Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Taxi_Driver]

Does this sound like a knackered controller?

I have a 7day timer that controls the hot water and central heating independantly.
Its a Horstman channel Plus and also one of those 3 way valve jobbies

If the hot water comes on....all is fine...I get hot water.

If the heating and hot water comes on ...again is fine...I get hot water and central heating.

If the heating comes on its own....all is not fine....i get zilch.....no heating   But the led is light on the controller to say the heating is on.
When its like this.....ive checked the pump....its not running.....nor does the boiler fire up.

Should add pump runs fine if hot water is on or hot water and central heating.

My temp fix.....is ive set the hot water to 24hours on.....central heating switches on and off just fine like this.

Its been doing it for the last 3 days.

The only thing i can think it is ....the controller is fubared somehow  :-/

[Kevin Wood]

I doubt it's the controller as this just supplies power to the valve to open it up to the central heating circuit and that is clearly working.

The problem will be associated with a little microswitch in the valve. This is supposed to fire up the boiler and pump when the valve moves into the "central heating on" position. Since these are already powered when the hot water is on, it works in that configuration.

You might find that the valve is sticking so it doesn't fully open and thus doesn't get far enough round to activate the microswitch, or that the microswitch itself is knackered or needs its position adjusting.

You should be able to take the cover off the valve motor and observe what's going on. Beware that there will be mains voltages inside it if the supply to the central heating is on at the spur box which feeds it!

A squirt of WD40 on the gears in there may help, or there may be a visible clue as to why the switch is not operating.

Kevin

[CaptainZok]

You could try a pm to Boiler Man TD.

[STMO123]

Had this trouble with mine TD. A gentle tap on the three way valve sorted it for a while, but had to replace it eventually.

[Taxi_Driver]

I doubt it's the controller as this just supplies power to the valve to open it up to the central heating circuit and that is clearly working.

The problem will be associated with a little microswitch in the valve. This is supposed to fire up the boiler and pump when the valve moves into the "central heating on" position. Since these are already powered when the hot water is on, it works in that configuration.

You might find that the valve is sticking so it doesn't fully open and thus doesn't get far enough round to activate the microswitch, or that the microswitch itself is knackered or needs its position adjusting.

You should be able to take the cover off the valve motor and observe what's going on. Beware that there will be mains voltages inside it if the supply to the central heating is on at the spur box which feeds it!

A squirt of WD40 on the gears in there may help, or there may be a visible clue as to why the switch is not operating.

Kevin

Oh buggar  

Thought it would be easy option of changing the controller....

I have noticed that the 3 way valve is in the in central heating position when just heating selected on the controller....but from your post theres more too it than that  :-/

Reason i thought it was the controller...was when both hot water on and central heaing on the 3 way valve stays in the middle to start with then when hot water upto temp it moves over heating only and still works ok.....but if i turn off the hot water the heating goes off too  :-/

[Taxi_Driver]

You could try a pm to Boiler Man TD.

Good idea....

[Admin]

Or you could wait for Mark to comment...

Yes he happens to be a an expert on Central heating system too (one day I'll find something he is not entirely knowledgeable on!  )

[Marks DTM Calib]

Motorised valve.....as said, sounds like a goosed micro switch....

What you have to remember is that on most installs of this type, the programmer simply feeds a live feed via the room or tank stat to the valve, the valve then moves to the required position and presses the micro switch......its the micro switch that fires the boiler and turns the pump on.....

If the main valve body is still ok and dependent on the make of valve....you can simply swap the motor and control body over to save draining the system.....

[Boiler Man]

Hi Guys

Without being able to carry out a couple of tests myself, I suspect it is as 2 off the lads have previosly suggested, that is a faulty 3 way valve. Is it a 3 way valve or 2 zone valves?

It sounds like the micro switch is faulty, it isnt always the case of the switch not making, but that it isnt putting out the required supply to start the boiler and pump.

Do you have the details of the valve motor?

most modern valves have motors that are easy replaced without a drain down.

[Taxi_Driver]

Hi Guys

Without being able to carry out a couple of tests myself, I suspect it is as 2 off the lads have previosly suggested, that is a faulty 3 way valve. Is it a 3 way valve or 2 zone valves?

It sounds like the micro switch is faulty, it isnt always the case of the switch not making, but that it isnt putting out the required supply to start the boiler and pump.

Do you have the details of the valve motor?

most modern valves have motors that are easy replaced without a drain down.

Its a 3 way valve.....says on it 'acl lifestyle mid position valve' and prolly been fitted for about 12 years, so not exactly modern  

[Auto Addict]

Hi Guys

Without being able to carry out a couple of tests myself, I suspect it is as 2 off the lads have previosly suggested, that is a faulty 3 way valve. Is it a 3 way valve or 2 zone valves?

It sounds like the micro switch is faulty, it isnt always the case of the switch not making, but that it isnt putting out the required supply to start the boiler and pump.

Do you have the details of the valve motor?

most modern valves have motors that are easy replaced without a drain down.

Its a 3 way valve.....says on it 'acl lifestyle mid position valve' and prolly been fitted for about 12 years, so not exactly modern  

It's done well if it's lasted 12 years......

[Taxi_Driver]

Had this trouble with mine TD. A gentle tap on the three way valve sorted it for a while, but had to replace it eventually.

Ive just tried that....to see if it sorted it....and stopping short at smashing it with a baseball bat it made no difference.  

Ive just had a little play with the controller again.....and boiler turned off.....coz controller is right next to boiler and its difficult to hear with boiler on.

If i press the hot water button you can hear a definate click from the controller...probably a relay switching....if i press the hot water button again....again another click.

If i press the heating button......nothing but silence.....on light comes on tho, same as it does for the hot water.

Is it still likely to be the 3way valve??

I am appreciating the replies and learning very fast how the system works  

I'll soon be a heating engineer  

[STMO123]

Switch it to heating only, then tap (welly) the valve. It will only run the little motor if its not already in the position it needs to be in?

F*ck me, does that make sense?

[Taxi_Driver]

Switch it to heating only, then tap (welly) the valve. It will only run the little motor if its not already in the position it needs to be in?

F*ck me, does that make sense?

I did try it that way.....heating only on.....pointer on the valve pointed at heating only and i whacked the valve from all angles with a big heavish rubber torch (1st thing that came to hand   )

Tho ang on......i think your saying your valve didnt change position until lightly tapped.....mine does change position correctly.....but as other posts have pointed out theres a microswitch in the valve that might not be working  :-/

[MikeDundee]

(one day I'll find something he is not entirely knowledgeable on!  )

How about a mitsubishi Triton