Plumbers Help - Hot Water Cylinder - No pressure relief valve??

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Bung

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#2501240 9-Jun-2020 10:30

Im sorry but you are just guessing. The relief valve is on the outlet, why would you need to empty the cylinder? There may be some water in the pipes above the valve but shutting off water going into the tank and opening a hot tap below the valve height will get rid of most of it.

nickb800

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#2501241 9-Jun-2020 10:35

Yes, only need to turn off water inlet and power, don't need to drain cylinder

samgdan

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#2501243 9-Jun-2020 10:40

Bung: Im sorry but you are just guessing. The relief valve is on the outlet, why would you need to empty the cylinder? There may be some water in the pipes above the valve but shutting off water going into the tank and opening a hot tap below the valve height will get rid of most of it.

with people help I managed to locate the pressure relief valve, but this has no lever to relief any pressure.

i believe the tank needs to be empty as if there is pressure that I want out I dont want water out as well (very hot water) I know most likely my logic does not make sense but that is what it comes to my mind.

i will try shutting off the water going into the tank and then open a hot water tap later tonight.

thanks for the help.

sounds good to have the sound working

samgdan

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#2501245 9-Jun-2020 10:41

nickb800:

Yes, only need to turn off water inlet and power, don't need to drain cylinder

ok I will give it a go this weekend with more time.

however if the pressure relief valve is "working well" the water dripping would that indicate another issue?

sounds good to have the sound working

nickb800

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#2501250 9-Jun-2020 10:50

samgdan:
nickb800:

Yes, only need to turn off water inlet and power, don't need to drain cylinder

ok I will give it a go this weekend with more time.

however if the pressure relief valve is "working well" the water dripping would that indicate another issue?

The pressure reducing valve could be supplying too much pressure. This is the black/brass flying saucer like thing with a yellow tag on the intake. You might be able to adjust the pressure down on this, or it could be faulty.

I think the pressure relief valve attached to the tundish is most likely the problem though

mclean

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#2501252 9-Jun-2020 10:51

It looks like an APEX pressure limiting valve.

Some dripping here is normal as the water heats up. Otherwise it could be a dirt under the seat of the valve, or the main pressure reducing valve on the incoming pipe might be set a little high.

You can get the APEX catalogue from https://www.wattsnz.co.nz - there are good fault-finding guides in there. Your system is low pressure valve-vented.

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BlueOwl

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#2501259 9-Jun-2020 10:54

samgdan:

nickb800:

Yes, only need to turn off water inlet and power, don't need to drain cylinder

ok I will give it a go this weekend with more time.

however if the pressure relief valve is "working well" the water dripping would that indicate another issue?

Yes, you've got a leak - probably an old joint has opened up or the pressure reducing valve is leaking. I've seen what happens when someone takes a spanner to some old joints at the bottom of a hot water cylinder - the cylinder immediately emptied itself onto the floor.

With all due respect, I think you should call a plumber at this stage.

Bung

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#2501262 9-Jun-2020 11:01

If you go to manufacturer's website like Nefa you should find a troubleshooting procedure that identifies whether it is the reducing valve set too high or the relief valve leaking. The principle is the tank fills withcold water at a certain pressure and this water expands as it heats up. To keep the pressure constant the relief valve should bleed off water until the tank reaches a steady temperature then stop. If it keeps dribbling either it isn't sealing or the inlet valve is sdt higher than the relief.

samgdan

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#2501722 9-Jun-2020 20:02

thanks to everyone for the help.

I will be contacting a plumber in the comings days.

I was about to give it a go but if for some reason something goes wrong over the weekend a call out will be very costly.

What would be the average price to replace the pressure relief valve including labor? i found some valves for 100 +gst new ones how long this work could take? 2 hours including testing?

Thanks,

sounds good to have the sound working

nickb800

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#2501793 10-Jun-2020 06:23

Valve could possibly be more. I would've thought one hour would do (without being a plumber myself). I'd budget $250-500, with a bit of an allowance for other things to go wrong.

samgdan

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#2502413 10-Jun-2020 17:19

nickb800:

Valve could possibly be more. I would've thought one hour would do (without being a plumber myself). I'd budget $250-500, with a bit of an allowance for other things to go wrong.

thank you for your help and everyone helps.

Plumber was at home today.

Pressure relief valve will be replaced along with the valve that has black plastic around(sorry I dont know the name)

estimate is about $400 including parts and labor.

hopefully replacing both parts will resolve the issue.

sounds good to have the sound working

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