hi guys if any 1 could help me out with a few question applying for job as some ques aint clear to me anyway
1. what is maximum length of twin walled chimney pipe manufactured to BS715 that can be run externally? the answer would be not allowed because gas appliances should not be installed on metal twin wall..... or is the ans its not exceed 3meters
2. a ventilator that is fitted with a fly screen would be categorized as? NCS if the appliance is working fine
3. The most likely cause of the domestic water being too hot from a combination boiler could be? don't get this ques 1. its combi so the problem would either be thermostat on the boiler, thermistor
A.Thermostat is set too low
B.Airflow switch is defective
C.Blocked or scaled heat exchanger
D. pump speed is too high
i would select (C) but im thinking boiler would over heat and cut out or you would get hot then cold then hot n so on )
4. The customer complains of no hot water. This problem could be cured by? dont get this is the room stat working, 3port working, cylinder stat working
A.Fitting a variable speed pump
B.Fitting an anti-gravity valve on the central heating flow
C.Fitting an automatic air-release on the Primary flow
i would think logical its (C) to get rid of trapped air ???
5. do you have to do a final Earth continuity check? if uve done it, at the start cos people tell me they don't need to do a final check but i would think you have to ensures protection if a fault occur at a later date
if any one could help or explain more pls do
1. what is maximum length of twin walled chimney pipe manufactured to BS715 that can be run externally? the answer would be not allowed because gas appliances should not be installed on metal twin wall..... or is the ans its not exceed 3meters
2. a ventilator that is fitted with a fly screen would be categorized as? NCS if the appliance is working fine
3. The most likely cause of the domestic water being too hot from a combination boiler could be? don't get this ques 1. its combi so the problem would either be thermostat on the boiler, thermistor
A.Thermostat is set too low
B.Airflow switch is defective
C.Blocked or scaled heat exchanger
D. pump speed is too high
i would select (C) but im thinking boiler would over heat and cut out or you would get hot then cold then hot n so on )
4. The customer complains of no hot water. This problem could be cured by? dont get this is the room stat working, 3port working, cylinder stat working
A.Fitting a variable speed pump
B.Fitting an anti-gravity valve on the central heating flow
C.Fitting an automatic air-release on the Primary flow
i would think logical its (C) to get rid of trapped air ???
5. do you have to do a final Earth continuity check? if uve done it, at the start cos people tell me they don't need to do a final check but i would think you have to ensures protection if a fault occur at a later date
if any one could help or explain more pls do