Santon Premier cylinder sudden decrease in water temp

[batty368b]

I would be so glad on any advice regarding my following problem!
We have a Santon premier water cylinder (model TP150B) which was installed 7 years ago.
Up until last Wednesday we have enjoyed a daily tank of piping hot water ! However, literally from one day to the next, the tank is now only producing tepid water even though the central heating is working perfectly.
I will be on my 3rd British gas engineer visit tomorrow! He changed the motorized valve yesterday to no effect. (Still tepid water and miserable children in almost cold baths!!) Even using the boost button, only produces a kitchen sink full of useable hot water.
Can anyone out there throw some light on the possible variuos causes of the above.
Many many thanks in anticipation
Glenda B xx

 

[gas4you]

What boiler etc do you have? I would suspect the pump possibly, or do your rads heat up properly, if so how about the cylinder stat on the Santon.

You should have an immersion back up on the Santon. Turn this on for now.

 

[chrishutt]

How is the cylinder heated? If it's from a boiler then you need to work logically through the control system. Is the cylinder stat operating properly? Is the motorised valve opening when it should? etc. It's usually pretty simple to determine the fault, unless you're a BG "engineer" of course.

 

[batty368b]

Wow! Thanks for your speedy response! We have a Vailant boiler which was checked by the engineer and is working fine as the radiators all heat up!
The point about the cylinder stat (Sorry is that short for thermostat?) has been mentioned by another reply so I will "suggest" that to the engineer tomorrow. Hopefully it will be 3rd time lucky and the problem will be sorted tomorrow!
Again thank you

 

[chrishutt]

I will "suggest" that to the engineer tomorrow.

Any engineer would have checked that to start with, so if he hasn't checked it yet he isn't an engineer, or even a technician, and shouldn't be meddling with anything with wires connected to it.

 

[JohnD]

put your hand on the pipes round the 3-way valve and see which are hot. If he only changed the motorised head, not the lower part with the water in it, in might be jammed or clogged.

Look for a stat strapped to the side of the cylinder (but don't touch it, if you have an engineer coming, he can do that). See if it has a small adjusting knob that can be turned with a screwdriver. maybe it is set too cool or is broken or out of adjustment. It should indicate numbers (degrees) and have a pointer set to a number about 60.

Bleed the highest rad in the house and see if water squirts out of it forcefully, and if it is black. is this rad higher or lower than the cylinder?

 

[batty368b]

Oh heck! I presumed that all British gas engineers are fully trained and compentent, particularly as I pay a hefty monthly premium for their services when needed!
Thankfully hubby can stand over the chap's shoulder tomorrow and monitor what he does/doesn't do! He's not a heating engineer but he does have so much more of a clue than I regarding basic fault diagnostic techniques! Thank you again for your reply and advicce. Glenda

 

[chrishutt]

put your hand on the pipes round the 3-way valve and see which are hot.

If it's an unvented cylinder it should have a 2 port valve on the flow pipe to it, even if there's also a 3 port valve. It's part of the fail safe system.

Anyone working on an unvented cylinder should have the "unvented ticket", an identity card to show that the person has undertaken a short course and assessment on unvented cylinders. Ask the "engineer" if you can see his "unvented ticket" (not the Corgi card).

If he doesn't have one or won't show it, ask him for the name of the BG manager who is authorising him to work on unvented cylinders when not competent to do so. He'll quickly disappear and you should get someone competent within a few days.

 

[batty368b]

Thank you chrishutt for that valuable advice. I had just returned from hugging the cylinder tank to see if there was a thermostat on the outside of it! (There doesn't appear to be!)
I've just spoken to hubby, typical he works away all week, hence I have to deal with these things from Monday to Friday lunchtime! He will tackle the chap tomorrow concerning his additional qualifications.
Hopefully others will read your message as well and ask for proof of additional training where unvented systems are concerned.
All the best, Glenda xx

 

[chrishutt]

I had just returned from hugging the cylinder tank to see if there was a thermostat on the outside of it! (There doesn't appear to be!)

There must be a stat and overheat cut-out. It's surface mounted but might be under the plastic covers on the side or on top. Look for the cable running to it.

 

[gas4you]

Follow flex as Chris says. Not all BG employees are as good as those who post on here Sorry nickso

 

[batty368b]

Thanks again chrishutt and gas4you you're very kind to be so helpful! I now have a poorly daughter who has had 3 tepid baths already topped up with water from the kettle. Thank goodness the washing machine heats it's own as I'm on my 5th load since midnight!!!

I am hoping and praying with all of the pointers you have given me, even the most junior engineer will be able to fix my problem today when they are presented to him!!

Again many thanks

 

[Agile]

I occasionally find these "faults" appear when the central heating has started to be used because the time clock or boiler stat is changed and the user fails to realise that the cylinder needs a time to heat up.

Of course the Santon will heat up quickly if it has a high enough flow temperature but sometimes the user sets the boiler to a lowish radiator temperature which is insufficient to fully heat the cylinder.

Muppets dont consider the operating parameters first!

Tony

 

[batty368b]

Hopefully this will be my final entry!
On contacting BG call centre, I asked if the previous engineers who had attended had their unvented system additional qualification. The telephanist didn't know.
However, instead of the young lad arriving today who had fitted the motorised valve yesterday, a chap with "26 yrs" experience turned up on the door step today!
He went through all of those basic checks which chrishutt mentioned and found that the motorised valve had been wired incorrectly yesterday.
He was here ages compared to the other engineers so fingers crossed, the call centre got fed up with my repeated calls and sent someone out who was experienced with an unvented system and will get me sorted.

 

[ChrisR]

Heavens to Betsy. Here's hoping!

But you still need to get the backup Immersion Heater issue resolved for the future.
You should have a box of some sort on the outside of the cylinder, with a thick wire coming out, going to, usually, a switch on the wall. They heat slowly by comparison, but are well worth having working.