My Valiant combi-boiler makes an awful lot of noise whenever it starts up. The heating is fine, no other complaints, but it means I have to turn the heating off on winter nights to ensure a full night's sleep. I've been living with this for ages, as I've yet to find an answer online, and also because I am financially allergic to calling a technician. I thought I'd ask here for some general opinions before trying to talk to a technician (I'm living in The Netherlands, and while everyone here speaks English, I'd still prefer to have some ideas before going into the discussions).
The boiler is connected to a 4-hose in-floor central-heating system in a small ground-floor apartment. The system was three years old when I bought the apartment 5 years ago; the problem was noticeable from the first night.
Without resorting to musical notation, here's a description of the symptoms:
1. At the required room temperature, the system switches on.
2. Sound of a low hum that rises for about 5 seconds as the system "revs up", and the gas ignites.
3. After ±5 seconds, the hum and accompanying ignition noises return to the lower pitch as the ignition sequence "revs down".
4. This is followed by a series of much louder low moans from the boiler itself. The moans are a uniform pitch (somewhere around an octave below middle C), with a slow "throbbing" attack. Its tone sounds like someone is playing a trombone or, as another forum post described it, blowing over a large plastic milk jug. The period of each "throb" varies, as does the volume. Sometimes, the throbbing quickens, while its volume decreases, until all is still and quiet. At other times, the throbbing just slows down until all is quiet. The duration of this little concert varies as well, but it normally doesn't last more than 30 seconds or so.
5. It appears that the intensity and longevity of the noises are related to the temperature. If I've had the heat turned right down for a few days, and the room temperature is below 15°C, the moaning is positively otherworldly and it takes longer to quiet down. If I leave the thermostat at 21°C, and the room temperature merely drops enough to trigger the system, it is less noisy. (That said, it is certainly loud enough to wake me from my sleep at 3 in the morning, so I have to turn the thermostat way down each night to avoid being awakened.)
I have not read of too many others with the same problem, so I've only tried bleeding the system (for which, I'm afraid there are few guides online pertaining to an in-floor heating setup), and changing the speed of the pump motor. Neither of these have had any effect.
Perhaps I am not bleeding the system properly? I can't find any instructions for bleeding a 4-hose under-floor system, so if anyone can instruct me there, I'd appreciate it.
That said, the noise doesn't appear to be coming from the hoses or from the pump, but from the boiler itself. I've never been able to localize it any more precisely. While it seems like the whole unit is trumpeting, it could possibly be more intense from somewhere on the top right.
Any thoughts?
The boiler is connected to a 4-hose in-floor central-heating system in a small ground-floor apartment. The system was three years old when I bought the apartment 5 years ago; the problem was noticeable from the first night.
Without resorting to musical notation, here's a description of the symptoms:
1. At the required room temperature, the system switches on.
2. Sound of a low hum that rises for about 5 seconds as the system "revs up", and the gas ignites.
3. After ±5 seconds, the hum and accompanying ignition noises return to the lower pitch as the ignition sequence "revs down".
4. This is followed by a series of much louder low moans from the boiler itself. The moans are a uniform pitch (somewhere around an octave below middle C), with a slow "throbbing" attack. Its tone sounds like someone is playing a trombone or, as another forum post described it, blowing over a large plastic milk jug. The period of each "throb" varies, as does the volume. Sometimes, the throbbing quickens, while its volume decreases, until all is still and quiet. At other times, the throbbing just slows down until all is quiet. The duration of this little concert varies as well, but it normally doesn't last more than 30 seconds or so.
5. It appears that the intensity and longevity of the noises are related to the temperature. If I've had the heat turned right down for a few days, and the room temperature is below 15°C, the moaning is positively otherworldly and it takes longer to quiet down. If I leave the thermostat at 21°C, and the room temperature merely drops enough to trigger the system, it is less noisy. (That said, it is certainly loud enough to wake me from my sleep at 3 in the morning, so I have to turn the thermostat way down each night to avoid being awakened.)
I have not read of too many others with the same problem, so I've only tried bleeding the system (for which, I'm afraid there are few guides online pertaining to an in-floor heating setup), and changing the speed of the pump motor. Neither of these have had any effect.
Perhaps I am not bleeding the system properly? I can't find any instructions for bleeding a 4-hose under-floor system, so if anyone can instruct me there, I'd appreciate it.
That said, the noise doesn't appear to be coming from the hoses or from the pump, but from the boiler itself. I've never been able to localize it any more precisely. While it seems like the whole unit is trumpeting, it could possibly be more intense from somewhere on the top right.
Any thoughts?
