 8°C and some say flowrate should be 2, 2½ or 3 times energy output (eg 5KW = 10-15 L/min ) So what pump speed should i target with heatpump and underfloor heating?

[@optionenergysolutionsltd6611]

Great stuff. 1 tee please 😃

[@HeatGeek]

Tees coming soon!

[@SME_Ste]

As a non heating specific trade, this is very interesting to watch. Would these calculations apply for a boiler pump on a system boiler that is of the modulating type?

[@HeatGeek]

Mass flow rate law always applies. Its a physics law

[@Kingkongkirk1234]

Am I right in saying if I had 20kw of radiators on 22mm pipework and the flow and return was 10 degrees then the flow rate would be 0.47l/s, but 22mm can take a maximum of 0.35 l/s so it wouldn’t be possible to get 20kw through the pipe to the radiators therefore the last ones on the system would be struggling?

[@rosstaylor4924]

Another great video👍 when’s dose the course start?

[@HeatGeek]

Thanks. Towards the end of the year.

[@rosstaylor4924]

Ta 👍 looking forward to it

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@sbplumbing3905]

Great video, but how do you go about calculating pressure losses in a system.

[@HeatGeek]

Video to come on that one...

[@pod990]

This is great, have you considered making some working examples and work sheets or will this be on the course?

[@HeatGeek]

Not only will the be on the course but in MUCH more detail

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@conand1413]

Great Videos with a good scientific and math approach Is there any books that you recommend? Or have you considered doing one urself Many thanks

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@mrsam8250]

Hi Adam, fantastic video as usual! Just one question. Am I right in thinking that a Delta T of 20 with a MWT of 60 will output more Kw than a Delta T of 20 with a MWT of 50? If so would that need to factored in?

[@HeatGeek]

Yes thats right. But mwt doesn't not come i to this equation so its irrelevant

[@keithware5314]

Hi would you please tell me if thermodynamic hot water heating is any good. Thanks for your videos.

[@HeatGeek]

Hi. No. 👍

[@marka4706]

how do you find out system resistance of an existing system to size a pump correctly when you cannot see pipe runs. say for fixing with some rads that are not getting hot and you believe the pump to be wrong thanks

[@HeatGeek]

Unfortunately younneedbto pace out and estimate

[@mgbroadsterJ]

How can you set the modulating pump to the correct litres a minute ? If you have radiators and underfloor heating controlled by a 2 motorised valves how can you have two pump speeds at the same time ?.

[@HeatGeek]

First question. You measure the DT and choose the setting closest to your dt or splash out on a dt pump. Second question depends on pipe work layout and if your talking about a system pump of boiler pump. Boiler pumps are burner linked so will automatically modulate to the correct speed to maintain a wider dt.. with system pumps the layout will help you decide between proportionate pressure and constant pressure... or you can use a dt pump again.

[@jonathanray6606]

Great video, if i was trying to work out a flow rate of an underfloor heating circuit, could I work out the room heat loss(in kW) and using the delta come up with the flow rate?

[@HeatGeek]

Yep.. kw of room ÷ 29 = flowrate in lps

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@mgbroadsterJ]

I noticed you had a buffer tank on one of your systems is it working like a low loss header ?

[@HeatGeek]

Ide need to know which system you were talking about?

[@seanmurray1734]

Great delivery..could you explain how to set a by-pass valve correctly. I just stick them on 2 , but I know I’m not doing it right... 👍

[@HeatGeek]

Bypasses dont relaly work with modulating pumps.. British standards is light years behind.. I'll try and include it somewhere thanks for commenting

[@seanmurray1734]

Heat Geek Haha.. I’ll stick with with 2 then... Nice one

[@HeatGeek]

@@seanmurray1734 may aswell stick it on max.. if it opens it causes the flow to bypass and warms your return water unnecessarily

[@seanmurray1734]

Heat Geek Righto. You’re a good egg. Much appreciated

[@HeatGeek]

I’ve just released a course detailing everything you need to know to become a heating genius! What’s more it’s been recognised by the UK government department BEIS which have offered to heavily subsidised the first 300 spaces! courses.heatgeek.com/

[@loneyscape4334]

hey! i am apprentice plumber in Australia where we are rather behind the rest of the world in this field, so here i am trying to better undertstand all of this! (before i eventually undergo one of your courses) if a greater delta t is better (within reason, we want everything circulating) would it not be better to lower pump speeds to increase the delta we get?

