How a Condensing Boiler Works

[@seattlebest79]

Direct to the point explanation of condensing boiler. Thank you for your video and input.

[@MEPAcademy]

You are welcome!

[@scottwilson8880]

One of the best I’ve watched thanks from the wetlands of Scotland :)) I’ve now adjusted my pump down from 2 to 1 to get in that return colder sweet spot . Top video Albert Einstein once said the definition of a true expert is to be able to explain things in simple terms .

[@MEPAcademy]

Glad it helped

[@GB19751]

Good theory explanation. Here in Europe we have metric so I don't understand US temp measurements so cant relate to what is cold .

[@GB19751]

Do you want join EU?

[@MEPAcademy]

Sorry Graham, but we are starting to incorporate metric in future videos.

[@ponchow6618]

Explained nice and clear. Thank you.

[@MEPAcademy]

Glad it was helpful!

[@julianhowarth1075]

So essentially a condensing boiler harnesses the waste exhaust heat to preheat the incoming cold water. This results in less energy needed to heat the water to any given temperature. This process results in condensation (condensate) water, and its disposal ?. 1, Why is the condensate water considered acidic by this process ?. 2, How does a non condensing boiler deal with condensate water which is not captured and disposed of, albeit less efficient ?.

[@MEPAcademy]

1) The PH level of the condensate is on the acidic side so it needs to be treated. 2) A Non-condensing boiler should not have any condensation with proper design. If the non-condensing boiler has condensate then it will corrode the heat exchanger, which does happen.

[@Stealfos]

The condensate is acidic because of a chemical reaction by the heat of the gas burned.

[@nickhickson8738]

Combustion products of burning gas I suppose. CO2 dissolved in water forming Carbonic Acid is acidic.

[@fixingtrash2458]

1. This is a pretty poor explanation as to why it is acidic. Condensate from cooling coils are not acidic, so why is it with boilers is the original question. 2. Again, not answering the original question. You just say it doesn't have condensate, not why it doesn't have condensate.

[@Jimbo878]

is carbon monoxide present in the condensation outflow pipe?

[@MEPAcademy]

Small amounts of carbon monoxide are exhausted, while the condensate is acidic and should be treated before being sent to the drain.

[@Jimbo878]

@@MEPAcademy appreciate your reply

[@Dicofol1]

I didn't understand the latent heat section, can you elaborate more ? Is the 970 Btu/Lb universal or only for Natural Gas fuel burners ?

[@MEPAcademy]

That's the latent heat of evaporation for water, which is universal. See our video on What a BTU is, that will make it clear as to where the 970 Btu/lb comes from.

[@SayWhaaaaaaaaaaaaaaaaaaaaaaat]

Usually condensing boilers is efficient at about 85% AT BEST. All boilers is configured in such way that they are NOT efficient. Also lot of people uses them inefficient. To get efficiency you MUST not exceed flow temp of 50c. and as much cold return flow as possible. There should NOT be visible 'smoke' coming from flue. MOST people think if they see 'smoke' (it's just water vapor) coming from flue it means it's in condensing mode. it's INCORRECT. If you see white 'smoke' coming from flue this means you are NOT getting high efficiency your condensation happens OUTSIDE the boiler, because it jut too hot inside to create droplets. Most people uses condensing boilers at VERY high setting like 60c flow temp at which no condensation is happening and boiler efficiency is the same as standard boiler's. You have to use as low temp as possible to get NEAR the specified efficiency. Your video also have this problem you only talk about RETURN flow temp, while flow temp is important too. The higher flow temp -the less surface of cold area the less condensate. So flow temp is as much important as return temp. Also most important efficiency requirement is - outside temp sensor attached to boiler and the best would be to have room thermostat too, so boiler could use both data and choose optimal flow temp.

[@MEPAcademy]

Thanks for the comment.

[@leonperry123]

Need a video on how to actually reduce the return temperature.

[@MEPAcademy]

Thanks for the suggestion.

[@adobo6905]

You need to redesign or modify your existing heating coils/ radiators (add more heat ejection surface)

[@MEPAcademy]

@@adobo6905 Thanks for the suggestion.

[@SayWhaaaaaaaaaaaaaaaaaaaaaaat]

It's VERY easy. the slower the pump -the colder return. so just reduce the pump speed. Also flow temp is as much important as a return. Because of the higher the flow temp -the less cold area the more heated area the colder return have to be to create condensate. This video bit misleading because boilers have water in coils, it's much less area than in this video. So heat spreads a lot to a colder area too, leaving tiny area to condensate to.

[@SeosamhMacUaid]

@@SayWhaaaaaaaaaaaaaaaaaaaaaaat what is the idea return temperature?

[@johnf3326]

So why does my condensing boiler flue 'plume' even with flow temp set to 50c?

[@MEPAcademy]

John its best to have an experienced boiler technician look for the reason as it's not easily diagnosed from your description. Was this during a high relative humidity day? Is the forced draft fan spinning faster than it should, blowing out the condensate instead of it draining? Is the drain line clogged? There are many things to look at, and anytime there is a burning fuel involved it needs the attention of an experienced technician.

[@fionnan2811happy]

It might have to be flow speed adjusted to get the 22°c between the flow and return

[@Iama_Gem]

Thank you❤

[@MEPAcademy]

You're welcome 😊

[@pouyasoheili6703]

👌👌😍😍

[@MEPAcademy]

Thanks for watching.

[@Cagstok]

why is he talking like that. unlistenable.

[@MEPAcademy]

Sorry, but the Engineer was born with that voice.

[@jibjibam]

İt is very well listenable, especially for non-native speakers.