Jamie, you are the hero! I fixed our Boiler by following your instructions and got HOT WATER!!!! Now we can take a bath!! Thank you so much for this very INFORMATIVE VIDEO!!!
My home has a hot water storage tank and I have been running the boiler stat at 65c. A year on and the gas usage like for like is a third of what it was when we first moved in with the boiler set at max 85c. Saving £500+ a year now!! We have also had the noisy old pump replaced with a new smart variable speed pump. With current energy prices having your heating controls set optimally for efficiency and comfort can save you £100 or £1000s
Condensing mode starts at a return water temp of 55c. Then it is a gradient… the cooler the return the more efficient and more condensing it is doing. Heat Geek also did a video on this, you want that water in your rads as cool as possible to keep the house warm.
That is correct. The reason for the recommendation of 55 degrees is so that the heat being emitted the radiators during warmer months is a much nicer temperature. Otherwise the heat curve of the property will all over the place.
I have a Vaillant condensing boiler, radiators, external temperature sensor. The house is well insulated too.. But whatever heat curve I sett the radiator water goes always over 50-55 Is there a way to limit the temperature? I don't expect negative 20c° outside.. The curve is now at 0.90.. Can I sett something beside the heating curve? I've watched this one, but it's for vitodens ua-cam.com/video/tK38GyHTsbY/v-deo.html
@@luckystrike656 yea on the Vaillant you can set a max flow temperature. You’ll need to go into the settings by following the procedure in the manual and from there you can set the max flow temp. I’ll be honest, I’m not on the tools any more so I can’t remember exactly how to do it for all boilers, but for different Vaillant’s there is a different procedure so make sure you read the book. Thanks
@@luckystrike656 you should be able to limit the maximum flow temperature in the settings. Sounds like your heat curve set too high or your weather comp ain't set up right.
The 55C rule for condensing is not the boiler temperature it is the return temperature from the radiators. As radiators should have a 13c to 20c temperature drop across them a boiler set to say 65c will still condense as the water entering the boiler should be around 45c to 50c.
This is all well and good if you have combi system, however like myself with a conventional system you may as well just leave the boiler near the max temperature because it will never condense in hot water mode which is used 100% of the time, even with the balancing valve on the coil throttled right down the return temperature will still very quickly exceed 55 degrees, so i don't see much point chasing slightly extra efficiency I'd much rather have faster hot water and heating times!
Hi NRG, there are controls available that allow the system to have 2 different temperature for heating and hot water. Heating will be set for condensing and hot water will be max for rapid re heat. It then only allows either heating or hot water to be used at separate times. But other than that your point is valid 😊
If you have a newer condensing boiler that has outside temp sensors try to utilize outdoor air setback. It will lower setpoint based on outdoor temperature. Have a professional make sure your boiler is setup right.
The bar isn’t as important for efficiency but a recommended range of between 1 and 1.5 when cold is good but not the end of the world if it goes slightly higher. For hot water it depends if you have a hot water tank or not. If you don’t then 50 degrees is a good temperature to aim for. Hope this helps 😊
thanks for the information.do you have any videos explaining the valves on the side of the radiators.i have a radiator in my bedroom that has two valves but no caps on them so i dont know what they do.if i turn one it makes the radiator boiling hot and turned off its off.i dont seem to be able to vary the temperature.
Surely if you have radiators a little oversized then the water flowing through does not need to be as hot. Problem today I see when new rads are fitted they go as small as possible the engineer not calculating rad sizes properly
Its the return temperature that matters, right? Above 55 does not condense but the lower the return temp the more efficiency. I tried setting the outlet to 45 but unfortunately the system struggles. With bigger rads this would work fine but its an expensive solution. I wish I had a system that modulates the boiler temperature according to outside temperatures
I think it's flow temperature that people are referring to here. And there shouldn't be a need to make such smaller adjustments normally - the boiler would just run longer when the outside temperature is lower, in order to reach the desired warmth (set by your thermostat). For instance set the boiler's flow temperature to 50 degrees C and forget it - if there is insufficient insulation in the property or the radiators are small etc then you can set flow to 55 and that should be it.
Get a thermostat with opentherm capacity (Honeywell Lyric does this) and make sure your boiler can do opentherm. It’s plug and play. I prefer opentherm to outside weather compensation.
