15 mm feeding in
three port valve (which is sticking)
22mm expansion with 5m pump head up its ja***ie
three port valve (which is sticking)
22mm expansion with 5m pump head up its ja***ie
Water shoots out over overflow when boiler starts
- Thread starter Oldone
- Start date
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The water can only come to the f& e in through 3 routes.
1--mains inlet controlled by float valve
2--vent pipe over cistern
3--back up from cylinder via feed pipe.
If the cylinder coil (heat exchanger) has split, water can enter in (or out depending on which has the greater pressure).
This 'extra' water has to go somewhere and will follow the path of least resistance.
If the water is leaking into the coil the level of f&e water will rise and overflow
1--mains inlet controlled by float valve
2--vent pipe over cistern
3--back up from cylinder via feed pipe.
If the cylinder coil (heat exchanger) has split, water can enter in (or out depending on which has the greater pressure).
This 'extra' water has to go somewhere and will follow the path of least resistance.
If the water is leaking into the coil the level of f&e water will rise and overflow
BACHO I can see the logic in your explanation completely.
KEV even if the valve is sticking I still can't see how this would cause pumping over unless it had been a problem from when the system was first commissioned. In what position could the valve stick to cause such high pressure in the vent pipe. Plus even if it were pumping over, this should not alter the total volume of water in the heating circuits.
Still, if replacing the three port valve has cured the problem, I must be missing something.
KEV even if the valve is sticking I still can't see how this would cause pumping over unless it had been a problem from when the system was first commissioned. In what position could the valve stick to cause such high pressure in the vent pipe. Plus even if it were pumping over, this should not alter the total volume of water in the heating circuits.
Still, if replacing the three port valve has cured the problem, I must be missing something.
dosent have to cause high pressure just restrict the flow enough as bahco said it takes the path of least resistance
btw bahco check your e mail
btw bahco check your e mail
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I'd still love to know why the F&E (CH header tank) cistern is overflowing if it is not the ball valve. Sorry if I am being thick here, I still don't understand the cause of the overflow.
My view is the water lever in the tank is too high and the excess water in from the expansion is filling the tank past the overflow level and overflowing.
My view is the water lever in the tank is too high and the excess water in from the expansion is filling the tank past the overflow level and overflowing.
You can try adjusting your float valve to see if will help but this would have been set to the correct level when first commissioned.
I presume it has been functioning correctly for a while, therefore there is still a underlining problem.
You need to get this looked at by a pro
I presume it has been functioning correctly for a while, therefore there is still a underlining problem.
You need to get this looked at by a pro
assume the three port valve sticks between ports ie flow restriction
water takes the path of least resistance ie vent
water takes the path of least resistance ie vent
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