Halstead Quattro: Hot water goes off when cold turned on?

[matthewS]

Can anyone assist?,

When I run the hot water all is O.K. until I run the cold water, to which the burner swithces off. As long as I don't run the cold tap the hot water is fine?

Many thanks for any leads to this strange problem.

 

[kevplumb]

normal with low pressure / flowrate

 

[matthewS]

Hi,

Thanks for a speedy response.
The flowrate/pressure hasn't changed and remains high as normal?
Always have been able to run hot with cold without burner switching off?and is the first time this has happend since purchase of boiler?

Any further suggestions greatly appriciated.

 

[Agile]

This problem usually arises because of a cross connection between the hot and cold supplies AFTER the boiler.

This often occurs with joystick taps because the installers did not bother to fit the required non return valves.

If you have any of these move ALL the joysticks to the cold position when not in use.

It can also happen because a fitted or integral non return valve has dirt on the seat and is letting the cold into the hot circuit. This effectively short circuits the boiler which then fails to detect a demend for hot water.

Tony Glazier

 

[matthewS]

Many thanks for your response,

Have now cured the problem by fitting a new diverter valve.
Which would make sense from your feedback.

Thanks again.

 

[Agile]

In that case, in spite of what you said before, the hot water flow rate must have reduced when you used cold water at the same time.

Only the diaphragm would need to be changed in the diverter valve.

Tony