hot water does not work without central heating

[bluesky]

just installed a megaflo cylinder with a baxi system boiler, the problem is the hot water cannot work without turning on central heating, i suspected there is something wrong with the DHW valve, however it is fine, when i turned on the DHW, the temperature changes from 40 to 80 very quickly and then boiler stops, i think it is because the water part is blocked and then put in an air vent, but still not working, anyone has this kind of experience?

cheers

 

[Gray0689]

Have you piped it as a s pan (zone valves)????

 

[SimonJohns]

Does the controller know that the has and ch is independent

 

[frankjames]

Did you ever resolve this as i had a similar problem recently ?

 

[hammers4spanner]

where have you located zone valve??

 

[Barry98]

Good to see the search button is used before repeating same question . Wish newbies would