hot radiators

[redblues]

hi there i have a thorn m44 central heating system the problem i have alway had is when the boiler is running with wall thermostat switched off the upstairs radiators stay hot,so have to close radiator valves to keep them cold when not needed.have lived with this for years but after finding this site wondered if anyone has any suggestions.thanks

 

[David937]

I have heard this is because if convection if the cylinder is heated by gravity, on my Grandads old system thy had a Glowworm back boiler and whenever hot water was on the upstairs radiators used to get hot, it was good in summer because we could have the bathroom radiator on to dry towels etc.

Unfortunately because his house is a council house the boiler has now been replaced with a..... Ideal Isar HE30

 

[gavinda]

need to know a bit more about the system. , fully pumped or gravity?

could be a mid pos/zone valve let by, a failed anti gravity valve or just the age of the system starting to show.

 

[simond]

I have heard this is because if convection if the cylinder is heated by gravity, on my Grandads old system thy had a Glowworm back boiler and whenever hot water was on the upstairs radiators used to get hot, it was good in summer because we could have the bathroom radiator on to dry towels etc.

Not really. Many houses still have gravity hot water off an old style boiler, but this does not mean that the upstairs rads come on..

Chances are that there is a reverse return going on due to the return being piped up incorrectly or, such as suggested earlier, a failed or missing anti gravity valve.

 

[reneel]

unlikely to be a faulty mid position valve. the zone valve (2 port) if used may be letting by; but only if the upstairs has a different zone to the downstairs!!!

probably reverse-circulation (the last tee rule not used)!! or a faulty anti gravity valve !

 

[David937]

I have heard this is because if convection if the cylinder is heated by gravity, on my Grandads old system thy had a Glowworm back boiler and whenever hot water was on the upstairs radiators used to get hot, it was good in summer because we could have the bathroom radiator on to dry towels etc.

Not really. Many houses still have gravity hot water off an old style boiler, but this does not mean that the upstairs rads come on..

Chances are that there is a reverse return going on due to the return being piped up incorrectly or, such as suggested earlier, a failed or missing anti gravity valve.

Well we learn new things everyday, I thought I might be correct because that's what we were told by the heating people.

 

[redblues]

hi all thanks for your thoughts much appreciated