Turning heating/boiler completely off during the night?

andre_xs

Dear All,
we recently got a new boiler (Viessmann Vitodens 100 combi boiler) installed. Unfortunately, it frequently turns on during the night for a short time (although there's no tank in it, to keep the water ready and warm? It does so even if the thermostat is set to like 13 degrees or so, so it's not the heating) and my wife wakes up from that.

Do you know whether this can be changed by settings? If not, we thought about properly turning off the boiler each night, but I was wondering whether this is maybe bad for the boiler in the long term? (some stuff doesn't like to be shut down and powered up constantly).

Temperature-wise it should be fine, we are mid-terrace and even in winter the house doesn't really cool down too much.

Best wishes,Andre

moneysaver1978

Check if there's an Eco setting.

Our boiler (Worcester Greenstar combi) did the same and when we last had it serviced, the engineer recommended us to enable the Eco if we don't need or want hot water instantly. This also helps to prolong the life of the boiler.

What this does is that the boiler heats up water only when you turn the hot water tap on, so it takes slightly longer for the hot water to come through the taps.

Rodders53

Have you asked your installer?

Have you read the manuals?  (Both User and Installer/Service manuals are available online.)
https://viessmanndirect.co.uk/Catalogue/Residential-Boilers/Viessmann-Combi-Boilers/Vitodens-100-W-Combi-Boilers

1) Most probable (as suggested already) is the small HW tank for 'near instant' HW being reheated.  Wasteful things. Turn off the feature.

2) Alternative is a frost protection stat (if supplied/fitted) being set too warm and coming on overnight. 

There may be other less obvious reasons.

FreeBear

Rodders53 said: 1) Most probable (as suggested already) is the small HW tank for 'near instant' HW being reheated.  Wasteful things. Turn off the feature.

Pretty sure it is just the Vitodens 111 that has an internal storage tank. The 100 is very similar to the 050 that I have. The boiler will fire up at regular intervals to keep the internals hot just in case you want instant hot water. I agree with others, a wasteful "feature", but easily disabled from the front panel. from the instruction manual -

MysteryMe

I think 13 degrees may be a little high for overnight? I got the Vitodens 111 installed about 7 months ago and currently have the temp set for 10 overnight but may lower it if the temp drops and the heating starts kicking in. Can't say if it heats up the water overnight as it does not disturb me.

FreeBear

MysteryMe said:

I think 13 degrees may be a little high for overnight? I got the Vitodens 111 installed about 7 months ago and currently have the temp set for 10 overnight but may lower it if the temp drops and the heating starts kicking in.

10°C is way too cold for me & the cat. Even 13°C is too low. Currently have the night time temperature set for 16°C, but I might bump that up to 17°C over Christmas - It all helps to reduce condensation forming on the walls along with the attendant black mould. Fortunately, I don't lose huge amounts of heat overnight (only dropped ~2°C last night with 1-2°C outside).

MysteryMe

16 degrees overnight would be far too hot for me. I have the window open as well. Don't get any condensation in the house.  I thought I was a southern softie, obviously not lol!

FreeBear

Should have mentioned - Have turned the pump speed right down, and don't notice any noise when the heating is on.

Needed to dial it back so that I could get the correct temperature drop across the radiators. The lack of noise is a big bonus.

andre_xs

Apologies for the late reply, I just wanted to thank you all. Turning on Eco mode indeed did the trick. It now does take a bit longer for warm water to come, but it's really not much longer, so no problem at all.

koalakoala

As a matter of interest what temperature do folk set during the night?

Flugelhorn

koalakoala said:

As a matter of interest what temperature do folk set during the night?

our heating is off at night