On Tue, 13 Apr 2004 00:05:57 +0100, "Set Square"
wrote:

In an earlier contribution to this discussion,
Matthew Humphreys wrote:

On Mon, 12 Apr 2004 11:20:09 +0100, "Set Square"
wrote:

In an earlier contribution to this discussion,
Matthew Humphreys wrote:


Which of the connections to the valve should be live for just the hw
to be heated?


Essentially none - but the wire which is connected to Pin 8 in the
junction box will be live because Pin 8 is powered from elsewhere.
Some of the others may glow dimly on your screwdriver because
they're connected via the motor windings etc.

The valve is least active in the Hot Water only position. It sits at
its "home" (spring return) position, where it directs water only to
the heating coil in the hot water cylinder. In this position, the
actuator plays no part in switching the boiler and pump - they are
switched by the cylinder stat. --
Cheers,
Set Square
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Please reply to newsgroup. Reply address is Black Hole!


OK, perhaps we're getting somewhere!

I've had all the wiring double checked by a friend - we are confident
it is OK.

When I ask the system for hw on pins 6,7 amd 8 are live.
When the water is hot, 7 and 8 are live (7 is HW off, 8 is feed to the
boiler as you explained above.

This now seems to be logical!

One thought I had was that as the system is expecting a Danfoss
Randall 3 way valve, which has the CH/HW - A/B ports the other way
round (doesn't it?) and I have a Honeywell 3 port valve, is the
controller trying to ask the port to do the "wrong thing"?

If this is utter tripe, please tell me, I'm a mechanical engineer not
an electrical /heating engineer!

Is there any way to manual operate the valve to the "rest"/ HW only
position to see of the valve is playing ball.

What else can I do to check the valve is OK?

Any other ideas anyone?

Thanks for all the help over the last few days,



Matthew

If you're working to the Danfos schematic, Pin 8 shouldn't be live when the
water is hot - unless the central heating is also on.

My mistake - pin 9 is dead when the tank is hot. It's been a long
day.....



When you turn all the power off to the heating system (at the main switch -
not the programmer) you should hear the valve return to its home position -
unless it is already there, in which case you won't.

If you want to check it's the right way round, disconnect the valve
completely from the junction box but leave everything else connected. Run
the system in the HW only mode. Hot water from the boiler should circulate
through the heating coil in the cylinder but not through the radiators. If
the radiators get hot but the heating coil doesn't, the valve is the wrong
way round!


Will try that tomorrow.

If you are using a Honeywell valve with a Danfos junction box, the valve
wiring should be (as far as I can work out!):
Blue - Pin 2
Green/Yellow - Pin 3
White - Pin 5
Grey - Pin 7
Orange - Pin 8


thats what I've got too.

--
Cheers,
Set Square
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Please reply to newsgroup. Reply address is Black Hole!


Cheers,

Matthew