worcester bosch 15/19 problem

[am609]

Oil fired,w/b 15/19 aprox 12years old,symptoms are dhw very warm,and rads on when c/h switched off.At night when boiler is off no h/w in the morning usually heatslave 10 gall heatbank tank gives reasonable h/w.It appears that pump is running all the time (instead of a period of pump overun). Is this a thermostat prob giving a signal for the pump to thinking its high limit stat has activated.

 

[wilhelm]

diverter valve sticking?

i dont rem heatsalve pump having overun, but hey, read the manual at last resort.

 

[am609]

Pump runs all the time,until boiler fuse is pulled out,manual says it has a pump overun,and troubleshooting guide is mostly for burner problems and does not cover this issue.my day job is repairing aircraft engines so not 100% familiar with boilers

 

[wilhelm]

yes page 3

well diverter valve. put ch on only....does lever move? or after waiting a minute and turning off at fused spur can you hear motor returning under spring return?

 

[am609]

diverter v/v only moves when fused spur pulled,when ch operated only and dhw demanded no movement in v/v.I asume it should move when dhw is required?

 

[wilhelm]

no movement for hot water. as it is that position until heat tank thing up to temp, then movement for ch.

try ch only. turn hw off.


pump running all time points to div valve microswitch probs. so head change.

although....i had one recently ....and it was danfoss tp programmer prob.

 

[am609]

ran dhw till cold turned hw off. when ch switched on, again no movement in v/v,as before v/v only returns under spring tension when switched off at spur

 

[wilhelm]

ok children....as the night progresses....things can get confusin'.....


sounds as if you have "movement" what i should have said is the little silver lever "goes slack"

so im going to say change the head of the diverter valve. could be honeywell .silver box. or drayton . plastic.

as an aircraft injin fittrer you should p*ss it.


edit...yep diverter valve change the lot. as its letting by as well.
just looked at wiring diagram. yep "t osser" is the word.

ah well.....

 

[am609]

silver lever is very slack, so default position on this v/v (ie not energised) favours dhw?

 

[wilhelm]

yes, and the sympton of pump on all time points to microswith in diverter valve. and as u said about ch getting hot when off, points to ball letting by.

so change the diverter valve . complete.



............

 

[am609]

silver box type,ACL appliance components ltd, so trip to local plumb centre for replacement diverter v/v assy?

 

[wilhelm]

are you ex raf? and require orders.?

.............

 

[Agile]

I hope you are better with your aircraft engines than boilers!

From what I have read quickly its not obvious that the boiler thinks the hot water tank is hot enough!

have you confirmed that the tank stat/sensor is operating correctly and showing the boiler that its satisfied?

What CO² percentage should I expect from my RB211 ?

Tony

 

[wilhelm]

i wood surrrrrjest. stats all werking.

and the pump is ticking over cos m/switch is fekked.

..tony.
and i think ive had enough of your rb211

 

[am609]

next installment prob tomorrow night,
remember next time going on hols,I might be the man with the red toolbox who is repairing your aircraft and causing your delay, and
"there are no lay-by's in the sky"!!