My Potterton Promax He Store is at 45C, I tried 35C, but it complains and starts to sound like a T-Rex. I was trying to simulate an ASHP. So far 45C is fantastic with the outside temp between 2 to 6C and the thermostat set to 17C. My house glows with warmth, and it doesn't cycle a great deal. I have mine switch on at 2200 to 2400 and 0700 - 0900 (when am in) When I get home (2230)I turn on a fan heater and IR panel for my TV room, once it gets upto 18C (3 minutes) I turn them off and let the radiators take over. Seems comfy doing this. Hot water is set to 80ish C. Every now and again I will do a high temperature cycle. I don't want bugs in the water. They love it at these temps.
Will the app allow me to adjust the temperature of the boiler or can it only be controlled by a Gas Safe Engineer from the boiler itself? Also, I've heard that condensing mode is important to even system boilers as the heat exchanger will stay cleaner and the boiler will burn more efficiently. Why do you not suggest running the lower temp (with oversized rads) on system boilers as well?
What about the anti cycle time setting, surely this affects it? E.g. default on my WB is 5 minutes ( I think it's around 20 minutes on a Valliant) but it can go from 3 to 45 minutes. By using a lower flow and a higher anti cycle time (say 30 minutes) the usage on mine in -3 C conditions, flow 55C, anti cycle 30 minutes, got it up to 18C target temp. My question is, what is the usual ratio, low flow high anti cycle or higher flow (60 ish) and a lower anti cycle time?
Hi all. I have a Vaillant Ecotec Pure combi boiler 26.1 kW and I'm heating a 120 square meter home (9 radiators, the biggest one is 100x60 cm, 22). Is it OK if I set the flow temp at 65 Celsius? Outside is -1, 0 C and I cannot get 23 C in my home. So, if I ramp up the flow temp at 65 C will I lose the condensing efficiency? Thanks
No. Your system will lose at least 10c by the time water returns. Just make sure your rads are properly balanced. But set temp as low as possible for max efficiency
Does the 55 degree setting apply to both the heating and hot water? I have just had a combi installed and have the heating temp set at 65 degrees and the hot water at 45 degrees which I find ideal without having to mix cold water
Hi, Jamie here from the video. You can set your hot water on a combi boiler to whatever you want in my opinion. I always went 50 degrees. What it actually achieve will vary depending on the time of year too. Hope this helps
Thank you, Jamie. That was very interesting. I live in a two bedroom flat, with 5 radiators. I have a Glow Worm Betacom2 24 combi-condensing boiler. I also have the Tado Mulit-room Control, with Tado SRVs on each radiator. I have also balanced the radiators. My Question is: given that I need to keep the return temperature below 55C, what temperature should I set the boiler flow temperature to, in order to get the Tado system to operate efficiently, while also keeping the boiler operating in Condensing mode? The video on the British Gas website, advises to set the boiler temperature to the Maximum - even with a combi-boiler - which seems to contradict, that which you and other have said.
Well obviously you will be fine to set it at 55 for starters. If all your rads are balanced properly I would say that the heat loss from the rads would be 10c minimum, so setting the output at 65 should be fine. But if you are warm, the lower the better
It should be set at the minimum temperature needed to sufficiently heat up your property. The lower the better, if you'd like efficient heating in condensing combi boilers. The better your property is insulated, the lower your boiler's temperature can be. For example, if your flow temperature is set to 40 degrees C and you feel warm enough (i.e. your room or property doesn't lose heat faster than the radiators warm it up), then that's ideal.
In spring/autumn our rads are set to about 30-35c as it gets colder we can get away with 45c flow temp but now we have an opentherm thermostat which does it for us.
1) Does a modulating boiler only modulate down the burner, or does it also modulate the rad pump flow rate? 2) is the modulation power (kw) set by the opentherm stat or is the flow temp set by an opentherm stat and then the boiler chooses the appropriate kW? 3) if I use a weather compensating control like a google nest, does that automatically set the boiler output or does it set the flow temperature?
1. On some boilers depending on the version of opentherm they are working to, the opentherm can tell the boiler to modulate the pump at burner on/burner off. Our ideal Vogue runs the pump at high when the burner goes off and then modulates the pump lower when the burner is on. 2. The opentherm controller will tell the boiler what flow temperature it wants, the boiler then modulates via it’s internal safety circuits the burners to achieve that flow temp. 3. Weather compensation is different in that it utilises the outside air temperature and you set a linear heat curve e.g at 0c outside your flow temp would be 60c but at 15c outside your flow temp would be 25c. The thermostat will just tell the boiler what it wants and the boiler will adjust it’s output… I’ve tried both and I prefer opentherm as it’s based on the actual internal conditions the greater the diff between set point and actual temp the harder the boiler works.
Thanks for this - I have a condensing combi-boiler, but the heating dial only has numbers rather than temperatures - how do the numbers equate to temperature?
