Can anyone suggest a solution or help?
When my timer starts both heating and hot water, there are two motorised valves (one for hot water and one central heating) there is No noise from the pipes. However, when the hot water reaches temp and switches the motorised valve off the noise starts! It sounds like a kettle and is loud. Difficult to pinpoint where but sounds more from the return Pipework. The noise stops if I manually push the lever on the hot water motorised valve to open. Close it again and the noise begins. Hot water only on and there is no noise. So I can deduce the noise is from the central heating not hot water. I just changed the heating motorised valve which didn't help. I bled the system no benefit (the water was clear coming out). Inhibitor added annually. I opened all the Trvs and lock Sheilds no luck. Varying the pump speed has no effect. The pump sounds ok. Grunfoss and only 6 years old. The expansion vessel is correct pressure. The system heating is fine and running at 1.5 bar. All radiators have bidirectional valves fitted. All radiators are fairly new staggered fitting in last 6 years. 11 rads and 2 towel rails. New Worcester condensing boiler fitted 3 years ago. Can't pinpoint when or any specific change that started this but the noise is driving us mad!
When my timer starts both heating and hot water, there are two motorised valves (one for hot water and one central heating) there is No noise from the pipes. However, when the hot water reaches temp and switches the motorised valve off the noise starts! It sounds like a kettle and is loud. Difficult to pinpoint where but sounds more from the return Pipework. The noise stops if I manually push the lever on the hot water motorised valve to open. Close it again and the noise begins. Hot water only on and there is no noise. So I can deduce the noise is from the central heating not hot water. I just changed the heating motorised valve which didn't help. I bled the system no benefit (the water was clear coming out). Inhibitor added annually. I opened all the Trvs and lock Sheilds no luck. Varying the pump speed has no effect. The pump sounds ok. Grunfoss and only 6 years old. The expansion vessel is correct pressure. The system heating is fine and running at 1.5 bar. All radiators have bidirectional valves fitted. All radiators are fairly new staggered fitting in last 6 years. 11 rads and 2 towel rails. New Worcester condensing boiler fitted 3 years ago. Can't pinpoint when or any specific change that started this but the noise is driving us mad!