Santon Premier Plus running out of hot water

[fsharrock]

I had a Santon Premier Plus installed 18 months ago to replace my ageing Gledhill Accolade. Everything was fine and dandy with lots of lovely high pressure hot water until I had a new bathroom fitted. Since then the hot water seems to run out much faster. There is another occasional symptom: sometimes, even on the first shower of the day, I have to put the mixer tap on a much hotter setting than normal to get my desired water temperature. I presume this is caused by the temperature or pressure of the hot water being lower than normal.

I'm a bit mystified by all this, and unsure whether it could be caused by the bathroom works, or simply a coincidence. It could be that the new shower head simply uses more water than the old one, although it doesn't seem to. And that wouldn't explain the occasional mixer tap effect.

I had a similar problem with the Gledhill earlier in its life and was advised to recreate the air buffer by doing the following, which worked. Could this help on the Santon too?

1 Turn off the power to the elements
2 Turn off the water at the stopcock
3 Open the lowest hot tap and when the water stops leave it open
4 Turn the pressure release valve on the side of the cylinder - about 1/2 way up on the left - and water will flow out through the drain
5 Keep valve open until the alarming gurgling noises inside the cylinder calm down and water stops flowing - can take a few minutes
6 Close the hot tap
7 Turn on the water at the stopcock and wait for the gurgling to stop
8 Open hot tap slowly - the pressure is surprising - until air out of pipes
9 Turn the power to the elements back on

 

[baxpoti]

Santon premier plus does not have an integral air bubble.

 

[steve32]

as baxpoti said the santon premier plus does not have an internal expansion bubble it has an external expansion unit
all unvented units need checking every year by an unvented registered engineer (G3) they will check the expansion unit
the symptoms with your installation could be caused by many things the main things i would be looking at are

what temp is the hot water set at i set it at 60c
is the heat source (boiler or immersion heater) on long enough to reach temp
is the saton store large enough for your shower and usage (is the flow of your new shower higher than previous shower)
as i don't know the make of shower has it been set up correctly for temp adjustment on installation if required.
has the shower been installed on balanced supply's cold should be connected to pressure balancing valve on santon

hope the above helps

Steve