Tubular heaters - corrosion at terminals

[ringer]

One of the jobs I am doing at a church is looking at tubular heaters - some of them are not working. Tubes are single or in vertical columns of three or four, running in the pews. Being in a church they are typically turned on once a week for a few hours, winter time only.

The ones that are not working show severe signs of corrosion where the flex joins the heater terminals. Where they are banked vertically, it is only the bottom one where the flex is connected where there is corrosion. Typically only one terminal is corroded, the other is fine. Wires from the flex have turned green and snapped (one terminal only), and the terminal itself has signs of corrosion too. Heaters that are still working appear to be relatively unaffected by corrosion at the terminals.

The obvious solution to this is to clean up the terminals affected, providing they are not too badly corroded, and fitting a new flex, but I would like to determine why this corrosion has occurred so that it may be prevented in future. Any advice on precautions that can be taken?

 

[mogga]

during cold damp months Condensation will build up in steel which is cold hence moisture will cause corrosion specialy over the years

 

[Phil]

i got a batch of them a couple of years ago. seen about twelve months out of them before they were no good. one i plugged in started smoking straight away and didn`t smell too good. trouble is where he wanted them mounting against my advice they were used as foot rests

 

[nickblake]

yes had the same problem at a church ,and to be honest the amount of time you spend fixing the things it works out cheaper to replace them and as phil if they are under the pews then put a guard over them , down side to doing that is the guards cost more than the heaters