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UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
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#1
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Hydronic Open-Vented Central Heating System
Hi
Last weekend the overflow to the expansion tank started to drip. I took a look at the tank and manually reduced the water level in the tank. I was expecting to find the ball-valve feed dripping and needing to be replaced - but it wasn't. Over the last few days the water level in the tank has risen around 1", so I presume that water is returning via the expansion pipe. Could someone expand on what the possible causes are? Thanks |
#2
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Hydronic Open-Vented Central Heating System
In an earlier contribution to this discussion,
Denny wrote: Hi Last weekend the overflow to the expansion tank started to drip. I took a look at the tank and manually reduced the water level in the tank. I was expecting to find the ball-valve feed dripping and needing to be replaced - but it wasn't. Over the last few days the water level in the tank has risen around 1", so I presume that water is returning via the expansion pipe. Could someone expand on what the possible causes are? Thanks I assume that you have 2 tanks in your attic - a large cold water header tank for the HW system, and a smaller fill and expansion tank for the primary circuit? I assume that it's this smaller tank with which you have the problem? I assume further that the water level in the large cold header tank is higher than that in the small F&E tank? If these assumptions are correct, I fear that you need a new hot water cylinder. The HW cylinder has an internal coil/heat exchanger through which water heated by the boiler passes, heating the domestic hot water without mixing with it. BUT, if this coil springs a leak, the primary and secondary circuits *do* mix - causing water from the higher tank to flow into the lower tank. -- Cheers, Roger ______ Email address maintained for newsgroup use only, and not regularly monitored.. Messages sent to it may not be read for several weeks. PLEASE REPLY TO NEWSGROUP! |
#3
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Hydronic Open-Vented Central Heating System
"Roger Mills" wrote in message ... In an earlier contribution to this discussion, Denny wrote: I assume that you have 2 tanks in your attic - a large cold water header tank for the HW system, and a smaller fill and expansion tank for the primary circuit? I assume that it's this smaller tank with which you have the problem? I assume further that the water level in the large cold header tank is higher than that in the small F&E tank? If these assumptions are correct, I fear that you need a new hot water cylinder. The HW cylinder has an internal coil/heat exchanger through which water heated by the boiler passes, heating the domestic hot water without mixing with it. BUT, if this coil springs a leak, the primary and secondary circuits *do* mix - causing water from the higher tank to flow into the lower tank. -- Cheers, Roger All your assumptions are correct - Thanks for the clear explanation Roger |
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