Hi,
I've just tried to turn on the central heating after it being off all
summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working OK. Any
ideas/usual culprits? It was serving the hot water OK. It's a horstmann
controller and it's not a combi boiler system if that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

In an earlier contribution to this discussion,
Jon Telfer wrote:

Hi,
I've just tried to turn on the central heating after it being off
all summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working
OK. Any ideas/usual culprits? It was serving the hot water OK.
It's a horstmann controller and it's not a combi boiler system if
that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

We need a few more details about your system - gravity hot water and pumped
CH, or fully pumped? If fully pumped, how many - and what type - of
motorised valve do you have? [Likely either one 3-port valve (Y-Plan) or two
2-port valves (S-Plan) - see
http://content.honeywell.com/uk/homes/systems.htm]

Seemingly, something which hasn't been used for a while has developed a
fault in the meantime. If it's a gravity hot water system, I would check the
pump. Otherwise, look at the valve(s).
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

Set Square wrote:

In an earlier contribution to this discussion,
Jon Telfer wrote:

Hi,
I've just tried to turn on the central heating after it being off
all summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working
OK. Any ideas/usual culprits? It was serving the hot water OK.
It's a horstmann controller and it's not a combi boiler system if
that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

We need a few more details about your system - gravity hot water and
pumped CH, or fully pumped? If fully pumped, how many - and what type - of
motorised valve do you have? [Likely either one 3-port valve (Y-Plan) or
two 2-port valves (S-Plan) - see
http://content.honeywell.com/uk/homes/systems.htm]

Seemingly, something which hasn't been used for a while has developed a
fault in the meantime. If it's a gravity hot water system, I would check
the pump. Otherwise, look at the valve(s).

Going from the last bit first - I have a single three port valve and a
single pump (Y plan I reckon).

On Mon, 03 Oct 2005 19:32:46 +0100, Jon Telfer wrote:

Set Square wrote:

In an earlier contribution to this discussion,
Jon Telfer wrote:

Hi,
I've just tried to turn on the central heating after it being off
all summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working
OK. Any ideas/usual culprits? It was serving the hot water OK.
It's a horstmann controller and it's not a combi boiler system if
that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

We need a few more details about your system - gravity hot water and
pumped CH, or fully pumped? If fully pumped, how many - and what type - of
motorised valve do you have? [Likely either one 3-port valve (Y-Plan) or
two 2-port valves (S-Plan) - see
http://content.honeywell.com/uk/homes/systems.htm]

Seemingly, something which hasn't been used for a while has developed a
fault in the meantime. If it's a gravity hot water system, I would check
the pump. Otherwise, look at the valve(s).

Going from the last bit first - I have a single three port valve and a
single pump (Y plan I reckon).

Replace the valve head and the time-switch/programmer.
Check for water leakage around the 3 port valve and/or the wiring to/on
the wall thermostat (if fitted).



--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

Set Square wrote:

In an earlier contribution to this discussion,
Jon Telfer wrote:

Hi,
I've just tried to turn on the central heating after it being off
all summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working
OK. Any ideas/usual culprits? It was serving the hot water OK.
It's a horstmann controller and it's not a combi boiler system if
that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

We need a few more details about your system - gravity hot water and
pumped CH, or fully pumped? If fully pumped, how many - and what type - of
motorised valve do you have? [Likely either one 3-port valve (Y-Plan) or
two 2-port valves (S-Plan) - see
http://content.honeywell.com/uk/homes/systems.htm]

Seemingly, something which hasn't been used for a while has developed a
fault in the meantime. If it's a gravity hot water system, I would check
the pump. Otherwise, look at the valve(s).

I've taken the controller apart and put some photos online
http://makeashorterlink.com/?F23F249EB

There are various blown components but the most noticeable thing is that
the copper has been melted from the tracks going to output pins 4 and 5.

There's an installation diagram up there too. It's the only installation
method listed by horstmann to contain a three port valve so hopefully it's
OK. Oddly though I have no room thermostat so presumably this controller
wires from pin 4 straight into the valve - is this the culprit, or am I
jumping ahead of myself?

Thanks,

Jon

Jon Telfer wrote:

Going from the last bit first - I have a single three port valve and a
single pump (Y plan I reckon).

Sounds like the valve and cable would be first on the list of things to
check. Cables can get nibbled by unwanted guests. Less likely would be
the room stat and then only if it is the type that has a neutral feed as
well as live in and out.

