heated towel rail not getting hot.

[johnwig]

the heated towel rail in our upstairs bathroom has over a period of time stopped working. it is a standard through the central heating model with 2 trv at the bottom and a bleed valve at the top left.
The central heating system is non -combi with a multi feed punp in the airing cupboard by the water tank. it has 3 feeds from the pump, 1 downstairs rads, 2 upsatirs rads and 3 hot water.
All rads up and down work fine and have been bled. when i open the towel rail bleed valve it spurts clean water. if i close both valves then no water comes out and if i open/close each valve individually then water spurts out ok so i presume neither are blocked/closed.
if i then keep the bleed valve open for 5 - 10 mins then hot water seems to get through but by the following day it is cold again.
i have tried increasing the pump speed but no improvement.
any ideas please?

 

[bengasman]

it is a standard through the central heating model with 2 trv at the bottom and a bleed valve at the top left.

Nothing standard about that, rads should not have 2 trv's

...with a multi feed punp in the airing cupboard by the water tank.

What is a multifeed pump?

 

[johnwig]

thanks bengasmen for your reply. Firstly a slight error in my description in that the towel rail is as said through the central heating but has 2 adjustable "radiator type control valves" which i presume are inlet /outlet so not actually trv's.
the pump has multi feed written on it. basically there are 3 electric leads going into it, hot water, upstairs rads and downstairs rads as the upstairs and downstairs heating is seperatly controlled.

 

[heatingman]

3 two port valves, towel rad could be plumbed any number of ways.
I reckon some twonk has left it on the old primaries.