No hot water

[Padam442]

Need help. My fully pumped system won't switches on when it's calling for just hot water. To get hot water, both hot water and central heating has to be on at the programmer. If only HW is on at programmer, it will not come on. I am not sure is it programmer or 2 port valve.

 

[craigy]

Can you describe what heating stem you have in more detail? You say fully pumped system an d mention a 2 port valve. So I don't cause offence, I'll talk assuming your a homeowner with basic knowledge. How many pipes are attached to the two port valve? The problem sounds like you actually have a Y-plan system, this is a 3port valve with 3 flow options, heating only, hot water only, or both. When C/H and H/W are both demanded the valve sits in what is called the mid position allowing the hot water to be pumped to both the H/W cylinder and the radiators. This would explain why you can only get hot water when both are selected. Mid position valves should as a default, position the diverted to allow hot water unless asked other wise.
Most likely cause is faulty valve motor, replace it.
.

 

[Deleted member 64964]

He could also have a two port system and the hot water two port is knackered and in the open position hence only working when the heating is on.

 

[craigy]

He could indeed thermo man. Guess we will only know when he/she gets back on to reply. If the h/w 2 port is stuck open then if he turned just the c/h on the programmer and not the h/w too it should heat up the water still.

 

[Deleted member 64964]

He could indeed thermo man. Guess we will only know when he/she gets back on to reply. If the h/w 2 port is stuck open then if he turned just the c/h on the programmer and not the h/w too it should heat up the water still.

Yeah it should your right! We will probably never know lol

 

[Padam442]

I have got 2 port valve. When only HW is on, nothing happens. To get the HW, I have to switch on both HW and CH at my Old programmer (Randall 103). My guess is may faulty programmer.

 

[kay-jay]

did it used to work ok?

 

[Fish marshall]

faulty micro switch on the hw valve head easy way to tell is if the system is off the valve should be closed then when u call for heat on the hw the valve should open
if so you could change the motor head assembly only if its a honey well / danfoss
if not u may need to change the complete valve
or if you are good at soldering a micro switch is only 6-7£

 

[Deleted member 64964]

I have got 2 port valve. When only HW is on, nothing happens. To get the HW, I have to switch on both HW and CH at my Old programmer (Randall 103). My guess is may faulty programmer.

Do you get hot water if you only have heating on?