Sydney smart II,a poor Northern toilet?

[Grinch]

Last summer (2021) I installed a Caroma sydney smart II in a cottage washroom that gets drained every winter, and is left unheated.
It's in Eastern Ontario and the winter temps drop to -25C all the time.
I added RV antifreeze to the toilet in October as was done with the old toilet, shutting the supply valve off.
Today I filled the tank and flushed the antifreeze only to find the fill valve is not sealing and the tank overfill goes down the tube.
It had worked fine all last summer.
I removed and disassembled the ballcock/valve tower and didn't find anything out of the ordinary.
I reduced the fill level cutoff and reinstalled, no change.
Is this valve ballcock assembly just a "hothouse orchid" and am I going to have remove it every fall to store it in a heated room over winter?
The Caroma part number for the valve (top) is B3300-MA, the toilet P/N is 302100W

 

[Grinch]

While searching the web for information on Caroma warranties I found a list of conditions that void the warranty.
One condition listed was "extreme temperatures"....
I'm off to the hardware store today to see what can be done.

 

[Sponsor]

 

[Tuttles Revenge]

You're able to leave the water on in the cottage and only shut off the valve to the toilet? You might consider using air to blow out the water through the fill valve if just the residual water in the filler is an issue. Could likely install a schrader/bike valve right at the toilet supply tube that allows you to turn off the valve and blow air just through the fill valve.

 

[Grinch]

The "cottage" is my principal residence, this bathroom is an unheated powder room that only sees use April to October, so the sink faucets & toilet supply are shut off as described.
What threw me was the old school ballcock/valve assembly went merrily through at least 20 years of casual winterizing with no issues. Once I thunk on it I realized as you have, the standing water damages the valve so I went and bought a Brass Craft fill valve.
(made in Not China) BCTO16 EF.
The top of the valve body 'pops off' so I can leave it open over the winter after blowing the water out. I was also considering unscrewing the supply line so gravity will drain the valve. Maybe I'll keep the rubber diaphragm in the house just in case.

 

[Grinch]

I remembered before installing the new valve that I had installed a household air induction clear iron filter last year and may have got some of the media in the water pipes so I flushed the pipe supplying the toilet in question really well....

PS; And I thought I'd say that other than the valve issue the Caroma brand is a winner....I first installed one in my main bathroom the year before and it's a champ....hasn't plugged up or malfunctioned once!

 

[Grinch]

This toilet developed a slow leak at the union nut supply tube/fill valve connection under the tank.
So as the fill valve was brand new and the supply tube was old I replaced the supply tube, no luck....the leak is at the fill valve apparently.I didn't over tighten the union nut.
I'm wondering if any quality plumbing fixtures are available, I thought Brass Craft was a good choice....

 

[Reach4]

It could be that the 7/8 connection was not tightened enough. Those are often in awkward positions. I would consider unscrewing the flex supply line at the toilet tank. Feel the bottom of the fill valve tube for roughness. Lube the threads both sides plus the gasket inside the supply with silicone grease. A Q-tip is useful for that.

Tighten the connection back, being careful to not cross-thread. You may need to use a hand holding the base of the fill valve tube inside the tank as you tighten the nut below. A helper would be handy, but otherwise do the best you can.

The lube on the threads and gasket will help get enough tightness without a lot of extra torque by your left hand.

 

[Grinch]

It could be that the 7/8 connection was not tightened enough. Those are often in awkward positions. I would consider unscrewing the flex supply line at the toilet tank. Feel the bottom of the fill valve tube for roughness. Lube the threads both sides plus the gasket inside the supply with silicone grease. A Q-tip is useful for that.

Tighten the connection back, being careful to not cross-thread. You may need to use a hand holding the base of the fill valve tube inside the tank as you tighten the nut below. A helper would be handy, but otherwise do the best you can.

The lube on the threads and gasket will help get enough tightness without a lot of extra torque by your left hand.

I had re & re the flush valve's 7/8" connection 3x, that connection was good / water tight.

I went as far as using pipe dope on the union nut thread's supply line but no solution....

The drip would only start when I opened the supply valve & the tank was empty but stop when the valve was closed even though the tank was full. I tried very tight & very loose settings on the union nut with no solution.

I went to Crappy Tire and bought a FluidMaster 400A flush valve and the leak stopped with the new valve installed.

Thankfully I kept the receipt for the Brass Master valve, so aside from my time and gas it will have been a wash.

The BM valve has a 10 yr warranty, the FM valve has a 5 yr warranty....

 

[Reach4]

Glad it's working. Too bad the first two tries did not fix it.

 

[Grinch]

Yeah, a shame. It would've been a no-brainer type of repair if the company that made the Brass Craft valve had a more robust QC procedure.....
I took the BC valve back to the Rona store I bought it from, they told me "too bad so sad" and pointed to the 1-800 number on the box the valve came in.

 

[Reach4]

Did you inspect the bottom of the Brasscraft valve and found it to be irregular? It could be that on your third try you used more grease and/or elbow grease.

 

[Grinch]

Did you inspect the bottom of the Brasscraft valve and found it to be irregular? It could be that on your third try you used more grease and/or elbow grease.

If you are talking about the 7/8 connection that wasn't the problem.

The leak was at the coupling nut/threaded shank, that area wasn't irregular.