Banging Pipes

[perfexa]

Hello all,

I require your help and support to get to the bottom of this issue.

I've always had banging pipes in my property however I do think it's getting worse. Initially when the boiler starts to heat the radiators and hot water tank they bang very loud and fast for a few moments. All is practically then quite until the hot water tank has been heated (approx 40 mins) and then switches over to just heating the radiators around the house.

Once the boiler is heating the house radiators throughout the whole process the pipes will bang in one location of the house, my theory is that the pipes are expanding and knocking, I did turn the boiler right now to a lot cooler temperature will did help, however as a result it does not heat the property.

That said I can't understand why when the boiler is heating the radiators and the tank its practically silent, even the banging pipes, does it use a different loop in the system, or could it be that the grundfoss pump pressure is too high?

I've tried auto adapt on the pump, again that helps a very small amount but the pipes still bang, I'm at a total loss with this system.

• 5 radiators (small property)
• 1 new boiler
• 1 hot water tank
• 1 grundfoss alpha 2 pump

Anymore info require please let me know

 

[Aquarius]

Do you have a 3 port mid position valve? Could be this that’s the issue, also check the feed and expansion tank has got water in it.

 

[perfexa]

Do you have a 3 port mid position valve? Could be this that’s the issue, also check the feed and expansion tank has got water in it.

Hi, yes I do have a 3 port mid position valve, I'm a rookie with plumbing so an education may help me to the cause of these horrible problems

 

[ShaunCorbs]

Is it banging or more of a creaking noise ?

 

[perfexa]

Is it banging or more of a creaking noise ?

Banging all the time

 

[ShaunCorbs]

Does the pump display light up ?

 

[perfexa]

Does the pump display light up ?

Yes, currently my heatings not on, so it's not lit up. Pump has many features its a grundfoss alpha 2

 

[ShaunCorbs]

It could be the pumps getting on its last legs And could be working on gravity circulation when the cylinder is heating hence less noise but when it’s heated the cylinder up the banging comes back as the pump can’t get the heat away fast enough/ at all

maybe

 

[perfexa]

It could be the pumps getting on its last legs And could be working on gravity circulation when the cylinder is heating hence less noise but when it’s heated the cylinder up the banging comes back as the pump can’t get the heat away fast enough/ at all

maybe

The pump is only about 1-2 years old, so its new still, the gas engineers put it on pump speed two which I think is fairly high given the size of the house, but then again I'm no engineer, I'm at a loss on this one

 

[Aquarius]

Once system is cold, turn off switch next to programmer, check in cylinder cupboard that the mid position valve (the Drayton on you showed in the photo) has gone back to w. Once this has happened, select hot water on only, and check if the banging is the same, less, or non existent.

 

[perfexa]

Once system is cold, turn off switch next to programmer, check in cylinder cupboard that the mid position valve (the Drayton on you showed in the photo) has gone back to w. Once this has happened, select hot water on only, and check if the banging is the same, less, or non existent.

when it heats the hot water tank it switches to M on the mid position valve, I've never seen it go onto W

 

[Aquarius]

when it heats the hot water tank it switches to M on the mid position valve, I've never seen it go onto W

This could be your issue then. If it is then it’s either the actuator (motor inside the head of valve) or the valve itself, which could be sludge or debris etc.

 

[perfexa]

This could be your issue then. If it is then it’s either the actuator (motor inside the head of valve) or the valve itself, which could be sludge or debris etc.

Is there a way I can move it to the W position manually? As I’m a rookie and seeking advice from people on the forum who are qualified and experts can someone explain what the letters mean / do on the valve, I’ve got a basic idea

 

[John.g]

Is there a way I can move it to the W position manually? As I’m a rookie and seeking advice from people on the forum who are qualified and experts can someone explain what the letters mean / do on the valve, I’ve got a basic idea

Speed 2 on that pump is 3M which shouldn't be too high, also if its the model I think it is, it displays watts which is a very useful guide, if so, can you note them (watts) on CH only, on both CH&HW and on HW only, and also check the operating mode/speed setting.

Think it may also display the flow in M3/hr, you might also note this as well as the power.

 

[Aquarius]

Is there a way I can move it to the W position manually?

I’m not sure there is. However, what could be done is, remove the motor head, there’s x2 plastic push-in retainers, push these in, and head should come off. This would enable you to check the spindle moves freely by hand, also you could then call for a heat up of heating and hot water and see if the noise still exists. Getting the head of the valve back on needs to be precise though.

 

[Warmiger]

Had this a few times. I would go with a faulty 3 port. Arm is swinging back and forth or the ball has come away.