Poor heat output from radiators

[king of pipes]

No its not unsual its let's the boilers pump still have a circuit should the rad TRVS close or get turned off when the boiler reaches its set tempreture and switches off the pump continues to run to reduce the tempreture in the heat exchanger the bypass in the boiler is only a small pipe so not so good works better having a external one fitted , you could try replacing it or even better move it near the boiler personally I would still say your boiler is undersized .

 

[Stigster]

Why is a 3 bar pressure relief valve being used as a bypass, if that is what it is in your picture?

Edit - I see that it is a bypass valve. Haven't seen that type used round my way before.

 

[ShaunCorbs]

Why is a 3 bar pressure relief valve being used as a bypass, if that is what it is in your picture?

Edit - I see that it is a bypass valve. Haven't seen that type used round my way before.

honeywell bypass mate

 

[srowe]

So I've just had an engineer out to service the boiler and talk about the issues I'm having. His opinion is that there is a flow problem and the system needs a power flush. It may also need an additional pump on the return given the size of the system but that should be reassessed after the system has been cleaned out.