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7th November 2019, 07:11 | #1 |
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Any gas fitters?
Our Bali netatec has been a pile of $¥1t since new, we have had Bali out about 6 times in the last 12 months for one fault after another, mainly due to no hot water, or heating. Now the pressure drops to rock bottom, so I top it up to within the requisite parameters, within an hour it reaches too high a pressure, drain a little from the radiator to reduce the pressure, I’m talking a couple of eggcup full, and within 30 minutes it drops too low. Any ideas?
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7th November 2019, 09:54 | #2 |
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You have a leak. As the heating heats the pressure will increase and then drop as it cools. Does the boiler have a pressure release valve, if this has given up (become weak) it could be allowing water to escape to the drain or the outside
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7th November 2019, 10:23 | #3 | |
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Quote:
Not strictly true as being a combi boiler it should have an expansion tank. As the water heats up it pushes water in the expansion tank and as it cools it pushes it back into the system. There will be some pressure variation but nothing like if there was no tank. |
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7th November 2019, 12:04 | #4 | |
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Quote:
macafee2 |
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7th November 2019, 12:37 | #5 |
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All sealed systems will have an expansion vessel. Generally speaking it will have a diaphragm across the middle of it and one side will be air and the other water. If this fails and it all becomes full of water then when the system water is heated it will have no where to expand to (by compressing the air) this will cause the pressure relief valve to open and when the water cools there is low water in the system.
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7th November 2019, 15:28 | #6 | |
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There may of course be an independent leak, which could be a joint out of sight ( a nightmare) or at the radiator valves or a bleed screw not sealing macafee2 |
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15th December 2019, 14:19 | #7 |
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Tie a plastic bag over the emergency pressure relief valve outlet (short copper pipe, should be outside). Then you can see if it is coming out of there.
If it isn't the vessel, then do you have a leak somewhere on your heating or cylinder pipework? Sent from my Redmi 4X using Tapatalk |
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