Hi I have a condensing boiler and radiators, and external sensor and calormatic control. Even if I read the outside temperature at 9C°, with a heating curve set to 0.90, the boiler is pushing the water over 50C° and my house goes over the sett 22C° Is there anything I can do to limit the radiator water temperature to max 55C°? A know it will not be negative 20C° outside.. I'm not in the NorthPole :)
Hi Jamie! I’ve never had radiators to heat any home I’ve lived in. I just had the logic combi c30 put in because I’ve never had to use radiators I’ve no idea is it safe to lower my radiators put the boiler at around 60 degrees? My main question is can I keep the boiler/ radiators running all day until it get to warm? I would really appreciate your help in regards to that. I’ve lived in hot country that never needed heating. Totally lost. Thanks🤯
Hey! I have same boiler, so yes you can! There is a school of thought that you lower the flow temperature of the heating system but leave it running longer... This is better for the system apparently because its not cycling on and off and also can save gas because its not having to do regular blasts of heat. Or something 😆 We're not long into a new house with a different system, and yesterday I just put the system on manual all day (and night) at 20° and the house was evenly heated and used the same amount of gas as I have evert other day when I've had it on a timer (4 hrs morning, 5 hrs evening). I had to turn the heat down in the two rooms aye with the controller thermostat so that it took longer to heat up which allowed the other rooms to heat nicely and let the TRV on the radiator control the room. Have a look at Heat Geeks channel, some good info there too
This is so helpful - thank you. As it happens there are a couple of boilers out there which allow some people with a system boiler (not combi) to also set their boiler at 55. I have an intergas which allows me to set at 55 for Central Heating and 70 for Hot Water.
@@esecallum my radiators are luke warm all the time. I think I need to bump it up to 70C as we have -5c outside and the hallway thermostat never gets above 17c and even that takes all day to reach from 14c. I find it all so confusing.
@@esecallumno he is talking about a system boiler not a combi. I suspect He has a hot water tank that has to be heated above 55deg to kill off legionella. The temp of the heating is whatever will get your house to a comfortable temperature with the minimum of cycling (on off on off etc) with the right controls the boiler will turn down it’s power to try to match the temperature output with the heat loss. The lower the temperature the boiler runs at the more condensing it does and the more latent heat from the gas combustion gets used. You are correct with a combi since you are heating the water through the boiler on the way to the hot tap. No point in running up to 55 and having to mix it with cold at the tap. If you heat a hot water cylinder at 43 then you risk legionnaires disease.
is your boiler oil,gas,coal,electric and or wood. is it radiant heat cast iron radiators or copper heat fin.. does it have a indirect water heater? is your boiler a cold start or a maintained? there is not set point for a boiler temp. this is a good idea but the math does not work.
I have a Worcester i30 combi boiler, six years old. Its set at 55 degrees as set by the plumber who installed it. In the video about, Jamie states when the weather is very cold (I assume hovering just above and below -0) then the boiler needs to be put to 65 degrees? Surely a modern combi boiler like mine, it would automatically do this, or is it all manual input on these boilers?
@@jamiecureton2898 Thank you Jamie. Its a manual operation on my boiler. I will though take your advice when the weather, if it does, drop to very low single figures. Thanks!
Spent the last two hours watching videos on how to male gch more economical and efficient and still don't get this. I've just learnt about the flow and return temperatures now you are talking boiler temperature. What one is the boiler temperature?
Flow is the temperature you set at the boiler, the return temperature (some boilers show) is when the water has been round all the open (on) radiators and returned back to your boiler (obviously it's at a lower temperature as heat has been given off to the room(s). Condensing boilers actually condense at 54C but the lower return temperature the more efficient the boiler is. Bear in mind that in the really cold weather, at too low a flow temperature, it may not be hot enough to satisfy the target (room) temperature. As a (very) general guide, anything below -1 outside would benefit from a flow of around 60-70C, and generally Spring/Autumn temperatures the flow can be anything from around 50 -60C.
@@johnw2758 I don't think anybody boiler actually says flow and return. My boiler has a temp for a tap and a temp for the radiators. What should each one be?
@@anonanonanonanonanonagain Most boilers show the flow (radiator) temperature and you can sometimes press a button to see the return temperature. There are 2 icons for setting the flow, a radiator and a tap icon. The radiator icon is the flow temperature for the radiators, this time of year 60C is a good general temperature for that (if it's a condensing boiler), if it's not then I think the general rule is to set this to max (80C etc). The tap icon is for altering the temperature of the water that comes out of your taps. Obviously you don't want it scalding hot and by adding cold water to get a good (say bath) temperature is countertuitive, therefore a lower temperature is ideal. We have our radiator flow about 56C (this is all dependant on outside temp and how well insulated your house is), and our tap temperature at 48C. This allows us to fill a sink or have a shower without adding too much cold water.
