plumbing exam help

[ldpooley]

I've recently done a mock test for a plumbing exam and wasnt happy with some of the answers given by the tutors, can any of you more knowledgeable plumbers give me your opinions on the following:

1.what is required soundness test pressure for hot water pipework which is normally subject to static head pressure of 6 metres?
a.1.2 bar b.0.9 bar c.0.6 bar

which of the following can be fitted to a hot water storage cylinder to provide protection against type 1 pitting corrosion?
a. pressure reducing valve b. magnetic conditioner c.sacrificial anode

what backflow protection device should be fitted to mixer tap fed with from cold mains that permits mixing of hot and cold water in valve body
a.double check valve b.single check valve

during soundness testing on an open vented hot water system ?
a. cold feed gate valve should be opened b.open vent pipe should be capped c.two taps should be opened

i went with b. c. b. and b. but was given other answers,so confused

 

[Tay7]

Acaa

 

[picasso]

I would have gone for

b 0.9

c sacrifical anode

b single check

b open vent capped

so not sure what answers they want ?

 

[ldpooley]

cheers picaso exactly the same as my answers, however tutor has given answers completely different

 

[Dan Robinson]

I'm with @Tay7 on this one.

 

[picasso]

soundness testing is normally carried out at 1.5 x normal working pressure 0.6 x 1.5 = 0.9 so why would 1.2 be the answer ?

single check valves are ok unless the airgap is not sufficient , so why double check valves ?

last one not sure.

 

[Newboy]

single check valves are ok unless the airgap is not sufficient , so why double check valves ?

No airgap

 

[picasso]

You would find it difficult to find a tap with no airgap above the spill over level.

 

[Dan Robinson]

Mixing in the body .

 

[TCCHeating]

You would find it difficult to find a tap with no airgap above the spill over level.

Not that difficult mate

 

[picasso]

Thought we were talking about standard mixer taps? Those taps would need double check only because the head goes lower than the spill over level, a standard mixer tap even those that mix in the body only need single check valves ,

 

[PullerGas]

I've recently done a mock test for a plumbing exam and wasnt happy with some of the answers given by the tutors, can any of you more knowledgeable plumbers give me your opinions on the following:

1.what is required soundness test pressure for hot water pipework which is normally subject to static head pressure of 6 metres?
a.1.2 bar b.0.9 bar c.0.6 bar

which of the following can be fitted to a hot water storage cylinder to provide protection against type 1 pitting corrosion?
a. pressure reducing valve b. magnetic conditioner c.sacrificial anode

what backflow protection device should be fitted to mixer tap fed with from cold mains that permits mixing of hot and cold water in valve body
a.double check valve b.single check valve

during soundness testing on an open vented hot water system ?
a. cold feed gate valve should be opened b.open vent pipe should be capped c.two taps should be opened

i went with b. c. b. and b. but was given other answers,so confused

1.5 times the working pressure.
DCV
Open vent should be capped. I don't think a Gatevalve would hold .9bar test.

 

[picasso]

wait

 

[picasso]