Scudo triple shower valve - no water on one output

[trevt]

Long story short - replaced an existing triple shower valve with a scudo from local merchants as couldn't get a replacement cartridge for old one. What they had in stock rather than any other reason for choosing.

Once i had removed tiles etc it was straightforward swap with plumbing in place and roughly matching. Hot & cold inlets and two outputs, valve has three controls. Top for overhead outlet, bottom for siderail shower and middle to set temperature.

Plumbed and turned on - overhead works perfectly. Siderail - no water.

Tried with overhead running and not.

Both outputs worked on previous shower and i have not touched any other connection other than compression joint at shower valve.

I haven't turned cold water pressure fully on, so suppose it could be pressure but would assume neither would work if pressure too low. BTW another triple valve shower in another bathroom works fine so another reason not pressure related?


Any ideas?

 

[CBW]

Have you turned an isolation valve off and forgot to turn back on? Is it all connected as it should be?

 

[trevt]

Thanks. I have done stupider things, but not this time.

No isolation valves etc, just undid four joints and re-made on new valve after turning off mains. The shower works perfectly on one output but nothing on the other - so water is flowing into and through the valve.

 

[CBW]

I’m guessing if everything is as it should be then it could be a fault on the shower.

 

[trevt]

It gets better......

The reason i changed the valve was because the shower went cold after a few minutes and wouldn't run warm again - suspect cartridge. I can't get a replacement so took the option of valve replacement.

The new one ran warm last night, albeit it for a few minutes before i switched off. Ran it for longer this morning, mainly to check no weeping joints etc and it did same thing. Hot water for a brief minute, then cold.

System is sealed with boiler filling a tank much bigger than we need - we never run out of hot water. Two other showers (one exactly same as original valve) run perfectly with no issues. Can use one of them after using the dodgy one and runs fine - definitely not an issue with enough hot water.

Mains pressure is very good and can run two showers simultaneously/multiple taps etc with no noticeable drop in pressure.

Plumbing was installed about 5 years ago completely new.

Confused