Hi Jamie. Great video. I have a Baxi 105e combo boiler. It used to run at 80° but after repairs by a well known company, they have almost restricted the temperature dials and I can’t get the boiler above 55°. Thoughts?
@@jamie-theheatingguy4870 Thanks for your helpful posts here. can i ask some relevant questions please ?. i have a WB 30i condensing boiler, 2 years old, full TRV's and ESi "open therm" ? mobile CH thermostat, . No HW tank or boiler driven shower. At fitting, boiler CH flow was set at 75c and HW at 55c. All works fine but i'm guessing not economical. Following your advice to save cost, i have now reset the heating to 65c and may try even lower. Some you tube posts mention that boilers won't condense if flow temperatures are set too high, but don't explain or give temperatures. One engineer says his CH flow is set at 30c, so at 75c, i'm guessing i'm wasting money. I wrongly assumed a boiler would condense at all its designed operating temperatures. What are the min and max temperatures for both heating and HW ( i assume individually), for the boiler to work efficiently ?. Secondly, some engineers post that if flow temperatures are too low, there is a risk of legionnaires disease. Is this only a risk with stored water, ie, a hot water tank, or in all situations ?. It seems there is more to flow settings than simply cutting the gas bill. Please advise, thanks. 😁
@@julianhowarth1075 if you don’t have a hot water tank then no need to worry about legionella, the boiler overrides all this. I have my hot water set to 50 degrees, it might not condense but this is expected in hot water. Just be mor le mindful about not wasting the hot water that’s produced. The required flow temperature varies according to the outside temperature. The cold it is, the hotter your flow temp would need to be. If it’s too low then you’ll waste energy by not heating the room quick enough. Too high and it won’t condense, so there is some wastage there. It also depends on the design of the heating system and your radiator sizes in relation to your rooms- lots to consider. So with all that in mind, there is no perfect temperature, but if I installed a boiler I would typically set it to between 55 and 65 and see how it goes. In the depths of winter 55 might be too low but I would just see how my house feels and how it reacts to the heat. Sounds like you’re on the right track. Hope this helps
@@georgejetson4378 so childish. There's ample Proxi data showing that 7000 ppm CO2 was the norm during the most diverse period of flora and fauna explosion on earth.
@@georgejetson4378 I don't think he'll believe in things that have imperical evidence to the contrary. The CO2 debate is quite tenuous when you apply the scientific method, unfortunately though its the new religion and people get upset when their new god is questioned...hence your banal remarks. I'd suggest rather than jumping to the defence of the extraction of wealth from the poor racket, you actually go off and apply the scientific method to some proper research.(ovoid the BBC).
Jamie, you are the hero! I fixed our Boiler by following your instructions and got HOT WATER!!!! Now we can take a bath!! Thank you so much for this very INFORMATIVE VIDEO!!!
Very Funny :)
My home has a hot water storage tank and I have been running the boiler stat at 65c. A year on and the gas usage like for like is a third of what it was when we first moved in with the boiler set at max 85c. Saving £500+ a year now!!
We have also had the noisy old pump replaced with a new smart variable speed pump.
With current energy prices having your heating controls set optimally for efficiency and comfort can save you £100 or £1000s
Thanks... very informative, wish I had got this straight answer when my boiler was installed. I got told to set my brand new condensing boiler to 75!
Mines perfect at 69
@Minix Tvbox I'll count in the Am 👍
mine was set at 75 after installation and I kept the setting for a few days.... I reduced it to 65 and there was a definite saving in gas
Condensing mode starts at a return water temp of 55c. Then it is a gradient… the cooler the return the more efficient and more condensing it is doing. Heat Geek also did a video on this, you want that water in your rads as cool as possible to keep the house warm.
That is correct.
The reason for the recommendation of 55 degrees is so that the heat being emitted the radiators during warmer months is a much nicer temperature. Otherwise the heat curve of the property will all over the place.
I have a Vaillant condensing boiler, radiators, external temperature sensor.
The house is well insulated too..
But whatever heat curve I sett the radiator water goes always over 50-55
Is there a way to limit the temperature? I don't expect negative 20c° outside..
The curve is now at 0.90.. Can I sett something beside the heating curve?
I've watched this one, but it's for vitodens
ua-cam.com/video/tK38GyHTsbY/v-deo.html
@@luckystrike656 yea on the Vaillant you can set a max flow temperature.
