Dunham Bush Chiller

[grump]

London 1999 Dunham Bush Chiller 407C 300kw 2no compressors,discharge pipework 2 1/8

Fault, fracture on this pipework 2n/d 3rd year working
Could not get answers to the problem via the manufacturer.very high frequency vibration from pipework when fully loaded.Approx 2mtr run pipework to air cooled condensing coil.
On the same site is an Airedale air cooled chiller R22 200kw 1 7/8 discharge pipework approx 4mtr run to condensing coil hanging from threaded rod ie allowed extensive movement. Decided to extend pipework on DB chiller to approx 4mtrs.Sometime later one of the coils was replaced the engineer decided to return the discharge pipe work to its original length when a couple months later the pipework fractured followed by a serious malfunction compressor pistons.
I have heard that reciprocating compressors of this duty should not run on 407c please advise , as far as i know its an on going problem,To be continued ie an interesting problem with the Airedale !!!

[nike123]

I think that pipe fracture doesn't have anything to do with fact that R407 is in system.
On the other hand, pipe length, shape, positioning of fixed points and amortization of compressor vibrations (and refrigerant pulses from discharge) has everything to do with fact that pipe frequently break.

[grump]

Nike ,Thank you,the compressors were fitted into such a small space probably to keep the overall size of the chiller down.In the meantime something in the region 400kilos 407 have gone looking for a new home!

[nike123]

You always could fit vibration eliminator.

I already fit this on few chillers, and since then, haven't got any problem with pipes breaking.

http://tinyurl.com/2rn2wd
http://tinyurl.com/2qdmqa

[grump]

Thank you,this i have tried in the past,the ve split down the side approx 75mm.

[nike123]

Thank you,this i have tried in the past,the ve split down the side approx 75mm.
I have difficulty in understanding this part of sentence "the ve split down the side approx 75mm". Pleas, explain.

[grump]

Hi Brainiac.The vibration eliminator burst leaving a split approx 75mm in length. Grump:D

[nike123]

Hi Brainiac.The vibration eliminator burst leaving a split approx 75mm in length. Grump:D

Did you fitted vibration eliminator in parallel with compressor shaft. Other directions are prone to bursts.

[grump]

Hi Nike I am sure it was fitted vertical to the compressor shaft,perhaps you have pinpointed the problem. in the meantime it is no longer my responsibility so will keep your information in mind for future use.
Grump:D:D:D