Bosch dishwasher problem: solenoid voltage?
 

Bosch dishwasher giving a "Check Water" light. Water supply is fine.
Standard solenoid valve on the inlet supply, low resistance on the (240
volt) solenoid. Power it up, and only seeing 85 volts AC on the solenoid
supply, which seems odd to me.

Does that sound like the problem, or do these solenoids operate on lower
voltage?

TIA

Bosch dishwasher problem: solenoid voltage?
 

On 01/12/2011 12:11, Newshound wrote:
Bosch dishwasher giving a "Check Water" light. Water supply is fine.
Standard solenoid valve on the inlet supply, low resistance on the (240
volt) solenoid. Power it up, and only seeing 85 volts AC on the solenoid
supply, which seems odd to me.

Does that sound like the problem, or do these solenoids operate on lower
voltage?

TIA

Perhaps it is switched on by a triac on the PCB. Triac is buggered, and
acting as a halfwave rectifier. Is there any reading on the DC range of
your meter?

--

Graham.

%Profound_observation%

Bosch dishwasher problem: solenoid voltage?
 

On 01/12/2011 14:40, Graham. wrote:
On 01/12/2011 12:11, Newshound wrote:
Bosch dishwasher giving a "Check Water" light. Water supply is fine.
Standard solenoid valve on the inlet supply, low resistance on the (240
volt) solenoid. Power it up, and only seeing 85 volts AC on the solenoid
supply, which seems odd to me.

Does that sound like the problem, or do these solenoids operate on lower
voltage?

TIA

Perhaps it is switched on by a triac on the PCB. Triac is buggered, and
acting as a halfwave rectifier. Is there any reading on the DC range of
your meter?

Very good thinking. I was wondering about checking the DC while walking
the dogs. Unfortunately to get at the board I'll have to disconnect the
chamber from the base and the pumps, but that theory gives me a good
reason to try it. I'll check for DC first.

S

Bosch dishwasher problem: solenoid voltage?
 

On Dec 1, 12:11*pm, Newshound wrote:
Bosch dishwasher giving a "Check Water" light. Water supply is fine.
Standard solenoid valve on the inlet supply, low resistance on the (240
volt) solenoid. Power it up, and only seeing 85 volts AC on the solenoid
supply, which seems odd to me.

Does that sound like the problem, or do these solenoids operate on lower
voltage?

TIA


The operating voltage will be marked on it. If it is mains volts, you
could test it by making a tempory mains connection (disconnect it from
machine of course) Then you would know if the valve was OK or not.

Bosch dishwasher problem: solenoid voltage?
 

On 01/12/2011 15:56, harry wrote:
On Dec 1, 12:11 pm, wrote:
Bosch dishwasher giving a "Check Water" light. Water supply is fine.
Standard solenoid valve on the inlet supply, low resistance on the (240
volt) solenoid. Power it up, and only seeing 85 volts AC on the solenoid
supply, which seems odd to me.

Does that sound like the problem, or do these solenoids operate on lower
voltage?

TIA


The operating voltage will be marked on it. If it is mains volts, you
could test it by making a tempory mains connection (disconnect it from
machine of course) Then you would know if the valve was OK or not.

The valve is fine, the system isn't giving the right volts. Not a triac,
just relays so presumably dead relay on board (not so easy to test).

New board, £155 from espares. New machine, £234 from John Lewis. Just
ordering some relays.

Bosch dishwasher problem: solenoid voltage?
 

On 02/12/2011 14:30, Newshound wrote:
On 01/12/2011 15:56, harry wrote:
On Dec 1, 12:11 pm, wrote:
Bosch dishwasher giving a "Check Water" light. Water supply is fine.
Standard solenoid valve on the inlet supply, low resistance on the (240
volt) solenoid. Power it up, and only seeing 85 volts AC on the solenoid
supply, which seems odd to me.

Does that sound like the problem, or do these solenoids operate on lower
voltage?

TIA


The operating voltage will be marked on it. If it is mains volts, you
could test it by making a tempory mains connection (disconnect it from
machine of course) Then you would know if the valve was OK or not.

The valve is fine, the system isn't giving the right volts. Not a triac,
just relays so presumably dead relay on board (not so easy to test).

New board, £155 from espares. New machine, £234 from John Lewis. Just
ordering some relays.

You are suggesting that the relay contacts are high resistance and
consistently has two thirds of the mains voltage across its closed
contacts. This seems unlikely.

Is the solenoid defiantly being switched on by a mechanical relay at
230V? Or is it a solid state relay, in which case low voltage to the
load faults would be more easily explained.


--

Graham.

%Profound_observation%

Bosch dishwasher problem: solenoid voltage?
 

Graham. wrote:


Is the solenoid defiantly being switched on


Belligerent and recalcitrant things, those solenoids!

Bosch dishwasher problem: solenoid voltage?
 

On 02/12/2011 20:50, Graham. wrote:

You are suggesting that the relay contacts are high resistance and
consistently has two thirds of the mains voltage across its closed
contacts. This seems unlikely.

Is the solenoid defiantly being switched on by a mechanical relay at
230V? Or is it a solid state relay, in which case low voltage to the
load faults would be more easily explained.


Good point! See later posting about triacs!