You’ll need to go into the settings by following the procedure in the manual and from there you can set the max flow temp.
I’ll be honest, I’m not on the tools any more so I can’t remember exactly how to do it for all boilers, but for different Vaillant’s there is a different procedure so make sure you read the book.
Thanks
@@luckystrike656 you should be able to limit the maximum flow temperature in the settings. Sounds like your heat curve set too high or your weather comp ain't set up right.
It seems like cooler temp will make the boiler run constantly (or at least very frequently). Is that ok? And is that most efficient?
The 55C rule for condensing is not the boiler temperature it is the return temperature from the radiators. As radiators should have a 13c to 20c temperature drop across them a boiler set to say 65c will still condense as the water entering the boiler should be around 45c to 50c.
Ha ha ha good luck getting that differential across a radiator. No chance.
Just checked mine and flow going out is 58oc and coming back in at 54oc and that is going into the boiler settings showing flow and return
@@gaeryfleming172 so you have a 4 degree differential.
Yes 4oc is that OK
3 downstairs radiators are fully open and bedroom ones upstair are on half way
This is all well and good if you have combi system, however like myself with a conventional system you may as well just leave the boiler near the max temperature because it will never condense in hot water mode which is used 100% of the time, even with the balancing valve on the coil throttled right down the return temperature will still very quickly exceed 55 degrees, so i don't see much point chasing slightly extra efficiency I'd much rather have faster hot water and heating times!
Hi NRG, there are controls available that allow the system to have 2 different temperature for heating and hot water.
Heating will be set for condensing and hot water will be max for rapid re heat. It then only allows either heating or hot water to be used at separate times. But other than that your point is valid 😊
If you have a newer condensing boiler that has outside temp sensors try to utilize outdoor air setback. It will lower setpoint based on outdoor temperature. Have a professional make sure your boiler is setup right.
I do have an outside temperature sensor but the setpoint is pretty much always the same, whatever heating curve a sett. Right now is at 0.90...
Thanks for this-what is the best temperature setting for the boiler for the water and the bar ?To not spend more money.Thanks again
The bar isn’t as important for efficiency but a recommended range of between 1 and 1.5 when cold is good but not the end of the world if it goes slightly higher.
For hot water it depends if you have a hot water tank or not. If you don’t then 50 degrees is a good temperature to aim for.
Hope this helps 😊
I watched a million videos. NOBODY explains what temperature an older non condensing boiler should be set at for max efficiency 😢
I think it's max
Nice one mate cheers
thanks for the information.do you have any videos explaining the valves on the side of the radiators.i have a radiator in my bedroom that has two valves but no caps on them so i dont know what they do.if i turn one it makes the radiator boiling hot and turned off its off.i dont seem to be able to vary the temperature.
Surely if you have radiators a little oversized then the water flowing through does not need to be as hot. Problem today I see when new rads are fitted they go as small as possible the engineer not calculating rad sizes properly
Correct as there is more surface area.
Its the return temperature that matters, right? Above 55 does not condense but the lower the return temp the more efficiency. I tried setting the outlet to 45 but unfortunately the system struggles. With bigger rads this would work fine but its an expensive solution. I wish I had a system that modulates the boiler temperature according to outside temperatures
I think it's flow temperature that people are referring to here. And there shouldn't be a need to make such smaller adjustments normally - the boiler would just run longer when the outside temperature is lower, in order to reach the desired warmth (set by your thermostat). For instance set the boiler's flow temperature to 50 degrees C and forget it - if there is insufficient insulation in the property or the radiators are small etc then you can set flow to 55 and that should be it.
Get a thermostat with opentherm capacity (Honeywell Lyric does this) and make sure your boiler can do opentherm. It’s plug and play. I prefer opentherm to outside weather compensation.
That's great... but my boiler doesn't have temperature scales on the knobs, nor any digital screen or temperature indication.
What about do you have Johnny? Do you the make and model?
My Potterton Promax He Store is at 45C, I tried 35C, but it complains and starts to sound like a T-Rex. I was trying to simulate an ASHP. So far 45C is fantastic with the outside temp between 2 to 6C and the thermostat set to 17C. My house glows with warmth, and it doesn't cycle a great deal. I have mine switch on at 2200 to 2400 and 0700 - 0900 (when am in) When I get home (2230)I turn on a fan heater and IR panel for my TV room, once it gets upto 18C (3 minutes) I turn them off and let the radiators take over. Seems comfy doing this.
Hot water is set to 80ish C. Every now and again I will do a high temperature cycle. I don't want bugs in the water. They love it at these temps.
Will the app allow me to adjust the temperature of the boiler or can it only be controlled by a Gas Safe Engineer from the boiler itself?
