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Geoff
09-04-2004, 07:15 PM
Hi, I hope someone (Terry?) can answer my question as this is driving my family nuts.

I have a new hydronic heating system and while it heats the house very well, every 30 secs there is a loud tapping noise coming (presumably) from pipes in the ceiling. I can hear it about 5 secs just after the boiler ignites. The noise is not coming from the boiler. My house is 2 storey and uses radiators and fan type radiators. The boiler is a Hurlcon H150S. It does have a little LCD panel on the side where the water temp can be set and I've set it to 75 deg C. I've also set the pressure in the boiler to 2 bar. The web address for the boiler if you'd like to see what it looks like is: http://www.hurlcon.com.au/manuals/H120-150%20Boiler%20136-0803.pdf

I've bled the radiators for air and there isn't any in them.

I'm wondering if the plumber forgot to add a part to the system? I have to turn off the boiler at night because we can't get to sleep but then we get cold...

Does anyone know what I can do about this problem?

--Geoff

hj
09-05-2004, 07:05 AM
Find where the pipes are attached too tightly and are "scraping" as they heat and expand.

e-plumber
09-05-2004, 09:51 AM
Depending on how long ago the system was installed, why not call the installer and have him/her correct it?

The tapping is from heating line piping passing through a very tightly drilled hole or notch or possibly wedged in a tight area. The tapping or slight knocking is expansion in the lines when hot water is circulating it, it is a common occurance.

Geoff
09-05-2004, 04:50 PM
Thanks for the replies!

Unfortunately the heaters are attached to the existing old pipes which the plumber didn't install so I guess I'll have to cut into the ceiling & have a look myself.

Which leads me to the next question, presuming I can locate the tight spot & can chisel out the timber, how do I attach the pipe if I find that it's loose? With a u shaped Terry clip or is there a special clip I need to use? Should I put rubber under the affected area of pipe?

--Geoff

Geoff
09-06-2004, 03:53 AM
Thanks for the replies!

[snip]
Which leads me to the next question, presuming I can locate the tight spot & can chisel out the timber, how do I attach the pipe if I find that it's loose? With a u shaped Terry clip or is there a special clip I need to use? Should I put rubber under the affected area of pipe?

--Geoff

I think I've found the answer, thanks to the "Water pipe movement" thread of a few days ago. I'll buy some copper straps. Thanks to Jimbo for the tip.

Gee this is a great site!

Regards,
Geoff

jadnashua
09-06-2004, 08:14 AM
you can buy perforated plastic strapping. Might want to consider that - metal on metal scraping vs sliding in the plastic. If you need to keep it more rigidly anchored, then metal is better, but if you just need it to say center going through a hole, the plastic may be better.

Geoff
09-09-2004, 04:33 PM
Ok, thanks for that. I 'll try the plastic first and if there's no improvement then I'll use copper.

--GD