K
KevA
Hi,
I have been fault finding on a Heatrae Sadia Electromax combined electric boiler
and domestic hot water supply store. The appliance has a 45A circuit for the boiler
and 16A circuits for the immersion heaters, one circuit is for off-peak (e.g. Economy 7 or 10) and one for normal '24-hour' supply. It appears that the MCB (owner a bit vague) for one circuit has been tripping and a double pole isolating switch shows signs of overheating plus the control circuit board has been damaged. A engineer for the manufacture has been previously called out and said an additional circuit is needed (no report or paperwork to refer to as yet to find out what they mean).
The connection block in the appliance housing has 2 sets of terminals for the 16A circuits and one set for the 45A circuit. When I had a look at the block the 45A circuit is connected OK and there is one 16A circuit connected to the 24-hour supply terminals, 2 links have been added from these terminals to the off-peak terminals (live and neutral). So both immersion heaters are supplied from the 24-hour supply. One immersion heater is labeled 'boost' and the other 'off peak'.
I have read the installation handbook and can't see if this allowed or what the effect of it might be, still trying to get through to the manufacturers technical helpline. I would think that the wiring both heaters (3kW each) to one 16A circuit would cause an overload if both heaters are energised at the same time. But I don't know if both heaters would be used at the same time. Another electrican has been and just replaced the overheated switch and left it at that.
Has anyone experience of working on this model? Just want to be sure I have a good handle on the problem before wastingmy time doing anything that wont make any difference.
Cheers
Kev
P.S. the handbook can be viewed at:
http://www.advancedwater.co.uk/STOMEMO/A016-666-1800/Heatrae Sadia Electromax Installation Guide.pdf
I have been fault finding on a Heatrae Sadia Electromax combined electric boiler
and domestic hot water supply store. The appliance has a 45A circuit for the boiler
and 16A circuits for the immersion heaters, one circuit is for off-peak (e.g. Economy 7 or 10) and one for normal '24-hour' supply. It appears that the MCB (owner a bit vague) for one circuit has been tripping and a double pole isolating switch shows signs of overheating plus the control circuit board has been damaged. A engineer for the manufacture has been previously called out and said an additional circuit is needed (no report or paperwork to refer to as yet to find out what they mean).
The connection block in the appliance housing has 2 sets of terminals for the 16A circuits and one set for the 45A circuit. When I had a look at the block the 45A circuit is connected OK and there is one 16A circuit connected to the 24-hour supply terminals, 2 links have been added from these terminals to the off-peak terminals (live and neutral). So both immersion heaters are supplied from the 24-hour supply. One immersion heater is labeled 'boost' and the other 'off peak'.
I have read the installation handbook and can't see if this allowed or what the effect of it might be, still trying to get through to the manufacturers technical helpline. I would think that the wiring both heaters (3kW each) to one 16A circuit would cause an overload if both heaters are energised at the same time. But I don't know if both heaters would be used at the same time. Another electrican has been and just replaced the overheated switch and left it at that.
Has anyone experience of working on this model? Just want to be sure I have a good handle on the problem before wastingmy time doing anything that wont make any difference.
Cheers
Kev
P.S. the handbook can be viewed at:
http://www.advancedwater.co.uk/STOMEMO/A016-666-1800/Heatrae Sadia Electromax Installation Guide.pdf
