Constant Room Temperature

[Dunbar]

I'm looking for a more constant room temperature if that is possible. My boiler is a Vaillant Eco Tech plus 418 and I have a basic Honeywell room stat. I have the stat set so the boiler fires up at 20.6. It goes off at around 21.4 and then carries on heating up to approx 21.9. I therefore have a gap of 1.3 degs between the the time the room reaches max temp and the boiler coming on again. I don't want to turn the stat up because the room will get too hot for my preference, so I was wondering if there is anything I can do to bring the two temps closer together (boiler comes on around 21, but still switches off after warming room for .5 deg). Not really up to date on Smart stats/programming but would switching to that option assist my issue?

Thanks in advance for any advice.,

 

[SimonG]

For 1.3 degrees I wouldn't bother, or turn it down 0.5 a degree.

 

[king of pipes]

As above you won't control it by 1.5 degrees turn to 20 degrees and monitor it again bit of trail and error. Kop

 

[Chuck]

I'm looking for a more constant room temperature if that is possible. My boiler is a Vaillant Eco Tech plus 418 and I have a basic Honeywell room stat.

A more sophisticated thermostat will help considerably. One that uses 'time proportional integral' control will improve the control and keep the measured temperature within a 0.5°C band. For example, Honeywell DT90E (simple) CM707 (programmable). These can both be installed by a DIYer with reasonable electrical skills.

I believe that your boiler is compatible with quite sophisticated Valliant smart controls but you'll need a heating engineer to install them for you, which will be a bit more costly.

 

[siricosm]

I'm looking for a more constant room temperature if that is possible. My boiler is a Vaillant Eco Tech plus 418 and I have a basic Honeywell room stat. I have the stat set so the boiler fires up at 20.6. It goes off at around 21.4 and then carries on heating up to approx 21.9. I therefore have a gap of 1.3 degs between the the time the room reaches max temp and the boiler coming on again. I don't want to turn the stat up because the room will get too hot for my preference, so I was wondering if there is anything I can do to bring the two temps closer together (boiler comes on around 21, but still switches off after warming room for .5 deg). Not really up to date on Smart stats/programming but would switching to that option assist my issue?

Thanks in advance for any advice.,

This answer provides no easy fix, but I reply anyway.

If you could narrow the differential on your room stat to .5 degrees, then your boiler would likely short cycle, unless the water volume in your system is very large (i.e. old cast iron rads). One way to avoid this is to put a buffer tank between your boiler and the radiators. The boiler would be controlled by a cylinder stat on the buffer tank, which can have a 5C or more differential, and there would be no house (room) stat. All the radiators would be controlled by TRVs, if you like programmable. The rads will then maintain an even temperature, and there will be no temperature cycling at all in the rooms. This also allows different temperatures in each room as desired.

 

[Dunbar]

Thanks for your replies, will check out your suggestions.

 

[Brambles]

Evohome will allow you to zone each room and certainly improve or even fix your current issue. Sadly it comes at a hefty price.