hot radiators

[barneyboytina]

hi
my parents heating comes on down stairs when just the water should be heating. it seems to be flowing from the return pipe from the cylinder tank as this pipe is the hottest pipe on the radiators. when the heating system is on it is the other pipe that is hottest. some one told me that there should be a check valve on the return pipe where the central heating and the hot water return pipes join, is that correct or is it just a qwerk and they have to continue to turn off the radiator at the taps?
any advice would be appreciated.
BBT

 

[45yearsagasman]

MORE INFO ON SYSTEM REQUIRED!!!!!!!!!!!!!!! HOW MANY MORE TIMES WILL THIS QUESTION BE ASKED? Rant over, feel better now.
No one possesses a crystal ball, so post a pic or describe the system and all its controls.

 

[barneyboytina]

sorry about that.
its a baxi floor standing boiler that feeds a cylinder on the ground floor. there are 2 2 port valves under the house one for the heating one for the cylinder. i checked these and they appear to work ok (i put my hand on the flow side and checked if they allowed hot water through when in the off position).
when the boiler was on to heat the cylinder the flow pipe got hot first but as the return pipe started to heat up so did the ground floor radiator return pipe thus making the radiator get warm.
the pump was on speed setting two and is in the flow pipe.
there is a pressure relief valve after the pump but before the 2 port valves.
the cylinder used to be upstairs and gravity fed for the hot water but my parents got it moved to down stairs when they had alterations done.
they are reluctant to get the plumber back to look at this problem even though it seems to have occured since the change was made as being on pensions they cannot afford much, thats why they have asked me to enquire as to the possible cause of the problem before action is taken.
the work was done at the beginning of last winter so they did not notice the fault until a couple of months ago. at first i thought they were setting the programmer wrong but this turned out not to be the case.

 

[45yearsagasman]

From what you say the system has been converted to fully pumped S plan.
I assume that the zone valves are new and not passing to heating when the hot water is on.
My first thought is that your plumber has piped the system up incorrectly and you have reverse circulation. For a layman, it is sometimes quite difficult to understand the reasons for this, but it is to do with the position of the CH and cylinder returns on the main return to the boiler. A decent heating engineer should be able to suss it out for you, but the mistake would have been made by the original plumber, so try him first.

 

[barneyboytina]

Hi Pete
Thanks for the reply.
the valves are not bleeding through and the flow is in the correct direction but the cylinder return is tee'd into the radiator return pipe within two meters of the cylinder and you can feel the heat flowing up the return pipe.
Te original plumber is no longer trading (i don't know if he retired or has gone to work for someone else) and my parents are reluctant to get someone in without having an idea of what is up as the first plumbers bill was quite hefty and they are both on crap pensions (thanks to the stock market crash 6 months prior to them both retiring and halving their pension pot).
if i can get an idea what may be up i can ask for a guide price to have it sorted for them.
regards
craig