Worcester Combi CH By-Pass

[DaveyJones]

Existing CH system is a Worcester 280 Combi with TRVs on all rads except the bathroom. When questioned why, the installer said one rad' needed to be uncontrolled to act as a "bypass".
This results in a very hot bathroom necessitating the lockshield be turned almost off to achieve a sensible temperature - which to my mind negates its effect as a bypass.
As this radiator is now looking very sad and dilapidated, we want to replace it with a towel warming radiator.
I therefore propose to fit a somewhat smaller BTU rated towel rad' to allow the lockshield to be "more open" (the existing rad' is rated about 2200 BTU but the initial design called for a rating of only 1300 BTU (it's a tiny room and my recent calculations confirm this figure - I suspect the installer fitted a considerably bigger rad' because he had it spare from another job).
My question is.....having examined the manual for the boiler, I see there is an integral "CH Bypass" fitted across the flow/return pipes so can I disregard the installers comments and fit a TRV and rely on the boilers internal bypass?

 

[Terrywookfit]

Do you have a room stat fitted?
The radiator fitted in the same room as the stat is normally used as the bypass.

 

[clf-gas]

The use of a radiator as a bypass is foolhardy in my opinion, as you have pointed out its all too easy for this rad to be closed off.
What your proposing sounds an amicable solution to your overly warm room

 

[bengasman]

I always stick two lockshields on the rad in the room with the roomstat, it assures the working of the stat, and removes the need for a bypass.
As long as you have one rad that is always open, no matter where the rad is, you will be fine without a separate bypass.

 

[DaveyJones]

Thanks all, for the responses.
There's no room 'stat anywhere, however, since my original post I've since read the '280's Installation Manual which does state that there MUST be an uncontrolled rad' somewhere in the loop to act as a by-pass.
So, a properley sized towel rad' with (as suggested) two lockshields it will be.
Thanks again.