You are great! Very clear and sound.THANK YOU!

I watched this again because it’s brilliant. So easy to follow. Even for people like me. Thanks Derek Asian Jon. Training.

These training videos help so much and give you a much better understanding than just going through the books only 👍🏻

Hey Derek, genuinely thankfully for these. I've got my ACS in a few weeks and these are helping greatly with my preparation. I'm in for 2 days training before hand, but reading books can be very dull. Just a comment you probably won't even see as it's an old video. Just thought I'd let you know your work is really appreciated by us engineers. 🙏

I'm in training at the moment and I struggled with the vent in series your videos are really helping so thanks

Precise and clear explanation. I wish tutorials like this were about when I 1st sat my Acs. Flueing and ventilation was a pretty heavy subject as was pipe sizing 👌. The more you practice the easier it becomes. Like learning how to ride a bike, 2nd. nature. Plenty heating engineers use apps or vent calculation gauges now. 👍

Absolutely amazing! 🤩

Derek thank you very much for taking time to make this video for us. I was doing ventilation yesterday and could not get my head around it but after watching your amazing video i have a better understanging now you made it look so simple . I can not thank you egnough for your efforts 👍your a champian mate dnt let tail bearers put you down they are selfish people who dont want people to learn once again thank you sir👍.

Well explained good refresher 👏🏿👏🏿👏🏿👏🏿

Great video, moving through them slowly. Clear and well explained, so helpful, thanks!

Got my ACS reassessment in a month and I found your video extremely thorough and helpful.Carry on.Well done

Excellent much easier to watch your videos than trolling through technical manuals. This subject is less relevant than it used to be with less open flues about so its good to get a refresher with an inspection looming.

Good job! Nice tutorial!

god bless you Derek robins 👏💙👏❤️ I learnt a lot

Excellent video Derek. 😊

Derek you are the best teacher anyone can come across i am very lucky to come across your video i was in the middle of my gas training and i was so confuse and i almost gave up from continuing the training and i told my centre i dont want to continue with gas rather i want to plumbing instead but they refuse and i had to continue with very little courage on the training but watching your video for the first time has restored my confidence as every thing is very clear with your explanation. Bless u man

Good tutorial as usual Derek thanks 👍

Thank you for your help your video was very helpful! but on the example you gave us for the open flu cross boiler 30kw, the calculation doesn't seem right because 20.02 x 5= 100.13

THANK YOU. very very helpful!!! you are not only a professional gas engineer , but you are also a good teacher who make me understand unclear things i had...lucky to watch the videos free of charge

Thank you very much for these videos Derek. I'm filling out home work book and your videos are so helpful no rather copy but to learn and take in important information. Definitely would recommend TOMKAT GAS for new enteraces. 😁

Nice and simple explanations. Thanks Derek 👍🏻 Asian Jon. Training

A very good explanation for new beginners into the gas industry and also for experienced operatives who work on gas.

Once again a fantastic video...cheers fella.

Great video, very useful information and very helpful for us new trainees. Tomkat gas trainee.

Another well presented video with valuable and well explained information, always enjoy watching these videos as helps us to gain more knowledge through your explanation rather than reading and trying to understand it in the book, your explanation is much more understandable.. 👍👍😁😁

Unfortunately the math is incorrect.... 20.02 x 5 = 100.10

Great stuff for helping me with my revision. Mo

Hi Derek I’ve noticed at 15 minutes when explaining open flue ventilation in a room , your final calculations are( 135 cm free area ) you didn’t take off the 7kw adventatious air! Shouldn’t it be 100.13 cm squared Love your dedication to educate new & old timers like me. very clear explanation of the regulations and why there implemented. All the best Rob👍🏻

Thanks Derek. I am currently doing ACS course and your videos are brilliant and clearly explained. Thank you so much. Keep up the good work.

This video is really helpful to clear concepts

Derek watched all ure videos and what a help it was for my acs re assessment which I passed last week keep up the good work 👍

Evergreen presentation.... well-done Mate

These videos are helping so much. Using them to try and get ahead for my classes. Just need to find an engineer in my area. Looking for anyone in the Edinburgh area who are willing to to take me out.

brilliant guidance, so important to know basic when goling to look a gas appliance

Great tutorial, very well explained!👍Abdi

Great vid for revision Kamal Training 👍

A big thank you to you once again.

Great help derek just revising for my acs next week and was struggling remembering the ventilation calcs and room vent sizes etc keep up the good work 👍

Very informative video, keep up the good work 👍🏽

👍 👍 another brilliant video

Great video thank you for sharing your experience Bro

Mohammed Nazir. Excellence video.

