Anyone taken a Keston C36 "hydroblock" pump + diverter valve assembly
apart and have any idea whether one can do anything for a stuck diverter
valve (short of shelling out around £320 on a new unit!)? That seems to
be the problem on one of these beasts I was looking at yesterday - the
actuator arm the stepper motor operates seemed seized, although googling
suggests a common problem is a capacitor that drives the stepper motor
(presumably phase-shifting, like an induction motor run capacitor) so I
thought I'd try that first in case I'm missing something stupid and that
does the job.

So Q2 does anyone know what this "capacitor" actually comprises?

The capacitor bit is 0.15uF 630VAC 400VDC, looks like polyester or mylar
film, but it's said to have resistors embedded in the heatshrink of the
leads and indeed one can see evidence of them (why two?) at
http://www.gasboilerparts.co.uk/prod...pacitor--was--
c10c418000-.html
and it's described as an R-C assembly at http://www.heatingspares.com/
k4a.html

Just that over 10 squid seems a lot for something that probably isn't the
problem.


--
John Stumbles -- http://yaph.co.uk

Time flies like an arrow
Fruit flies like a banana
Tits like coconuts

On Thursday, November 22, 2012 1:47:50 PM UTC, YAPH wrote:
Anyone taken a Keston C36 "hydroblock" pump + diverter valve assembly

apart and have any idea whether one can do anything for a stuck diverter

valve (short of shelling out around £320 on a new unit!)? That seems to

be the problem on one of these beasts I was looking at yesterday - the

actuator arm the stepper motor operates seemed seized, although googling

suggests a common problem is a capacitor that drives the stepper motor

(presumably phase-shifting, like an induction motor run capacitor) so I

thought I'd try that first in case I'm missing something stupid and that

does the job.



So Q2 does anyone know what this "capacitor" actually comprises?

http://www.wima.com/EN/mkp10.htm

could you remove the insulation on the resitors then you'd know what value they are, might be able to test them and the capacitor too when seperated, the cap shouldn't be more than a couple of quid or so.

this might be suitable

http://onecall.farnell.com/wima/mkp1...0255?Ntt=mkp10






The capacitor bit is 0.15uF 630VAC 400VDC, looks like polyester or mylar

film, but it's said to have resistors embedded in the heatshrink of the

leads and indeed one can see evidence of them (why two?) at

http://www.gasboilerparts.co.uk/prod...pacitor--was--

c10c418000-.html

and it's described as an R-C assembly at http://www.heatingspares.com/

k4a.html



Just that over 10 squid seems a lot for something that probably isn't the

problem.

Yep.






--

John Stumbles -- http://yaph.co.uk



Time flies like an arrow

Fruit flies like a banana

Tits like coconuts

On 22/11/2012 13:47, YAPH wrote:
Anyone taken a Keston C36 "hydroblock" pump + diverter valve assembly
apart and have any idea whether one can do anything for a stuck diverter
valve (short of shelling out around £320 on a new unit!)? That seems to
be the problem on one of these beasts I was looking at yesterday - the
actuator arm the stepper motor operates seemed seized, although googling
suggests a common problem is a capacitor that drives the stepper motor
(presumably phase-shifting, like an induction motor run capacitor) so I
thought I'd try that first in case I'm missing something stupid and that
does the job.

So Q2 does anyone know what this "capacitor" actually comprises?

The capacitor bit is 0.15uF 630VAC 400VDC, looks like polyester or mylar
film, but it's said to have resistors embedded in the heatshrink of the
leads and indeed one can see evidence of them (why two?) at
http://www.gasboilerparts.co.uk/prod...pacitor--was--
c10c418000-.html
and it's described as an R-C assembly at http://www.heatingspares.com/
k4a.html

Just that over 10 squid seems a lot for something that probably isn't the
problem.



That value and your description suggests this is for transient
suppression, and to be honest it's unlikely to be big enough to be a
phase capacitor.

It's more likely an induction motor:
http://en.wikipedia.org/wiki/AC_moto...apacitor_motor

Is there not a much larger capacitor there?

In message , YAPH
writes
Anyone taken a Keston C36 "hydroblock" pump + diverter valve assembly
apart and have any idea whether one can do anything for a stuck diverter
valve (short of shelling out around £320 on a new unit!)? That seems to
be the problem on one of these beasts I was looking at yesterday - the
actuator arm the stepper motor operates seemed seized, although googling
suggests a common problem is a capacitor that drives the stepper motor
(presumably phase-shifting, like an induction motor run capacitor) so I
thought I'd try that first in case I'm missing something stupid and that
does the job.

Better give me a ring tomorrow morning, I'll ask Max


--
geoff