You can raise the F+E tank but the bottom of the F+E should be at the same level as, or preferably below, the bottom of the CWSC, so if raising it will put it above you should raise the CWSC also. Much better to go sealed if you can.
Open CH system but no vent
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You can raise the F+E tank but the bottom of the F+E should be at the same level as, or preferably below, the bottom of the CWSC, so if raising it will put it above you should raise the CWSC also. Much better to go sealed if you can.
Fudge me.............I thought I ha it all sorted till you said that Muggles........why does the expansion tank have to be at the same height as the CWS tank?
Convert to sealed system..........eeerrrr I've not got a clue about how to do that or what the advantages would be?
Convert to sealed system..........eeerrrr I've not got a clue about how to do that or what the advantages would be?
In an ideal world the two water levels should be the same.
The reason being if the header tank is higher than the storage tank, and the coil in the cylinder goes, all the contaminated heating water goes into the potable water and cylinder.
The reason being if the header tank is higher than the storage tank, and the coil in the cylinder goes, all the contaminated heating water goes into the potable water and cylinder.
Wow,there's a lot of tanks in the wrong place!
Having looked at my boiler instructions, the expansion tank only needs to be 6" higher than me boiler (mine is 2foot) BUT, from reading a book, it appears that when a pump starts up, the water level in the feed pipe will drop 3 feet and allow air into the system via the vent pipe. To solve this I assume I need to ensure I have a height of at least 3 feet. Or am I wrong?
Having looked at my boiler instructions, the expansion tank only needs to be 6" higher than me boiler (mine is 2foot) BUT, from reading a book, it appears that when a pump starts up, the water level in the feed pipe will drop 3 feet and allow air into the system via the vent pipe. To solve this I assume I need to ensure I have a height of at least 3 feet. Or am I wrong?
the higher the better
within reason
within reason
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I love sealed systems..Right up to the point where you find the weakness in the existing plumbing... 
Truth is I do prefer sealed systems as they seem to be much easier to bleed the air out of.... Especially on Dorma bungalows...
Truth is I do prefer sealed systems as they seem to be much easier to bleed the air out of.... Especially on Dorma bungalows...
Of course thats true but a faulty coil is rare.
However, the CWST is NOT classed as potable water
Most later systems are pressurised anyway so thats always a risk, in fact a greater risk as the pressure if so much higher.
I have no qualms about raising a F&E tank above the CWST as it usually results in a quieter running boiler and system.
Tony
Yes, but a mains failure resulting in water being drawn down into said mains via a dangling shower head is also rare, but we still use backflow prevention measures to guard against the eventuality. This is just another form of backflow prevention
As for CWSC water not being potable, it isn't in this instance but a correctly-installed modern CWSC used for cold water storage and supply only, seperate from any hot water system, may be classed as potable, provided the CWSC is approved for the purpose of carrying potable water. But let's not get into that debate, I'll end up sounding like trollberk...
Well I am glad if you use a NRV on the supplies to showers because that will prevent callouts to crossover faults.
However, if all you do is fit a ring on the hose so it does not reach the tray contents then it will meet the water regs but can still cause the crossover fault.
I should have said originally that I would only raise the F&E tank when the boiler was fitted only a short distance below. I find that anything less than 1m is to expect problems.
Tony
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