What a great explanation! Look forward to every Wednesday. Will you do any videos on gas controls or going through filling out documentation on a job for example a service or landlord safety certificates. It's one thing being good at your job but to be able to pass that information on to other people in an easy to understand way is extremely difficult. Please keep up the great work.

Fantastic thanks Derick doing my re sit at M65 (company's choice not mine) your explanation is far easier and less confusing keep the great videos coming 😎

First class Video ☝️👍Connor

brilliant, I would have love to renew my ACS with you guys, unfortunately live nearly 300 miles away.

Very useful video. Thanks Derek. Polish Peter - trainee at TomKat😀

Really helpful video, thank you

This video is wicked, thank you

Great video. Very helpful to understand why you would require an outside vent. Whilst it’s important to understand the figures, I’m assuming in 2021, most people will be looking to purchase an appliance that does not require an external vent, especially in Winer!

Very very useful tutorial video for new gas students. Thank you very much sir.

Thank you Derek 😊

Hi Bro you explain everything proper way and nicely, Many of the instructors out their don't explain the hole Sanario like in this video you explain number 5 where it's coming from . Thanks Bro for further training I will definitely contact you.

Thanks for this found very helpful 👍

Very well explained 👏

Thank you bast teacher ever 🎉🎉

P.E.R.F.E.C.T ...Thank you a lot !!!

Many thanks derek I think I need to watch this every week to keep up to scratch with it also never use your phone as it can and does mess up calculations

“I might be wrong... but I doubt it” 😂

Thanks Derek 🙏 Benny

Thank you for the efforts, Allah bless you

Brilliant example 👏

Thank you Derek

Very informative 👍

I think I'll resit the ventilation exam tomorrow Derrick haha!

Thank you Derek, Mohamed Hassan

Great Education

Super excellent 10 out of 10

Brilliant 👍👍

These are great videos. With ducts though what are the rules/regulations regarding gas pipe work run in ducts?

Thanks Derek..

Pot on explenation mate thanks 👍

Ray Hurrell fantastic

Top vid.. helps a lot 👍

thanks Derek . Ion Vitiu (Nick)

i think the 1st calculation was wrong but I know you did it to check we are watching, well done, enthrawling, cant stop watching, great teacher.

Excellent u should make videos about chimney

Useful vid.

👍 Well explained

thanks mate do you ever link the documentation you use in the videos? stuff like the classifications could be helpful.cheers again

Excellent. Very well explained, clear and precise. Only 3 1/2 stars because that music is very irritating, and makes it difficult to concentrate on what you are saying.

very informative

Please don’t remove sir It’s 1000% is best explanation it’s really helping me sir Many thanks

Nice video but just one thing, you state 30kw but the data badge says 23.45 where you getting 30 from?

If your coming into the industry now, open flue appliances with vents are going to be few and far between. The last one I attended was about 4 years ago, In my experience its the cause of the most amount of friction with customers. The one I mentioned was a Baxi Boston boiler installed in a kitchen with no air vent fitted. The customer just about threw me out of the house after saying I didn’t know what I was talking about after I advised him it was unsafe to use the boiler. On another occasion with another customer, I got into another argument after a kitchen fitter had fitted a new kitchen, removing the air vent that had been fitted for the boiler and then boxing the boiler in tightly without any compartment ventilation. The boiler in question was an open flue Glowworm Hideaway. In many respects I don’t miss them.

You mentioned if appliance does not specify if it is gross or net, to take it as Gross, problem we have here is, it means you will make it even smaller by dividing the gross by 1.11. So we should assume its Net not gross. Am i right???

Very helpful and made it easy to understand, but not sure how the calculation on the first example added up. Open flue ventilation. The 20.02 x 5= 100.13. On your example it added up to 135.13cm2. Which ones correct please. Keep up the good work as its very informative and helps with my training no end.

Hi How we ventilation on flueless tumber dryer.

When you were measuring the terracotta vent, which side do you measure with the ruler? I'm guessing the smallest holes you measure with a ruler

Hi many thank to your great work . some thing to explain : 30/1.11= 27.027 30 - 11%= 26.7 the number should be 1.11 and not 11% please check and correct . then 5 cm2 for every KW after the first 7KW ??? so if we have 9 KW 9 - 7 = 2 * 5 = 10cm2 ????? please correct me . great respect Thank you

Hi Derek, Why should we duct a cavity wall to join an inner and outer vent? Thank you

You need to do one chimney systems

thank you DEREK

Davison here..thanks for this video

Thank you sir.🙏

Watched again 😀😀😀

Top man

Hey , I like your videos but how is 20.02 x 5 =135.13 ? Ain't it 100.1 ??? 27x5 would be 135 is in it ?

Derek how long to do a cesp1 course and do you do

15.02 minutes , 20.02× 5 should be 100 cm2 vent