Hi all.
Long one but I might as well try and give you all the info in one post.
I had a new Vaillant ecofit combi boiler fitted last year. It was only powering two radiators due to our renovation being early stages, I’m not sure if he adjusted any settings to ensure this was fine with the boiler. We now have six radiators, although sometimes we turn off one or two in spare rooms if they’re not being used. The radiators have older style manual valves.
Generally we turn on the heating at 5pm and the room would be up to target temperature of 18.5 within an hour. Excellent. I noticed that the boiler was still turning on every once in a while between say 7 and 10pm, even though the thermostat said 18.5 still. It was only costing 10p an hour but it seemed completely pointless if the radiators were barely lukewarm. The house seems to be holding the heat fairly well.
I sat and watched the boiler once up to room temp and the flow temp would be at 39, the boiler would fire up for 30 seconds, it would go to 45 and it would anti cycle. Completely pointless and I can’t understand why it would be calling for heat and only leave it on for 30 seconds.
I had a look at the flow temperature on the boiler and this was set to 75, which seemed stupidly hot, so I’ve now set that to 65, but nothing really changed. I remember him saying it had to be hot with only two radiators on the system.
I tried setting the thermostat to 19.5 and this seemed to work more like how I’d expect the system to work, in that it was cycling on and off while keeping the radiators at a more consistently higher temp. Only issue was that it seemed to be cycling every 5 minutes, which seems far too often.
Could it be a case that the anti cycle time has been set to 5 minutes and this would be better set to at least 10 mins. I’m not sure it explains why the boiler clicks on for only 30 seconds when the flow temp is only 45.
Any advice would be appreciated.
Long one but I might as well try and give you all the info in one post.
I had a new Vaillant ecofit combi boiler fitted last year. It was only powering two radiators due to our renovation being early stages, I’m not sure if he adjusted any settings to ensure this was fine with the boiler. We now have six radiators, although sometimes we turn off one or two in spare rooms if they’re not being used. The radiators have older style manual valves.
Generally we turn on the heating at 5pm and the room would be up to target temperature of 18.5 within an hour. Excellent. I noticed that the boiler was still turning on every once in a while between say 7 and 10pm, even though the thermostat said 18.5 still. It was only costing 10p an hour but it seemed completely pointless if the radiators were barely lukewarm. The house seems to be holding the heat fairly well.
I sat and watched the boiler once up to room temp and the flow temp would be at 39, the boiler would fire up for 30 seconds, it would go to 45 and it would anti cycle. Completely pointless and I can’t understand why it would be calling for heat and only leave it on for 30 seconds.
I had a look at the flow temperature on the boiler and this was set to 75, which seemed stupidly hot, so I’ve now set that to 65, but nothing really changed. I remember him saying it had to be hot with only two radiators on the system.
I tried setting the thermostat to 19.5 and this seemed to work more like how I’d expect the system to work, in that it was cycling on and off while keeping the radiators at a more consistently higher temp. Only issue was that it seemed to be cycling every 5 minutes, which seems far too often.
Could it be a case that the anti cycle time has been set to 5 minutes and this would be better set to at least 10 mins. I’m not sure it explains why the boiler clicks on for only 30 seconds when the flow temp is only 45.
Any advice would be appreciated.