Time to get the multimeter out!

If it looks like it is just the programmer that has decided on an early
retirement (with extreme prejudice), then you can wire it out, and rely
on the tank and room stats for control until you get a new one.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In an earlier contribution to this discussion,
Jon Telfer wrote:

Set Square wrote:

In an earlier contribution to this discussion,
Jon Telfer wrote:

Hi,
I've just tried to turn on the central heating after it being off
all summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working
OK. Any ideas/usual culprits? It was serving the hot water OK.
It's a horstmann controller and it's not a combi boiler system if
that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

We need a few more details about your system - gravity hot water and
pumped CH, or fully pumped? If fully pumped, how many - and what
type - of motorised valve do you have? [Likely either one 3-port
valve (Y-Plan) or two 2-port valves (S-Plan) - see
http://content.honeywell.com/uk/homes/systems.htm]

Seemingly, something which hasn't been used for a while has
developed a fault in the meantime. If it's a gravity hot water
system, I would check the pump. Otherwise, look at the valve(s).

I've taken the controller apart and put some photos online
http://makeashorterlink.com/?F23F249EB

There are various blown components but the most noticeable thing is
that the copper has been melted from the tracks going to output pins
4 and 5.

There's an installation diagram up there too. It's the only
installation method listed by horstmann to contain a three port valve
so hopefully it's OK. Oddly though I have no room thermostat so
presumably this controller wires from pin 4 straight into the valve
- is this the culprit, or am I jumping ahead of myself?

Thanks,

Jon

It's *possible* that there was a fault inside the controller itself -
causing it to self-destruct when you switched the heating on - but it seems
more likely that there was a short in the valve actuator. Unless you can rig
up a means of testing the actuator on its own, the only safe solution is to
replace both it and the controller. If you replace *just* the controller,
and there *is* a fault in the actuator, you stand to write off the new
controller.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

In message , Jon
Telfer writes
Set Square wrote:

In an earlier contribution to this discussion,
Jon Telfer wrote:

Hi,
I've just tried to turn on the central heating after it being off
all summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working
OK. Any ideas/usual culprits? It was serving the hot water OK.
It's a horstmann controller and it's not a combi boiler system if
that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

We need a few more details about your system - gravity hot water and
pumped CH, or fully pumped? If fully pumped, how many - and what type - of
motorised valve do you have? [Likely either one 3-port valve (Y-Plan) or
two 2-port valves (S-Plan) - see
http://content.honeywell.com/uk/homes/systems.htm]

Seemingly, something which hasn't been used for a while has developed a
fault in the meantime. If it's a gravity hot water system, I would check
the pump. Otherwise, look at the valve(s).

I've taken the controller apart and put some photos online
http://makeashorterlink.com/?F23F249EB

There are various blown components but the most noticeable thing is that
the copper has been melted from the tracks going to output pins 4 and 5.

There's an installation diagram up there too. It's the only installation
method listed by horstmann to contain a three port valve so hopefully it's
OK. Oddly though I have no room thermostat so presumably this controller
wires from pin 4 straight into the valve - is this the culprit, or am I
jumping ahead of myself?

This is not due to a programmer fault

it's a short circuit somewhere else which has taken out the tracks on
the programmer pcb. It has not died of old age

unless you find the problem, you will have the same problem happening
next time

--
geoff

Jon Telfer wrote:

Hi,
I've just tried to turn on the central heating after it being off all
summer and there was a flash/bang/release of magic smoke.
I've not made any changes to the system since it was last working OK.
Any
ideas/usual culprits? It was serving the hot water OK. It's a horstmann
controller and it's not a combi boiler system if that's any help.

TIA + not looking forwards to tomorrow's shower,

Jon

Problem Solved!
I changed the actuator from the mid position valve and the controller. I
checked the actuator out with my multimeter but couldn't identify any
differences to connections to wires coming in and out (by that I mean I
tested the resistance between all wires and all were high) but I did think
that the mechanism was rickety enough to have a connection between the
electrical side of the manual open lever and the earthed metal case.
Worryingly it was all dead when I first turned it on - the fuse in the
plug that was powering the whole shebang had blown along with the mains
tripswitch.

Thanks to everyone that contributed - this was the first "disaster" in the
new house.
Should any of you need any molecular biology help then drop me a line.

Jon