Flue Gas Heat Recovery Explained | NGCFE National Gas Centre for Excellence

[@AllenHart999]

ngcfe.co.uk/

[@sergiofernandez3725]

Allen you would be great as a teacher. Taught me loads from your videos

[@AllenHart999]

That is very kind of you, Do you have any ideas for any new videos? Thanks.

[@sergiofernandez3725]

@@AllenHart999Electrical safe isolation would be good. Use off a lock off at fuse board. Use of clamp meter on tails. Seems people are getting shocks from the earth bonding reverse feeding

[@ivangoodall1]

Allen, thank you very much...that was just perfect. When you see Michael can you please thank him too and thank him for his time too. Can I also say that I have had many teachers in my life and wish they would have all been like you. Dyslexia or no dislexia you are one of the most easily understood, informative and inspirational people that I have had the pleasure of learning from, plus you would make an exceptional teacher/trainer. Thanks once again gents and take care 🙂

[@AllenHart999]

Very happy to help. If you would like any other videos just ask. Thanks.

[@manoszotos]

In usually shiny Greece we make the same principal with the solar panel boiler even when its cloudy day the water came 10 degrees higher. When its shiny the boiler doesn't work at all. We put a thermostatic triode valve before the cold feed. Nice video once again

[@Crimson_Blade858]

I enjoy watching your videos mate and I think that insulating that hot pipe back into boiler is a good idea and would definitely maintain that increase in temperature. Respect to you for helping us out 👍

[@johnburns4017]

Yes Allan, a short length or Armaflex lagging should be fitted inside the unit if it does not come that way. Air coming in at 1C can really cool the preheated water down.

[@thomaslpg2]

​ Have a good afternoon sir .....from Greece.

[@AllenHart999]

Thank you for watching.

[@lukeclarke1743]

Brilliant version demo 👍

[@nickcannon5592]

On the old boilers when flue gasses were 3 times ish hotter then may be, but 200 quid for 2 or 3 degrees I don't think so, very few customers would wear it. However love watching your videos mate

[@BogdanDumiter]

The more heat exchange surface there is in the heat exchanger, both primary and secondary, the better efficiency a product brings. Of course the use of high quality steel or very good heat transfering materials is a must in these applications to handle very frequent and rapid temperature changes.

[@fredjennings9268]

Thanks for the informative video, makes sense to lag the pipe.👍

[@AllenHart999]

I really like the idea of taking as much heat from the flue as possible. Thanks.

[@johnburns4017]

@@AllenHart999 I was thinking that if there was insulation on that return pipe, it would need to be fireproof as it is in the flue stream that is why maybe none is there. OK on the air side which is pedantic.

[@johnburns4017]

I recall many moons ago I used one of these stand alone flue heat recovery units on a warm air system. Warm air systems work on higher temperaures to heat the air so it does not come out as a coolish draft. A Multicalor warm air unit was fitted. (excellent product) This had only a fan, filter and copper heat exchanger coil inside, wity the heat exchanger heated by the boiler. All the boiler did was heat the copper coil in the Multicalor. One of these heat recovery units was fitted on the flue of the condensing boiler. A small cooper coil heat exchanger was fitted in the inlet ductwork of the Multicalor. A J&S elecrostic air filter was also in the ductwork. A pump, pumped water slow around a loop from the heat recovery unit and in-duct copper preheat heat exchanger. So the system had two coiled water-to-air heat exchangers, one being a pre-heat. Worked well.

[@Pete-wh2rl]

Hi mate. Just saw this, Great video and easy to understand the way you explained. Just thinking about the lagging, did think lag all the pipelines, inside the unit and outside too. That way reduce heat lost as much as you can, especially right now with all costs 😞.

[@0808-w9q]

Great video as always Allan , I’m a trainee and find these videos really helpful. Hope you are keeping well mate 👍🏻

[@mihaiachim5299]

8:30 I agree; maybe i will try to build one in the future for testing.... this thought has been haunting me for some years :D

[@johnburns4017]

The Intergas Xtreme combi has one coming integrated into the boiler casing as a part of the combi, flue gas heat recovery. Some ATAG models do as well and have done for a _long time._

[@AllenHart999]

Hi John. What’s your opinion on flue gas heat recovery? Have you installed any? Thanks.

