Central Heating Question, anyone?
Discussion
I've been given the following two conflicting statements from so called knowledgable people, which is the correct advice?
1) Have our boiler heating set to high, almost max, and use individual radiator valves to control how much heat is given to each room,
or
2) Have our boiler set to low, almost minimum, and keep individual raidator valves fully open / set to max.
Which is the most efficient/correct setup to avoid devastating heating/gas bills?
Thanks in advance
1) Have our boiler heating set to high, almost max, and use individual radiator valves to control how much heat is given to each room,
or
2) Have our boiler set to low, almost minimum, and keep individual raidator valves fully open / set to max.
Which is the most efficient/correct setup to avoid devastating heating/gas bills?
Thanks in advance
It also depends on your boiler. Some have simple on/off control of the burner, some modulate. ISTR that a long, controlled burn is more efficient and less hard on the boiler than constantly turning on and off.
You should probably set your rads and boiler how you feel, and then keep an eye on how often and how long it's turning on. That'll be very specific to your set up.
You should probably set your rads and boiler how you feel, and then keep an eye on how often and how long it's turning on. That'll be very specific to your set up.
The thermostatic valves should be set to the same whether your going with option 1 or 2. If you're running your boiler on low the chances are the valves will not close anyway as the house probably wont be warm enough but by chance some of them do close then you will have saved some money.
Option 1. Rads should be around 80 degrees. Hot rads heat a room quicker. Luke warm rads will take an age. The room stat will turn the boiler off when it gets up to temperature.
Do set it just off max. It'll also warm a cylinder up quicker if you're that setup.
Condensing boilers work best flat out also, so make it work.
Do set it just off max. It'll also warm a cylinder up quicker if you're that setup.
Condensing boilers work best flat out also, so make it work.
As above. It's important to bear in mind a couple of things...
Firstly, radiators are sized for a given volume based on a set flow temperature. If they don't get it you may well not keep up with the heat losses.
Second, if you are running a fully pumped system the cylinder will want 65 degrees, say, if the boiler flow is set lower it means that the cylinder will never attain temperature, the valve will remain open creating a short circuit back to the boiler and causing it to go out on the thermostat more often, again causing problems with heat losses. When Honeywell designed their 'S'-plan the idea was that the boiler stat would be flat out. I tend to set it a little lower, to be honest, to avoid nuisance hi-limit stat issues.
Firstly, radiators are sized for a given volume based on a set flow temperature. If they don't get it you may well not keep up with the heat losses.
Second, if you are running a fully pumped system the cylinder will want 65 degrees, say, if the boiler flow is set lower it means that the cylinder will never attain temperature, the valve will remain open creating a short circuit back to the boiler and causing it to go out on the thermostat more often, again causing problems with heat losses. When Honeywell designed their 'S'-plan the idea was that the boiler stat would be flat out. I tend to set it a little lower, to be honest, to avoid nuisance hi-limit stat issues.
It's a good point about the temperature drop on the rads though. You could end up with rooms not getting any heat at all, and certainly taking an age to heat up.
Rads are sized to work at a particular temperature. People who've been sold dodgy heat pump systems find that they can't keep their house warm when the hot water isn't so hot.
Rads are sized to work at a particular temperature. People who've been sold dodgy heat pump systems find that they can't keep their house warm when the hot water isn't so hot.
Tuna said:
Rads are sized to work at a particular temperature. People who've been sold dodgy heat pump systems find that they can't keep their house warm when the hot water isn't so hot.
A heat pump isn't the same as a boiler.Boilers are usually oversized, to cater for extremes and because they don't cost much more.
As heat pump capacity goes up, they cost more - and over 15kW output needs three phase.
In addition as it's gets colder outside the performance drops of.
However if a heat pump is producing say 10kW, all this will end up in the house via radiators. The problem emerges when the house is losing 10kW when it's only 15c inside. House temp won't go up.
caziques said:
A heat pump isn't the same as a boiler.
Boilers are usually oversized, to cater for extremes and because they don't cost much more.
As heat pump capacity goes up, they cost more - and over 15kW output needs three phase.
In addition as it's gets colder outside the performance drops of.
However if a heat pump is producing say 10kW, all this will end up in the house via radiators. The problem emerges when the house is losing 10kW when it's only 15c inside. House temp won't go up.
Sorry, that wasn't the point. Quite a few heat pump systems run at a much lower temperature, and there have been reports of installers putting them in as 'green boiler replacements', for the owners to find out that their rads can't heat the house any more. If you run your rads at, say 55, they can turn out to be undersized for the rooms.Boilers are usually oversized, to cater for extremes and because they don't cost much more.
As heat pump capacity goes up, they cost more - and over 15kW output needs three phase.
In addition as it's gets colder outside the performance drops of.
However if a heat pump is producing say 10kW, all this will end up in the house via radiators. The problem emerges when the house is losing 10kW when it's only 15c inside. House temp won't go up.
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