Source Low Fogger Blows Thermal fuse

[Don Allen]

I recently repaired a Source Low Fogger (seemed to be a copy of the Antari Ice) that was tripping rcd's. Visual checks showed up whisps of smoke coming from rear hole in heater block with no smoke output even though fan was running and fluid pump running.

 

Stripped heater because spares are sparse in Australia, cleared out with compressed air, reassembled and when trying to test found that thermal fuse had blown. Replaced with same 192 degree thermal fuse fuse from RS and unit ran fine for ten minutes. No sign of smoke coming from rear hole in heater block.

 

Unit was sent to rehearsals for soak testing and has stopped working again, as has second Source Low Fogger, so assume thermal fuse has blown.

 

Anyone have any suggestions why ? as I assume that the heater should normally be capable of running continuously as there is no controller on it, it is connected across the mains, after the mains switch.

 

Thanks

Don

[Don Allen]

I found the fault on these units and it may help someone.

 

The units are fitted with 250 volt MOV's which were breaking down due to high mains volts of 250 volts and fluctuating higher. Have fitted units with 275 volt MOV's which are the standard MOV's that Altronics carry in West Australia because of our high mains volts. (meant to be 240v). A gen-set running high could cause similar fault.

[cedd]

Funnily enough we lost 2 of these units on the same night of "carousel" last week. Both had popped their local fuse and are now refusing to work full stop. I'll pass those details on to the guy that's taking a look at them.

Both were on the same supply with the same duty cycle, same age and same conditions. Didn't think it could be the same fault on both at exactly the same time, but perhaps a blip on the mains was enough.

The great design flaw is that when the unit has died, the pump won't operate to drain the unit down so it has to be lifted out full of water - believe me, you get very wet!

 

Many thanks for that!