Feeling Colder yet Thermostat at Same Setting.

david1946

BUFF said:

I hate to say it but it can also be part of the aging process https://www.mobilityhelp.co.uk/why-do-old-people-feel-cold/

That could be the answer, I have recently been diagnosed with diabetes.

wittynamegoeshere

DerwentMailman said:

However I have come to realise that a comfortable indoor temperature of say 20C with say an ambient outdoor of 10C always feels way warmer than the same 20C (which it is now) and an outdoor of 0C.   

If feels warmer because it IS warmer.  The thermostat is somewhere within the house, as are the radiators.  As the outside temperature gets lower, the windows and external walls get colder.  Any point between the thermostat and any outside wall is likely to be colder when the outside temperature is lower.

The thermostat fixes the temperature of an arbitrary part of the interior.  If it's colder outside then you'll need to turn it up to achieve the same temperature in an area that is closer to an outside wall (usually pretty much everywhere).

Noting the diabetes issue, it's entirely possible that it feels colder because it is.  Thermostats are just a comfort level really.  If you're cold, turn it up.  It would be worthwhile to buy a portable thermometer you can place around the room, nothing elaborate needed, just a cheap one will be fine.  You'll probably see huge variations, especially closer to the outside walls.

Norman_Castle

david1946 said:

I have noticed that the radiators, when they get hot as the heating cycles on and off, don't seem to feel as hot in the evening.

In the morning you can barely keep your hand on the radiators but in the evening you can. 

In the morning the heating system is trying to raise the temperature, in the evening it is maintaining a temperature.  

[Deleted User]

wittynamegoeshere said:

DerwentMailman said:

However I have come to realise that a comfortable indoor temperature of say 20C with say an ambient outdoor of 10C always feels way warmer than the same 20C (which it is now) and an outdoor of 0C.   

If feels warmer because it IS warmer.  The thermostat is somewhere within the house, as are the radiators.  As the outside temperature gets lower, the windows and external walls get colder.  Any point between the thermostat and any outside wall is likely to be colder when the outside temperature is lower.

The thermostat fixes the temperature of an arbitrary part of the interior.  If it's colder outside then you'll need to turn it up to achieve the same temperature in an area that is closer to an outside wall (usually pretty much everywhere).

Noting the diabetes issue, it's entirely possible that it feels colder because it is.  Thermostats are just a comfort level really.  If you're cold, turn it up.  It would be worthwhile to buy a portable thermometer you can place around the room, nothing elaborate needed, just a cheap one will be fine.  You'll probably see huge variations, especially closer to the outside walls.

On dear I stand corrected.

FYI, my boiler thermostat is wireless and portable - it usually sits within arms reach of whatever room I am in.  I also have a another portable monitor that measures temperature and humidity.  Perhaps my post should have made this quite clear.  But thanks for your thoughts anyway.

I know there are different temperature zones within our dwelling and draughts caused by opening and closing doors (usually for a wandering cat) adds to this feeling of being colder than one ought to feel.  Getting older does not help either  

Astria

BikingBud said:

@Astria do you have a calibrated temperature monitoring and logging system? Where are you measuring your 0.5 deg C. Have you established any correction curves between your measured 0.5 deg C overshoot and the indicated boiler temp

Interestingly you are not able to confirm within your measuring tolerance if the compensating function works or not

Calibrated? No. Although I did use the thermostat on the wall which displays the current temperature and controls the boiler. I don't care what the thermostat actually says as long as I'm at a comfortable temperature - I'll turn it up if I'm cold and down if I'm too warm.

But like I said, when the thermostat was in "smart" mode, all it seemed to do with cycle the boiler more often, it was like it was giving the heating small bursts to try a maintain a temperature instead of waiting for the temperature to drop and then turning it back on until that temperature is reached. I'm not saying this is wrong and for some people they might like the idea, but for me I don't like it because it causes the boiler to switch on/off more often, and the main advertised point of it "saving fuel/gas, thus saving you money" I couldn't confirm as the amount of gas different I couldn't reliably measure with just my current meter over the period I measured it for (several days, but since I can't control the outside temperature I can't call it a controlled test). It might be that it does indeed save you money if you run it for a year with a specific boiler, but the opposite could be true with some boilers because they could use more energy for each cycle, or that the higher frequency cycling could cause parts to wear out faster.

Yes, it's all "could" and "maybes" and "your mileage may vary" - it's just my opinion. Yours may differ.

wittynamegoeshere

Pretty much all thermostats in the past were deliberately designed to have hysteresis.  This is a fancy word that means that the "off" temperature is higher than the "on" one.  E.g. if you set it to 20 then it might heat until it gets to 21, then switch off until the temperature drops to 19.  This is absolutely intentional, by design, and intended to avoid the excessive cycling you describe.

Sadly, sometimes the whizz-kids who design the current tech products may know all about smartphone integration, flashing lights and pretty displays but perhaps don't have the experience to understand the sort of knowledge that was built up over the decades of development of the old-fashioned ones.  Newer sometimes isn't better.

It MAY be possible to set up this sort of behaviour on your smart thermostat, perhaps in some advanced menu or something.  You're absolutely right, it's a waste of energy and causes unncessary stress on all components for it to be continually switching on and off.

It's perfectly possible that your super dooper smart home thing may just be junk.

red_flump

It's not a waste of energy, it sounds like standard Honeywell wired/wireless or remote behaviour.
Keeps to the set temperature very closely, the cycling also helps keep it near the condensing temperature.

It can be turned off in the settings, but I've been using it for years and I'm impressed.

Astria

red_flump said:

It's not a waste of energy, it sounds like standard Honeywell wired/wireless or remote behaviour.
Keeps to the set temperature very closely, the cycling also helps keep it near the condensing temperature.

It can be turned off in the settings, but I've been using it for years and I'm impressed.

How does constant cycling help it keep it near the condensing temperature? The water returning to the boiler will likely be cooler if you don't cycle so often and that's what you want ?

But yes, it'll keep very closely to the temperature you've set, but at what cost if the boiler is constantly switching off and on?

tux900

Astria said:

But yes, it'll keep very closely to the temperature you've set, but at what cost if the boiler is constantly switching off and on?

I've been using Honeywell's TPI control algorithm for around 15 years now in two houses and not had a single boiler/heating failure so, on that limited sample size at least, don't believe it to be an issue. It must of course have an impact, but I've yet to see any real consequence and you can always limit the cycle times if you were concerned about letting it have free reign. The stability of control, including completely eliminating over/undershoot, makes it a big win in my book and definitely adds to the perceived 'comfort' levels. For boilers that don't support a variable demand signal I'd highly recommend it.

BUFF

Astria said:

red_flump said:

It's not a waste of energy, it sounds like standard Honeywell wired/wireless or remote behaviour.
Keeps to the set temperature very closely, the cycling also helps keep it near the condensing temperature.

It can be turned off in the settings, but I've been using it for years and I'm impressed.

How does constant cycling help it keep it near the condensing temperature? The water returning to the boiler will likely be cooler if you don't cycle so often and that's what you want ?

But yes, it'll keep very closely to the temperature you've set, but at what cost if the boiler is constantly switching off and on?

A Greenstar plus Comfort II RF should allow for modulation & load compensation thereby allowing the system to run lower temperatures hence better condensing. It should also reduce cycling .

Astria, what boiler/thermostat combo do you have?