Worcester Bosch CDC classic with 'Wave' controller

17 Sep 2005
Reaction score
United Kingdom
Looking for some advice and or comments regarding my new combo boiler.

I had a new Worcester Bosch 38cdi Classic combi boiler and smart 'Wave' controller / thermostat installed last January (i.e. 10 months old) by a local gas safe registered heating engineer. Everything appears to be working fine, hot water is good and heating comes on and off as per the programmer and phone app. and I am very pleased with it, (TRV's on radiators).

However, from day one, I have noticed that the water is continually circulating around the heating radiators, i.e. the CH pump runs continuously even when the system is not calling for heat from the boiler. I am not sure if this is normal or not, I initially thought this was down to the way the Wave controller works, as there is no 'off' option in the heating program time segments, you can only set the desired temperature for a specific time period. This means that the pump works continuously day and night, i.e. Even when the thermostat set temperature is less than the actual room temperature, therefore no call for heat from the boiler.

My question is simply, is this normal for this boiler and 'Wave' controller or is there a fault somewhere? I am worried that the continual running of the pump is using a lot electricity and will eventually cause the pump to wear out prematurely. I have just had a look at the boiler fitting instructions and the flow chart would seem to suggest the pump should cut out after 3mins once no call for heat from the system, but I am not sure if this applies in this instance and the 'Wave' controller.

Thanks in advance, James
Sponsored Links
Hi, this isn't a fault, your boiler is working on weather compensation and the pump stays on. If it's annoying you can turn it off but then the weather comp isn't as accurate.

I suggest you ring Worcester tech helpline, they will go through it and explain it a lot better than me.

But don't worry it isn't a problem, the pump can take it and it's running very cheaply for you
hi, has anybody worked out the savings of weather compensation vs not? Taking into account electric power to run pump constantly.
Let's assume pumps last 10 years whatever the case.

In my case, the wave is in a part of the house not heated at night (Honeywell Homexperts on all rads) so I can't rely on its internal thermostat.
Sponsored Links
Apologies for the thread revival, but what's the link between weather compensation being enabled, and continuously pumping water round the system?

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local