Also, I've heard that condensing mode is important to even system boilers as the heat exchanger will stay cleaner and the boiler will burn more efficiently. Why do you not suggest running the lower temp (with oversized rads) on system boilers as well?
What about the anti cycle time setting, surely this affects it? E.g. default on my WB is 5 minutes ( I think it's around 20 minutes on a Valliant) but it can go from 3 to 45 minutes. By using a lower flow and a higher anti cycle time (say 30 minutes) the usage on mine in -3 C conditions, flow 55C, anti cycle 30 minutes, got it up to 18C target temp. My question is, what is the usual ratio, low flow high anti cycle or higher flow (60 ish) and a lower anti cycle time?
Help Jamie ! We have Buderus and we cant find a way to decriese heatinh without heating stoping working. Can you help please ?
Hi all. I have a Vaillant Ecotec Pure combi boiler 26.1 kW and I'm heating a 120 square meter home (9 radiators, the biggest one is 100x60 cm, 22). Is it OK if I set the flow temp at 65 Celsius? Outside is -1, 0 C and I cannot get 23 C in my home. So, if I ramp up the flow temp at 65 C will I lose the condensing efficiency? Thanks
No. Your system will lose at least 10c by the time water returns. Just make sure your rads are properly balanced. But set temp as low as possible for max efficiency
Has the vaillant ecotec vuw 286/7 -2 got the comfort zone cannot see how to turn if off as no C showing
Does the 55 degree setting apply to both the heating and hot water? I have just had a combi installed and have the heating temp set at 65 degrees and the hot water at 45 degrees which I find ideal without having to mix cold water
Hi, Jamie here from the video.
You can set your hot water on a combi boiler to whatever you want in my opinion. I always went 50 degrees. What it actually achieve will vary depending on the time of year too.
Hope this helps
@@We-Are-FlowState Many thanks for the reply. I have the heating flow down to 60 degrees now and maintain the DHW at 45 which is fine
100th comment 🎉
🎉🎉🎉🎉 congratulations - you win absolutely nothing but the pride of being the 100th comment 😊
Thank you, Jamie. That was very interesting. I live in a two bedroom flat, with 5 radiators. I have a Glow Worm Betacom2 24 combi-condensing boiler. I also have the Tado Mulit-room Control, with Tado SRVs on each radiator. I have also balanced the radiators.
My Question is: given that I need to keep the return temperature below 55C, what temperature should I set the boiler flow temperature to, in order to get the Tado system to operate efficiently, while also keeping the boiler operating in Condensing mode?
The video on the British Gas website, advises to set the boiler temperature to the Maximum - even with a combi-boiler - which seems to contradict, that which you and other have said.
British Gas are in the business of selling gas, it would make sense that they tell you to waste it.
Well obviously you will be fine to set it at 55 for starters. If all your rads are balanced properly I would say that the heat loss from the rads would be 10c minimum, so setting the output at 65 should be fine. But if you are warm, the lower the better
It should be set at the minimum temperature needed to sufficiently heat up your property. The lower the better, if you'd like efficient heating in condensing combi boilers. The better your property is insulated, the lower your boiler's temperature can be. For example, if your flow temperature is set to 40 degrees C and you feel warm enough (i.e. your room or property doesn't lose heat faster than the radiators warm it up), then that's ideal.
In spring/autumn our rads are set to about 30-35c as it gets colder we can get away with 45c flow temp but now we have an opentherm thermostat which does it for us.
In the winter ❄️ season I’ll set my heat at 67 during sleep and 70 degrees during the day
1) Does a modulating boiler only modulate down the burner, or does it also modulate the rad pump flow rate?
2) is the modulation power (kw) set by the opentherm stat or is the flow temp set by an opentherm stat and then the boiler chooses the appropriate kW?
3) if I use a weather compensating control like a google nest, does that automatically set the boiler output or does it set the flow temperature?
1. On some boilers depending on the version of opentherm they are working to, the opentherm can tell the boiler to modulate the pump at burner on/burner off. Our ideal Vogue runs the pump at high when the burner goes off and then modulates the pump lower when the burner is on.
2. The opentherm controller will tell the boiler what flow temperature it wants, the boiler then modulates via it’s internal safety circuits the burners to achieve that flow temp.
3. Weather compensation is different in that it utilises the outside air temperature and you set a linear heat curve e.g at 0c outside your flow temp would be 60c but at 15c outside your flow temp would be 25c. The thermostat will just tell the boiler what it wants and the boiler will adjust it’s output… I’ve tried both and I prefer opentherm as it’s based on the actual internal conditions the greater the diff between set point and actual temp the harder the boiler works.