[@johnburns4017]

@@AllenHart999 As energy prices have gone through the roof, these days I advise people to have a combi with an integrated heat recovery unit inside. Few ever took them up, but now they may. They need figures, like it will pay for itself in two years, etc. I have never had feedback on how much it has saved. Because, there was no before and after figures.

[@davep4703]

So Allen, the heat recovery unit is solely for combi boilers, only I always believed moden heat only could also benefit from recovering lost flue eneigy. Regards Dave Porter

[@jockster5525]

Great work guys . many thanks for your efforts ❤️

[@AllenHart999]

Our pleasure!

[@nigelcobb2959]

Hiya. Very educational and well explained, thank you. I have one question for you. We have a Gazco Riva2 500 running on LPG, 5.6kw output with a balanced flue (which could be extended.) It is basically a remote controlled gas fire. There is plenty of room in the 1 metre thick cobb walls to install the heat exchanger onto the flue before it goes outside. Can the system you are talking about be used to disperse hot air, and not water, from the flue and then piped it into the loft (single storey) and fed into another room? My brain is telling me this must be possible somehow

[@marcush6139]

Allan, I know your struggle I'm a new engineer and I'm dyslexic and I struggle with reading, writing, maths . And you videos, aswell as other engineers are a god send .. Question, when it comes to maintenance is it easy to strip and flush out

[@AllenHart999]

I have never known of any maintenance for the FGHR units. I would need to check. Thanks

[@jorgeysmith5118]

Hi Allan great video I enjoy watching them, wondering if you got any apprentices going around I'm doing plumbing at the moment at college

[@bazcambs451]

Any chance of a Intergas strip down. These boilers have 2 in 1 heat exchanger is the this more efficient than the usual 2 heat exchangers?

[@LeonWakelin]

What would happen if you piped the heat recovery uh it up wrong/backwards, would that cause you to have no hot water or would it just be working in reverse?

[@imranmajid1978]

This seems like the central heating condensation (condensing boiler) equivalent to hot water!

[@Pikachu777_]

Do you have to take that apart to inspect the flue on a service? Thanks

[@MatthewEng2593]

So what temperature should the flue gas be when all the condensate has come out?

[@joemartin3410]

Great video Allen as always I find them so helpful, I really like the flue gas recovery systems they work well I’ve fitted a few of the Alpha flow smart systems in HMO’s supplying 4 bathrooms and they work a treat, I would love the set up you have at home but don’t have the budget really for it right now as doing the rest of the my house up however I do need a new boiler so and been looking at the Viessmann 111 to make use of their new smart controls do you know if Viessmann allow other flue recovery systems to be used as I don’t think they make one?

[@haroldwebster1459]

Can this idea work on a combi condensing boiler, because I thought that the exhaust gases already had had their waste heat returned to the incoming central heating system water

[@AllenHart999]

Yes, These are condensing boilers. Thanks.

[@rickysheldon4355]

❤️ your videos 😄

[@Memories4lifemedia]

Great vid can you do one for Baxi pls pls

[@richardkingadi5511]

If they're as efficient as Baxi claim, it seems almost criminal they aren't installed as standard on every boiler! I wonder how they get way with it....? I#ll bet they are a very expensive retro fit too!

[@scoobydo2]

Does or can this work with a condensing boiler?

[@AllenHart999]

yes

[@matttate9155]

Nice

[@poorfordtransitowner1627]

Are these worth it mate?

[@AllenHart999]

It’s built into the Atag boiler and they really do work well. Thanks.

[@poorfordtransitowner1627]

@@AllenHart999 so instead of the cold main going into the boiler it goes into the cold feed of the frs an the hot out goes into the cold feed on the boiler?. Seems like a good idea

[@AllenHart999]

@@poorfordtransitowner1627 it just preheats it. That way it all works better.

[@johnburns4017]

If you use a lot of DHW, and with gas prices doubing in price, these now make economic sense. Previously it was diifficult to justify them.

[@AllenHart999]

They should just be built in as standard tbh. Thanks.

[@johnburns4017]

@@AllenHart999 That may be the case as gas prices rise.

[@saumabhamandal8778]

Nice video, but try to avoid repetitions and keep it under 10 min

[@nickirlam4811]

👍

[@GripK]

А у Вас в стране напольных котлов не существует? Don't you have floor Gas Heat in your country?