I have a Loblich (Austrian make you probably never heard of) 35 kW wall mounted gas Combi boiler/hot water heater. The unit is three years old, the heat exchanger was replaced 2 months ago as it was leaking. Now it has a new fault and I need some ideas as Loblich say it’s the pipes and my plumber says it’s the boiler.
There is a fairly loud rattle coming from the heat exchanger. It sounds like an erratic car engine with worn tappets at idle. It’s infrequent, but here are some points I can tell you:
- it’s definitely not a lose part of the casing or anything like that, although it sounds like it. The noise comes from inside the heat exchanger.
- when the gas is burning the noise almost always goes away.
- I can continuously recreate the rattle by turning off the gas and have the central heating water circulate through the boiler, even when the water is cold. While it’s doing this, if I turn on the hot tap, the noise goes away totally while the water is running.
The water pressure is about 1 bar, I’ve tried different pressures, bled the radiators and the pump, but still the same rattle.
Any ideas would be most appreciated
Thanks in advance
Chris
There is a fairly loud rattle coming from the heat exchanger. It sounds like an erratic car engine with worn tappets at idle. It’s infrequent, but here are some points I can tell you:
- it’s definitely not a lose part of the casing or anything like that, although it sounds like it. The noise comes from inside the heat exchanger.
- when the gas is burning the noise almost always goes away.
- I can continuously recreate the rattle by turning off the gas and have the central heating water circulate through the boiler, even when the water is cold. While it’s doing this, if I turn on the hot tap, the noise goes away totally while the water is running.
The water pressure is about 1 bar, I’ve tried different pressures, bled the radiators and the pump, but still the same rattle.
Any ideas would be most appreciated
Thanks in advance
Chris