Kingspan Tribune XE cylinder, air gap needs frequent replenishment

[stormyuk]

Hi there,

Did you ever get to the bottom of this Postik?

I have a Tribune XE which exhibits the exact same behaviour as yours down to the pressure at the tap when the tundish is about to start dripping.

Interestingly I've had the cylinder replaced twice under warranty (1st was sticky diaphragm which made the tank excessively noisy on heating cycles and the 2nd only last year due to a faulty installed Immersion heater). They have all suffered the excessive recharging required so I think it's definitely something external to the cylinder.

I have to represussure mine every 4 months almost to the calender day. I too have 2 bar showers and multiple mixer taps in the house. I do wonder if there is some back pressure from the cold feed as mine was never installed with a balanced cold feed (it's just blanked off). Lazy new build installers I guess here. So do wonder if due to all the mixer taps this is the culprit.

After I represussure it works fine for a other 4 months. Wondering if you solved yours or just lived with it.

Cheers,

 

[Johntheo5]

I,ve since been told by OSO technical that their cylinders don't have a baffle, these bubbles are recharged starting with a practically empty cylinder and all hot taps closed, don't know how often they require recharging but I reckon that if you were to recharge your tribune similarly that (theoretically anyhow) you may get up to 5 times longer between recharges, also, the final pressure after a full reheat will be lower at 3.2bar vs almost 4.0bar (3.97) assuming a full reheat to 60C.

 

[Postik]

Hi there,

Did you ever get to the bottom of this Postik?

I have a Tribune XE which exhibits the exact same behaviour as yours down to the pressure at the tap when the tundish is about to start dripping.

Interestingly I've had the cylinder replaced twice under warranty (1st was sticky diaphragm which made the tank excessively noisy on heating cycles and the 2nd only last year due to a faulty installed Immersion heater). They have all suffered the excessive recharging required so I think it's definitely something external to the cylinder.

I have to represussure mine every 4 months almost to the calender day. I too have 2 bar showers and multiple mixer taps in the house. I do wonder if there is some back pressure from the cold feed as mine was never installed with a balanced cold feed (it's just blanked off). Lazy new build installers I guess here. So do wonder if due to all the mixer taps this is the culprit.

After I represussure it works fine for a other 4 months. Wondering if you solved yours or just lived with it.

Cheers,

Hi Stormyuk,

Unfortunately I haven't gotten to the bottom of it. I also have a piece of pipework that is blanked off and I remember the plumber saying it wasn't installed properly "due to laziness", but that it "didn't matter," so perhaps there is something in this.

I got fed up of the tundish catching me out, as when it starts dripping it splashes everywhere. In the end I added a recurring event to my calendar every 3 months to remind me to proactively recharge it. When I open the valve I stick a pound coin in the gap so I don't have to stand there for 20 minutes.

I've also found that after recharging I have to clear out the kitchen tap aerator (the tap I leave open whilst recharging) which will have collected little bits of white plastic. From research I think these small granuals are from the plastic spreader/baffle disintegrating inside the tank. The collection of the little plastic pieces decreases over the course of a day or two and then stops completely until the next time I re-charge the air gap. It only occurs in the tap that's left open and they haven't collected in any other outlets. I understand this isn't a good thing but I don't know whether a small amount is normal during the process of recharging.

The boiler is getting on for 8 years old now so I am gearing myself up for needing a replacement in a couple of years. At this stage I am not sure whether to also replace the hot water tank, or whether to bin it off and get a combi boiler instead. I am nervous about the latter as it's a 4 bed house with 2 showers and a downstairs loo, although my plumber thinks a combi should be able to cope.

If you figure anything out in the meantime please do let me know!

Thanks,

 

[stormyuk]

Hey, thanks for the response.

I'll check the kitchen tap aerator when I recharge mine in the next couple of days.

Luckily my kitchen tap tends to let me know when mine needs doing before it becomes a torrent in the Tundish. So thankfully water not usually everywhere.

I think there is definitely something to do with back pressure through mixer taps / showers which leads to early recharge because they should ideally have a balanced cold feed and it seems lazy builders CBA to plumb all that.

Mine is due a service this week and I'll ask the plumber as he used to work for Kingspan and installed a lot of these. I am sure he mentioned sometimes they fit a non return valve on the feed from the hot tank in some situations to stop this.

I'll let you know if I learn anymore.

Cheers,

stormy