burst pipework explosion with pics

[silentbobt]

My boss has emailed me pics of a coil that has exploded at 1 of our sites in England.

The “blown” pipe is in the condenser coil on the discharge side of the compressor, it would appear that the HP switch may have failed and caused the condensing unit to run whilst in a high pressure condition, I would have expected the compressor to fail before the pipework, but it is an extremely old system.

Has anybody any other views / ideas on the cause of this?

Thanks in advance
Rob

The pics :

[Tiesse]

Is there not any safety valves etc?

[silentbobt]

Is there not any safety valves etc?

I havent seen the system myself just a few pics from the boss asking for my opinion as we have a few more similar systems across the estate my company is responsible for maintaining.

[multisync]

This looks like a daikin?

We have got a couple of these and the motor frams is very poor and distorts. This leads to the belts shredding and either going very loose or shedding completely.

I have seen loads and loads of systems running without condenser cooling -either from the above or a faulty fan motor etc- and not seen an 'explosion' like that. Most compressors would usually lift their internal release valve before then.

The first picture looks like it's been kicked in rather than blown out.

[desA]

What was this attached to?
What refrigerant was in the system?
The piping looks pretty thin-walled...

[Shibhrac]

I don't think a faulty high pressure switch could make refrigeration system ends with an explosion in the event of condenser fan motors failurs.usually compressor relief valve releases the pressure if the pressure increased up to the 450 psi and as compressor temp. getting high the thermall protecter will react to safe the compressor. I would only assume that the said explosion was a result of accessive pressure being put to the system. Like using unregulated nytrogen in the event of pressure leak testing.

[Brian_UK]

Looks like the end of a spun filter.

[Tesla]

Looks like more than one safety failed here. Just guessing it was possible that the system was excessivly overcharged. Asides the HP were any other faults found?

[Magoo]

Looks like a serious screw-up on someones part, agree with Brian_UK that system overcharged. Possibly installed by a non-refrig tech.

[desA]

Looks like the end of a spun filter.

That's what I wondered. This has then torn itself apart, & the pipe has wrapped back to clout the condenser from the outside - hence the external fin damage.

Mmmhhh...

[Tesla]

When I was much younger and still learning, I was working on a system with a blocked TEV and assumed it was short of gas - so I started putting more and more gas in. Luckily I had high and low gauges fitted. I noticed in about 10 seconds the HP gauge went to the end of the scale. I quickly turned unit off and relieved some pressure from the high side. It was like a hydrostatic pressure build up. Very very lucky. We learn by our mistakes. With the other units on site where the one above had an explosion it would be prudent to remove gas from a few of them to check charge by weight. Also find out ( if overcharged) who did it and educate that person.

[multisync]

I'm guessing here but I suspect it's lost it's gas charge by now so the chances of getting anyone to either admit they did or worse actually know they overcharged it and kept carrying on is unlikely in the extreme.

I think we need to know at what stage did this happen.Was it during normal operation, without an engineer being present, or during some repairs. More info needed for sure

[Contactor]

Someone has been doing hot work in the last picture, maybe they changed the fan motor and damaged the coil in the process, bodged a repair together, and then later the repair blew.

[Prince Vaillant]

If its on R410 it could be the copper wasn't suitable for the job too.

[littleyapper]

i would tend to agree with contactor... last guy at it seems to have hit the condensor also i dont think that unit is designed to be ducted .. there for higher heads etc etc

[NoNickName]

No way a compressor can burst a pipe on vapour compression. It can only happen for liquid hit or improper nitrogen testing.

[multisync]

i would tend to agree with contactor... last guy at it seems to have hit the condensor also i dont think that unit is designed to be ducted .. there for higher heads etc etc

Why do you think they are not designed for ducting?