Radiator TRV's

coffeehound

BooJewels said:

Thanks @coffeehound - that was what I was thinking to try, as I think it's higher than my previous boiler.   I know how to change that, the engineer did show me - it's a digital panel. 

It makes sense - as if the water is cooler hitting the radiator, it can't get quite as hot to start with and should therefore stay on longer at a more modest temp.  I'll try 5C first and see if it makes a difference.

Yes it calms everything down and makes it less of a rollercoaster ride.  One thing to be aware of, though, is that if you have a hot water tank, the flow temperature setting needs to remain higher than the tank's thermostat setting, e.g. 60 ℃.  

But with a combi, you can set the flow temperature to whatever you want.  The lower it is set, the more efficiently the boiler will run the heating.

BooJewels

plumb1_2 said:

BooJewels said:

. 

It makes sense - as if the water is cooler hitting the radiator, it can't get quite as hot to start with and should therefore stay on longer at a more modest temp.  I'll try 5C first and see if it makes a difference.

5 c    Is a no 
best to make your own post Boojewels

Sorry, but your bit in bold doesn't make sense.

I apologise to the OP if I derailed their thread, but I thought they were closely enough related, that answers to one might help the other.  And I don't see it saying moderator under your name either.

Bendy_House

Verb said:

Thanks "BooJewels & Bendy_House"

Yes my main issue is the constant 1 extreme to the other. Controlling the heating at the boiler is not an option as I have a large downstairs space and the boiler is set up to accommodate that.

I think I would rather a constant temp on the radiator be better than red hot or off.

I've since read that my TRVs where 10 years out of production, 6 years ago so it may be time to replace the 3 radiators and TRVs.

Is there any option to replacing the TRV head for a manual head??

Yes, and it's a cheap thing to try, so probably worth it just to see if it suits you.

There are two basic types - you can get actual manual replacement heads that take the place of TRVs, and these screw down and then have an adjustable rotating knob on them. Or there are what's called 'replacement TRV caps' or similar, and these are actually designed for securely shutting off TRV valves if you want the rad removed for decorating, for example. So these just screw down tightly, and they hold the 'pin' pressed down so they are fully offski. However, there's nothing to stop you unscrewing them a bit so that they effectively act as adjustable manual controls.

Eg: https://www.screwfix.com/p/drayton-radiator-valve-cap-white-5-pack/5649r

You need to check they'll fit - ie ideally find out the make of TRV you have (photo?).

This isn't the ideal solution, tho' - TRVs are the best choice. It might be that yours are just a bit sticky in operation, so when they've been shut off due to the room's heat, they are reluctant to open again when they should.

BooJewels

coffeehound said:

BooJewels said:

Thanks @coffeehound - that was what I was thinking to try, as I think it's higher than my previous boiler.   I know how to change that, the engineer did show me - it's a digital panel. 

It makes sense - as if the water is cooler hitting the radiator, it can't get quite as hot to start with and should therefore stay on longer at a more modest temp.  I'll try 5C first and see if it makes a difference.

Yes it calms everything down and makes it less of a rollercoaster ride.  One thing to be aware of, though, is that if you have a hot water tank, the flow temperature setting needs to remain higher than the tank's thermostat setting, e.g. 60 ℃.  

But with a combi, you can set the flow temperature to whatever you want.  The lower it is set, the more efficiently the boiler will run the heating.

I don't have a tank, so the temp purely alters the water in the radiators.  Plus a separate control for hot water of course,

I've reduced it by 5°C and it already sounds calmer - it didn't make a big roar getting going after some time off.  I'll see how it fares after some more time.  Thank you.