Thanks for this - I have a condensing combi-boiler, but the heating dial only has numbers rather than temperatures - how do the numbers equate to temperature?
The numbers could from 30 to 80, try the middle value
Hi
I have a condensing boiler and radiators, and external sensor and calormatic control.
Even if I read the outside temperature at 9C°, with a heating curve set to 0.90, the boiler is pushing the water over 50C° and my house goes over the sett 22C°
Is there anything I can do to limit the radiator water temperature to max 55C°? A know it will not be negative 20C° outside.. I'm not in the NorthPole :)
Hi Jamie! I’ve never had radiators to heat any home I’ve lived in. I just had the logic combi c30 put in because I’ve never had to use radiators I’ve no idea is it safe to lower my radiators put the boiler at around 60 degrees? My main question is can I keep the boiler/ radiators running all day until it get to warm? I would really appreciate your help in regards to that. I’ve lived in hot country that never needed heating. Totally lost. Thanks🤯
Hey! I have same boiler, so yes you can! There is a school of thought that you lower the flow temperature of the heating system but leave it running longer... This is better for the system apparently because its not cycling on and off and also can save gas because its not having to do regular blasts of heat. Or something 😆
We're not long into a new house with a different system, and yesterday I just put the system on manual all day (and night) at 20° and the house was evenly heated and used the same amount of gas as I have evert other day when I've had it on a timer (4 hrs morning, 5 hrs evening). I had to turn the heat down in the two rooms aye with the controller thermostat so that it took longer to heat up which allowed the other rooms to heat nicely and let the TRV on the radiator control the room. Have a look at Heat Geeks channel, some good info there too
55 degrees is return flow temp
This is so helpful - thank you. As it happens there are a couple of boilers out there which allow some people with a system boiler (not combi) to also set their boiler at 55. I have an intergas which allows me to set at 55 for Central Heating and 70 for Hot Water.
55 FOR CH. 43 FOR HW.
@@esecallum my radiators are luke warm all the time. I think I need to bump it up to 70C as we have -5c outside and the hallway thermostat never gets above 17c and even that takes all day to reach from 14c. I find it all so confusing.
@@esecallumno he is talking about a system boiler not a combi. I suspect He has a hot water tank that has to be heated above 55deg to kill off legionella. The temp of the heating is whatever will get your house to a comfortable temperature with the minimum of cycling (on off on off etc) with the right controls the boiler will turn down it’s power to try to match the temperature output with the heat loss. The lower the temperature the boiler runs at the more condensing it does and the more latent heat from the gas combustion gets used.
You are correct with a combi since you are heating the water through the boiler on the way to the hot tap. No point in running up to 55 and having to mix it with cold at the tap. If you heat a hot water cylinder at 43 then you risk legionnaires disease.
@@davideyres955 really? how come none of had legionaires after 20 years of above tempd...its a scare thing.
The Urban Plumbers recommend intergas. I''ve a new navien. It's many levels above the previous Bosch I had
is your boiler oil,gas,coal,electric and or wood. is it radiant heat cast iron radiators or copper heat fin.. does it have a indirect water heater? is your boiler a cold start or a maintained? there is not set point for a boiler temp. this is a good idea but the math does not work.
ive put a boiler energy manager on mine resulting in lower fuel bills.
I have a Worcester i30 combi boiler, six years old. Its set at 55 degrees as set by the plumber who installed it. In the video about, Jamie states when the weather is very cold (I assume hovering just above and below -0) then the boiler needs to be put to 65 degrees? Surely a modern combi boiler like mine, it would automatically do this, or is it all manual input on these boilers?
Hi Anonanon, depends on what controller you have installed but chances are you will need to do this manually 😊
@@jamiecureton2898 Thank you Jamie. Its a manual operation on my boiler. I will though take your advice when the weather, if it does, drop to very low single figures. Thanks!
Spent the last two hours watching videos on how to male gch more economical and efficient and still don't get this. I've just learnt about the flow and return temperatures now you are talking boiler temperature. What one is the boiler temperature?
Flow is the temperature you set at the boiler, the return temperature (some boilers show) is when the water has been round all the open (on) radiators and returned back to your boiler (obviously it's at a lower temperature as heat has been given off to the room(s). Condensing boilers actually condense at 54C but the lower return temperature the more efficient the boiler is. Bear in mind that in the really cold weather, at too low a flow temperature, it may not be hot enough to satisfy the target (room) temperature. As a (very) general guide, anything below -1 outside would benefit from a flow of around 60-70C, and generally Spring/Autumn temperatures the flow can be anything from around 50 -60C.