[@HeatGeek]

Yes, you want lower pump speeds to widen the delta buddy.

[@nickwinn7812]

A gerater delta t is not necessaraliy better. A greater delta t will give you a better heat transfer per unit area of your emitter or collector ( you haven't specified which you are talking about), but a delta t of 90 degrees k on a radiator would be dangerous.A condensing gas boiler usually has 2 heat exchangers, the primary is directly above the flame and will have a delta t of several hundred degrees K and then the secondary is further up the flue and will have a delta t of maybe100 degrees K ( I'll admit I'm guessing on that one). However the crucial tempemperature on the secondary is not the delta Ie the difference between the incoming water and flue gas temperature. but rather the temperature of the heat exchanger itself which must stay below 323 degrees K at sea level ( or thereabouts) in order for the superheated steam in the exhaust gasses to change phase and condense out as liquid water, thus liberating shed loads of "heat" energy into the circlating water of the heating system. The delta t across the boiler flow and return will affect how efficient that particular boiler is, because those crafty engineers will have combined all of the variables that they can control, into their control system to make the boiler work at it's optimum, but bear in mind ifg the return temperature is too high it will never "condense" and so forget efficiency. It is very important that you get the return temperature ( not the flow temperature) for your condensing boiler right in order to get max efficiency. After that your emitters (radiaters, underfloor heating etc) need to be matched in size tto the room thay are in to deliver the heat required for that room which will of course depend upon the delta t of each surface of that room and the u value of that surface and the area of that surface. If youv'e got this far You will probably make a great heating engineer, If not, tune into Roger Bisby and be a "has been"plumber.

[@pfischer4664]

At 1:05 ... Ooops "...the energy in..." in KW - I know you mean Power but a fundamental blooper that should be corrected :) Also at 8:36 "....generally if you've got a hot flow and hot return you've got a wide DT..." Nope!

[@user-sz4gh9cs5f]

I dam when u multiple(SHC) 4.2 AND DT 20 and get 84 has d anwers... what unit do that 84 represent???

[@HeatGeek]

Joules consumed per liter of water

[@handle1196]

How much more flow rate does ufh require compared to radiators? Whats the KW output based on for me to play around trying this formula? I have my room by room heat losses.

[@HeatGeek]

The kw is what ever you put in the box.. ufh is 3 x faster

[@handle1196]

@@HeatGeek i was just trying to figure out what kw i add to determine pipe sizes to my heating manifold and pipe sizes to the radiators, is it my house heat loss of 3.7kw, the ashp output of 7kw or the gas boiler 26kw. They say heat pumps requore a higher flow rate compared to a boiler, is this because of the heat pump or due to the low temperature flow, because we can now run low temps on a viessmann 200 too.

[@andystephenson8845]

Hi Trying to size a system boiler, I know the total heat loss for the whole house, the length of UFH pipe, the design flow rate, but how do i bring in HW supply to a UVC. if I run the UFH from a buffer how can I ensure condensing as presume the boiler will be controlled from a stat in buffer and a stat in UVC. Is there such a thing as a modulating cylinder stat? How do I sign up for you courses? thanks

[@HeatGeek]

Hi Andy.. the only way would be to weather compensate the buffer temperature.. anybquakity boiler will be able to fo this.. why are you using a buffer BTW? Course info coming within the next month or so!

[@andystephenson8845]

@@HeatGeek Hi Thanks for your reply, the buffer was to avoid boiler cycling, design flow temp for the ufh is 45deg. I also have 3 small rads and two towel rails on a manifold system on first floor. have three en suites and a house bathroom all with showers, one bath. It is a total renovation, all plumbing and boiler will be new. yet to buy a boiler and uvc . Came across OSO cylinder that is 360lts total, with a 100 buffer in the bottom, but coil is only 1.8m2 in upper tank. It has 3kw immersions, one in each tank. House has been first fixed for Heatmiser stats, but I don't like the idea of on/off stats. House is well insulated and will have mvhr. what would you recommend as a solution

[@HeatGeek]

​@@andystephenson8845 just buy a Viessmann 200 boiler as thats unlikely to cycle as it modulates to 1.6kw!. cycling losses are only around 1%, it think youd lose more efficiency from the buffer losses and mixing. the install will be half the price if you dont use a buffer. too

[@AwestruckChemicals]

Shouldn't Delta T be the difference between average temp in radiator and desired temp in room?

