C/H doesn't work unless H/W is on.

[johnscales]

Been having a discussion with a colleague and have come to the conclusion that my CH/HW system must be faulty. For years I've not been able to set my CH to come on separately from my HW. The Programmer has the function of setting individual times for both but the CH will only come on so long as it's within the window of the HW being on.
I don't have a room thermostat, every rad has a TRV attached.
As far back as I can remember this has always been the case and i've lived in the property from new.
Q's

1) Is this normal (i'm guessing not)
2) Whats the best method to fix (assuming it's not normal)

Thanks

 

[kevplumb]

what system do you have ?
View media item 11148 View media item 11149
any of these ?
usually near the cylinder and/or pump

 

[johnscales]

Wish I were t home. Definitely not the bottom one.

 

[johnscales]

and if i'm honest (and i'm in the boiler room daily) I can't say i've seen the top pic either.

 

[johnscales]

Actually. There is definitely a box with a black leccy wire wire going into it like in the bottom pick but it defo doesn't have a three pipe junction coming out of it.
What is the reason behind the question?

 

[Agile]

Actually. There is definitely a box with a black leccy wire wire going into it like in the bottom pick but it defo doesn't have a three pipe junction coming out of it.
What is the reason behind the question?

There are many different configurations of heating systems.

We dont know which one you have and you could even have a non standard one done by a DIer etc.

Your system might support what you want but then it might not and need modification.

You can either provide the information or call a professional to advise you.

It sounds as if you have a single two port motor valve.

Tony

 

[johnscales]

Thanks Agile.
Does that mean then, going back to my original question, that my ch/hw system is working as it should?

 

[kevplumb]

if it's a gravity system then yes

if it's pumped then no

 

[johnscales]

Not to purposely mess with your answer Kevplumb but I have "gravity feed to the HW cylinder and pumped CH" so a bit of both no and yes by all accounts.

Having done some more reading on these honeywell 2 port motor valves I'm satisfied that things are working as they should.

 

[kevplumb]

you have what is generally termed a gravity system

so you can't have heating without hot water