Can my valiant ecotec run just a single radiator?

Hi all

I'm looking at improving the efficiency of my boiler system. I currently have a valiant ecotec plus 937.

I was thinking of adding some smart TRVs to my radiators so I could switch them on/off independently throughout the day. I will on occasion have just a single radiator running.

I've read about how some boilers have a minimum output requirement. I believe my valiant is around 4.0kw and if this is not met it can lead to short cycling/inefficiency.

If I just have a single radiator running, I would be well under this minimum requirement, as such is it recommended in my case smart TRVs are not recommended (or at the minimum at least a couple should be running at the same time)? Or is there some clever workings in my system that avoids this scenario and having just one radiator on is completely fine?

Many thanks and apologies for my lack of understanding, been learning as I go .

Many thanks

Zee

I think the older type 937 have a minimum output of ~ 12kW, enough to satisfy the max whole house heating requirement for many, if so. 12kw minimum, then not a hope IMO of running it, economically or otherwise, with one rad in circuit.

zuber ali said:

I've read about how some boilers have a minimum output requirement. I believe my valiant is around 4.0kw and if this is not met it can lead to short cycling/inefficiency.

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Any boiler can run just one rad but yes it will lead to short cycling and be highly inefficient.

Madrab said:

Any boiler can run just one rad but yes it will lead to short cycling and be highly inefficient.

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I would suggest that getting a, say, single 2kW rad to operate properly with a 37kW Vaillant is a challenge, to say the least. The boiler will refire (or fire) at ~ 65% of its max output, 37*65%, 24kW and the flowtemp must be kept below the targettemp+5C for up to a minute to avoid the boiler tripping before it modulates down, if the targettemp is 60C then, at a flowrate of say 10LPM, the flowtemp must be reduced to 30/31C to avoid it exceeding 65C on refiring and preferably reduced to 25/26C to avoid it exceeding 60C on refirnig, be interesting to see.

I’m not sure your plan will work on what you wish to achieve. Maybe just invest in smart TRVs and or controls, range rate and reduce trv temp settings.