[@HeatGeek]

There are lots of dts. For mass flow rate its flow to return dt. The dt you refer to is the mw-at-dt. That bares no relevance to the required flow rate at all.

[@AwestruckChemicals]

@@HeatGeek Ah okay, I think i get it, thanks

[@garytango]

👍

[@peterlawton1842]

'Mass flow rate is simply Kg/s. You are referring to the particular value of this quantity which will produce a specific deltaT across your system. You should call this something different, for example 'desired mass flow rate'.

[@nickwinn7812]

Ok, it's late at night and I'm a bit tired and it's a while since I calculated any mass flow rates. After describing SHC very well, and explaining that SHC is the capacity of the medium to store energy per unit mass (kg), you only talk about volumetric flowrate (litres/sec) , without explaining how you got from kg to L/sec.. Ok, so, w're talking domestic heating systems here so, the medium (water) has a density of 1 (or thereabouts) and, crucially, doesn't change phase, and therefore 1 litre/sec = 1kg/sec( because 1litre of water = 1kg of water) ( or at least close enough to your margin of error for calculations to not really matter). I make this comment for 2 reasons only, The first being that this omission in the explanation might confuse some folks and the second being that in one of your discussions with that Bisby bloke you said to him something along the lines of "it's not about flow rate that's important, it's mass flow rate". Well, If we are talking water and no change of phase, flow rate (volumetric flow rate) and mass flow rate are interchanbeable. ie. if you are pushing 10litres /second around your system, you are pushing 10 kilogrammes/ second around your system. Luckily poor old Rogerer was too thick to pick you up on this point, but it did make me question do - you understand what you're talking about? I'm now going to qualify that by saying that I think you're doing a great job and thanks for that. Teaching thermodynamics, however, may not be your forte, so just be careful, it only takes one prat to spot an error and shout it out in an un-reasonable way to undermine an awful lot of your otherwise excellent hard work.

[@johnbunyan5834]

I have just started to subscribe, to this channel. First: You look much more credible with your cap on the right way round. Second : You have just watched and commented on Skill Builder and said that he was 'angry' , and mentioned heart attacks. Well , that is just his style so don't confuse it with anger; and if , sometimes , he does appear to veer off the main subject, look at the number of subscribers to his channel. Right. I shall follow your channel with interest.

[@cliveramsbotty6077]

delta t is greek

[@HeatGeek]

Correct. Difficult when off the cuff! My bad

[@prolarka]

Just write down the equation to start with.

[@SkillBuilder]

Delta is Greek

[@craigbanks9532]

No mention of mass flow rate so why describe the video as such??

[@patrickwheeler2646]

Literally one minute in, did you watch the video?

[@christinecameron7970]

Is there such a channel for electricians??

[@assimil8or]

That Delta is Greek, not Latin.

[@pinarellolimoncello]

Dear Heat Geek, I see you consider yourself a heating genius, good, am glad to hear it, could you please add the acronym RCC to your heating engineers tool box, it stands for Radiated, Convected Conducted, and is a very quick way for your customers / rest of the nation to get on top of heat loss before they all go broke from rising energy costs. They will have to do some of their own research as not possible to discuss all on here. Everyone is familiar with loft insulation , double glazing at great expense , prospect of flashy heat pump etc but what about the nitty gritty of windows that never got foamed up, howling drafts from badly installed windows /doors ie convected loss. What about cold north walls, radiated and conducted loss, what can be done about it. It has probably occurred to you but I'll mention it for benefit of everyone else , retro fitting under floor heating, very expensive/ disruptive for purpose of maximising efficiency of heat pumps, would it not be simpler to do it on certain walls in a house..yes there is the issue of putting screws in to the wall but with a bit of imagination and ingenuity that can easily be resolved. Thanks for uploading, is nice to see such professionalism.. Let there be light is what it says, and you're doing a good job of it , well done. Just subscribed . Ps Please dont fall out with my mate Roger, you, him, urban plumber are doing a much better job than anyone in Parliament that is for sure. The goal should be , best of both worlds, Warm houses/ low bills, I walk the talk, have a warm flat that runs on vapours and is still room for loads of improvements, wait till I get the 500 mm celotex out