Hot water on all the time..?

[MustangMark]

Hello,

I appear to be having a problem with my hot water.

I noticed today that the water is hotter than the temperature set on the sensor. I set it at 55 and the gauge on the cylinder reads 65.

After looking into this in a bit more detail it seems like the hot water is on all the time, even though the timer\control unit on the wall in the kitchen says both the water and heating is off.

So basically the boiler is running all the time regardless of the timer, and this appears to be warming the water up continuously.

Any ideas before i pick the phone up..?

Any tests I can do to understand what is actually at fault..?
Cheers
Mark

 

[weareleeds]

What kind of boiler system etc ie combi, back boiler, wall mounted do you have a y-plan s plan c plan m plan etc etc etc

 

[gas4you]

You havent really told us much? Do you have a 3 port valve or 2 x 2port valves? I suspect that either the 3 port valve is faulty allowing the hot water on all the time (microswitch stuck telling boiler and pump to fire) or the heating 2 port valve is doing the same! Check for 230v on the orange wire out of valve. Should be dead when hot water set to off.

 

[MustangMark]

Hi mate,
Thanks for the quick reply... much appreciated...

OK here goes...

In the garage is an Ideal Classic boiler with a pump situated above it

In the airing cupboard is a Telford Tornado cylinder which is a mains pressure and indirect. Attached to this is a temperature control unit and an immersion heater. A pipe in from the boiler, and a pipe out back to the boiler. These pipes are hot all the time, even though the timer is set for the water to be off through the day.

Around the cylinder are is other pipework that i think relates to the CH system. Also in all this pipework are a couple of electronic valves...

Does this paint a clearer picture..?

Please let me know if I need to be more specific !

Help!

Cheers
Mark

 

[gas4you]

The valve that is in the flow to the Telford cylinder is the suspect one. Check for 230V on orange wire as said before. If live whne controls turned off for hot water, replace head.

Does anyone on here know if this is allowed to be replaced by op as it is classed as a safety device for the un-vented cylinder, or has it got to be done by un-vented qualified op? Or is this a grey area?

 

[MustangMark]

OK, I think I can see the valve you are referring to.

Does all this unit have to be replaced, or can just the top plastic bit be replaced..?

Is it a DIY job..? (I am not an idiot when it comes to using spanners, did a 4 year engineering apprenticeship...)

How much are the parts..?

What would you expect a qualified plumber\engineer to charge..?

I really am impressed with the help so far...!!

Cheers
Mark (Selby, North Yorks)

 

[gas4you]

My last comment above was not meant to imply you are an idiot, just a question I am uncertain about on the regs side of things.

The changing of the valve head is very simple as long as you are comfortable with wiring

 

[MustangMark]

Dave,

I never thought you were referring to me as an idiot as I know these unvented systems are all tied up with regs. To be honest I struggle to find a suitably qualifed plumber in my area to come and service the damn thing..!!

I could do with checking for the live wire first, I'll get the father-in-law round with his meter....

Where do I get the part from..? Is it a B&Q job..? How much as a guide..?

Do I need to switch\isolate the system in any way..?

What has surprised me is that the temp gauge on the cylinder is not restricting the firing of the boiler... but what do I know about CH and HW systems..?!!!

Cheers
Mark

 

[gas4you]

The hw valve has 2 live supplies into it. One is controlling the synchron motor to open and shut the valve, the other is a permanent live to the microswitch that is operated as the valve opens and shuts. Either the valve hs stuck open, or the microswitch has jammed on therefore ignoring the requests of the cyl stat.

This hw valve is also classed as a safety feature so that in case the boiler does not switch off then valve shuts to stop the hw over heating and causing the un-vented cylinder to over pressurise!

I suppose in theory if the safety device has failed then you should not have the system on

I do not know if the 'shed' carries spares, usually you would go to parts centre or another local parts supplier, or buy from one of the internet supply shops

 

[MustangMark]

Just managed to "dis-mount" the valve in question. Push a button and turn.

It is a Honeywell Double Insulated Actuator - VC4613

Just so I can understand the problem better... What is it that this unit actually does..?

Cheers
Mark

 

[MustangMark]

Dave

Think between us we've sussed it..!!

Whilst the top bit was off I pushed on the valve "plunger" and hey presto, it slid out into what i suspect is the closed position.

So your expert diagnosis was correct. The valve was stuck open.

I have remounted the top bit and the boiler has now switched off..!!

Perfect.

Many thanks to those who have helped me... Can't wait to tell the blokes at work about this site.!!

Cheers
Mark

PS - Lager time now..!