Glow worm Ultimate 60FF

[philip134]

Glow worm 60ff


4073A mid position valve seemed to be sticking. Delivering CH when only HW was called. Loosened spindle, replaced activator head, lots of clicking noises from head.


Now boiler doesn't fire. No lights on any of Neons 1 to 4. L to N inside box has 240v. N to SL has 0v. Connected L to SL - boiler fires, all 4 neons lit, pump runs.


Does this suggest that 4073A head is at fault? or pcb is at fault? Can I check some voltages on wires from activator head to help in sorting the problem?


Philip

 

[PlumbBobBob]

sounds like the activator head is at fault to me

 

[diamondgas]

If it worked ok before you swapped the head I'd be double checking your work Philip .... :welcome: to the forum ... If you don't have 240 on the SL then the fault is external from the boiler! You did swap the head yeh?

 

[philip134]

Yes swapped the old head - one that seemed to be sticking - for a new head bought sometime back.

Perhaps the 'new' one has duff micro switches inside? But how does that make the SL 0v?

 

[diamondgas]

Yes swapped the old head - one that seemed to be sticking - for a new head bought sometime back.

Perhaps the 'new' one has duff micro switches inside? But how does that make the SL 0v?

On hot water only the valve doesn't do anything Philip. Boiler should still light up and pump run suplied from the cyl stat 🙂

 

[southcoastboile]

Dont leave the link between sl and l whatever you do.

If you have no voltage to sl it is definitly an external controlls fault and nothing to do with boiler

 

[philip134]

Thought it would be helpful to add some information I found elsewhere

Yes making a link between L and SL in the boiler tells you if it is a boiler or a control problem. If the boiler fires the fault is with the controls. Here are some notes on checking the controls.

Mechanical: valve sticking or valve passing.

The symptoms of this are pipes getting hot when they should not. Typically you get CH when only HW has been called. This means that either the valve is not moving fully over (sticking) or the valve is leaking when fully over.

The way to check this is to remove the actuator (box on top).

I had an old valve that had been fitted with a conversion kit (part no 40003918-007); This means the activator can be removed, and after drain down the valve guts can be removed - brass plate with spindle and rubber ball attached. The spindle should rotate with just finger and thumb pressure - anything more and the activator motor will find it hard to move the spindle. If you grease the spindle, rotate it a lot to free it you can try mounting it again. Put activator in manual position and screw it down - release from manual position and with no power it should spring back all the way - if it doesn't your efforts to free the spindle are in vain. Buy a new conversion kit (about £12) and refit everything. This solved my problem.

If you have a new valve without a conversion kit then I think you will need to buy a whole new valve body, drain down and fit it - lots of compression joints to break and remake. It is possible to get a repair kit consisting of the ball and 'O' rings (part no 272752A), but this does not solve the sticking spindle problem. So surprisingly dealing with an old valve is easer if your spindle is stuck.

If the valve is not sticking or passing, there may be a problem in the actuator

Checking Actuator

.Before assuming the valve is faulty, check that the wiring is correct and all terminals done up.

Most of the tests can be carried out without a meter, but voltages have been given as well.

Check valve for sticking/passing before doing electrical tests (above).

The actuator must be attached to the valve.
Carry out tests in sequence given.

CH Only Test (Port A open)

Turn Power OFF at main connection for the system (turning CH and HW OFF at programmer is not sufficient) This resets the valve to rest position
Disconnect white valve wire and grey wire from terminals in junction box (remember which terminals these are, you will need to reconnect them!!)
Connect white and grey wires to a permanent Live in the box
Turn Power ON
Valve should move over so port A is open and boiler light (check by feeling that only the pipe from port A gets hot)

If the valve does not move, Switch S1 is not moving over.
If the valve moves but the boiler does not light, switch S2 is not moving over. (check 240V on orange)

HW Only Test (Port B open)

Power OFF (valve returns to rest position)
Turn HW stat to lowest
Disconnect grey and white from the permanent Live and temporarily make safe (e.g connect to spare terminals in the wiring centre)
Disconnect cylinder stat Common wire from its terminal in the box (remember which one!!) and connect to a permanent live
Power ON
Turn cylinder stat to max.
Boiler should light. (check by feeling that only the pipe from port B gets hot)
If it does not light, the cylinder thermostat is suspect (check for 240V at Common and Call terminals of cylinder stat and at terminal 8 ).

CH and HW Test (Ports A and B open)

Power OFF
Turn cylinder stat to lowest
Disconnect cylinder stat wire from permanent live and reconnect to original terminal
Disconnect white wire from temporary location and connect to a permanent Live
Power ON
Valve should move to mid position
Turn Cylinder stat to max
Boiler should light (check that pipes from ports A and B both get hot).

If boiler does not light cylinder stat is faulty
Power OFF
Reconnect white and grey to original terminals
Turn HW OFF and CH ON
Set CH stat high
Turn Power ON
Valve should move to Port A open, boiler light and Port A get hot.
Turn CH OFF, so boiler goes out.
Boiler should go out but valve stay in CH only position
If boiler does not go out, check voltage on orange wire.
If orange has 240v, the actuator is faulty
If orange has 50-150v, there is a problem with the boiler

If these tests are passed, the problem is elsewhere.

Testing other components

Cylinder thermostat:disconnect wires from CALL (1) and SAT (2) terminals in box (remember which ones!!) when checking, this prevents false readings due to back feed.

There should be 240V on Call (1) when stat is turned up and 240v on Sat (2) when stat is turned down

Room thermostat: disconnect wire from Switched Live when checking to prevent false readings due to back feed.

There should be 240v on Sw L (3) when stat is turned up and 0V when it is turned down.

Note: you may find that terminals 1 (live) and 3 (Sw Live) of the thermostat have been swapped over. This is not too important for modern digital thermostats but should be corrected if you have the older mechanical thermostat.

Programmer: Check voltages at CH ON, HW ON and HW OFF terminals when programmer set to appropriate positions. Also check the voltages when the timer is used to switch on/off.



​

 

[diamondgas]

You fixed your boiler then?

 

[philip134]

You fixed your boiler then?

Yes, with the new conversion plate the spindle moved easily and the valve was back to working as it should. Also had the added advantage of getting a new rubber ball so the seal on both ports was improved.

The old conversion plate WD40'ed would move with a small wrench but only all all the might in your finger and thumb!

 

[diamondgas]

Yes, with the new conversion plate the spindle moved easily and the valve was back to working as it should. Also had the added advantage of getting a new rubber ball so the seal on both ports was improved.

The old conversion plate WD40'ed would move with a small wrench but only all all the might in your finger and thumb!

Been a long time since I've replaced the guts of a diverter philip134 ... Congrats on persevering 🙂 Did the parts cost much? Where did you get them from?

 

[philip134]

Been a long time since I've replaced the guts of a diverter philip134 ... Congrats on persevering 🙂 Did the parts cost much? Where did you get them from?

£12.50 delivered in 2 days from the dreaded Ebay!!

 

[diamondgas]

£12.50 delivered in 2 days from the dreaded Ebay!!

lol ... Saved you a bit though 🙂 I didn't know you could still get the guts on these... Repair side has become more of a parts swaping exercise than fix these days!

 

[GrahamM]

£12.50 delivered in 2 days from the dreaded Ebay!!

Not bad at all.
Thanks for the update.