@@johnw2758 I don't think anybody boiler actually says flow and return. My boiler has a temp for a tap and a temp for the radiators. What should each one be?
@@anonanonanonanonanonagain Most boilers show the flow (radiator) temperature and you can sometimes press a button to see the return temperature. There are 2 icons for setting the flow, a radiator and a tap icon. The radiator icon is the flow temperature for the radiators, this time of year 60C is a good general temperature for that (if it's a condensing boiler), if it's not then I think the general rule is to set this to max (80C etc). The tap icon is for altering the temperature of the water that comes out of your taps. Obviously you don't want it scalding hot and by adding cold water to get a good (say bath) temperature is countertuitive, therefore a lower temperature is ideal. We have our radiator flow about 56C (this is all dependant on outside temp and how well insulated your house is), and our tap temperature at 48C. This allows us to fill a sink or have a shower without adding too much cold water.
Also 'stored hot water' should never be less than 60 degrees centigrade so that bacteria's cannot flourish ! dx
Wat should an ideal logic esp1 30 vombi boiler be set at for water
Hi Jamie. Great video. I have a Baxi 105e combo boiler. It used to run at 80° but after repairs by a well known company, they have almost restricted the temperature dials and I can’t get the boiler above 55°. Thoughts?
They have prob changed the circuit board and not put the dials in the correct place.
@@magicgsuk6312 absolutely correct. I’ve just checked it and you’re absolutely correct. Thank you.
I’ve sent me sort code and account number over😂
So now December 65
I just want some warmth...
You don't mention which temperature ie, heating or hot water ?.
Hi Julian,
It depends what sort of system you have, do you have a Combi boiler or hot water tank?
@@jamie-theheatingguy4870 Thanks for your helpful posts here. can i ask some relevant questions please ?.
i have a WB 30i condensing boiler, 2 years old, full TRV's and ESi "open therm" ? mobile CH thermostat, . No HW tank or boiler driven shower.
At fitting, boiler CH flow was set at 75c and HW at 55c. All works fine but i'm guessing not economical.
Following your advice to save cost, i have now reset the heating to 65c and may try even lower.
Some you tube posts mention that boilers won't condense if flow temperatures are set too high, but don't explain or give temperatures.
One engineer says his CH flow is set at 30c, so at 75c, i'm guessing i'm wasting money.
I wrongly assumed a boiler would condense at all its designed operating temperatures.
What are the min and max temperatures for both heating and HW ( i assume individually), for the boiler to work efficiently ?. Secondly, some engineers post that if flow temperatures are too low, there is a risk of legionnaires disease. Is this only a risk with stored water, ie, a hot water tank, or in all situations ?.
It seems there is more to flow settings than simply cutting the gas bill.
Please advise, thanks. 😁
@@julianhowarth1075 if you don’t have a hot water tank then no need to worry about legionella, the boiler overrides all this. I have my hot water set to 50 degrees, it might not condense but this is expected in hot water. Just be mor le mindful about not wasting the hot water that’s produced.
The required flow temperature varies according to the outside temperature. The cold it is, the hotter your flow temp would need to be. If it’s too low then you’ll waste energy by not heating the room quick enough. Too high and it won’t condense, so there is some wastage there. It also depends on the design of the heating system and your radiator sizes in relation to your rooms- lots to consider.
So with all that in mind, there is no perfect temperature, but if I installed a boiler I would typically set it to between 55 and 65 and see how it goes.
In the depths of winter 55 might be too low but I would just see how my house feels and how it reacts to the heat.
Sounds like you’re on the right track. Hope this helps
I don't give a toss about CO² footprints. It's BS
I guess you don't care about your energy bill either...
@@DavidTheScientist he will because it is tangible.
You probably also think the earth is flat, the moon is made of cheese, and mankind is only 6000 yrs old.
@@georgejetson4378 so childish. There's ample Proxi data showing that 7000 ppm CO2 was the norm during the most diverse period of flora and fauna explosion on earth.
@@georgejetson4378 I don't think he'll believe in things that have imperical evidence to the contrary. The CO2 debate is quite tenuous when you apply the scientific method, unfortunately though its the new religion and people get upset when their new god is questioned...hence your banal remarks. I'd suggest rather than jumping to the defence of the extraction of wealth from the poor racket, you actually go off and apply the scientific method to some proper research.(ovoid the BBC).
Starts 45 seconds in
carbon footprint give me a fucking break.
Well said...
Good vid apart from the carbon footprint crap
The carbon futprint is shit....does prince charles abide by it...no.