Why 1 radiator without TRV?

[messy69]

I have a Combi/Radiator heating system with 8 radiators around the house, no room has a wall thermostatic control.

All but the bathroom has TRV's fitted.

Is there a reason the Bathroom does not have a TRV as I wish to fit one instead of having the std valve slightly open which keeps the heat at a minimum?

 

[bluemooner]

You need to have one raiator without a TRV so the boiler can get some flow. Usually the one near the thermostat.

If they all had TRVs they could all close and there would be nowhere for heat to go.

Are you sure there isn't a wall thermostat ?

 

[messy69]

No definately no wall thermostat.

As I need to keep the Bathroom rad valve open as you say, is it ok to have it only slightly open?

I dont want to keep it fully open as the room gets too hot.

Of all the radiators the bathroom one is the closest to the boiler.

Does it not keep the boiler operating/switching on though if the valve is open constantly?

 

[ollski]

No definately no wall thermostat.

Does it not keep the boiler operating/switching on though if the valve is open constantly?

Yes it will do if the heating cannot be turned off at the boiler, but I would guess you have a programmer on there.

 

[messy69]

The boiler does have a programmer.

This seems a very un-efficient way of running a system though.

The boiler will keep coming on all the time when say its a hot day, all the other radiators with TRV's will be closed as the temperature is high but as the non trv radiator has the valve open the boiler will keep heating the room - which is whats happening.

The boiler is running as per the program and when all other rooms/radiators reach the level set they switch off, but the bathroom keeps getting heated.

This seems to me a waste of electric/gas/heating and my money!!

Is this how all Combi/Radiator systems operate?

 

[bluemooner]

Sounds like you need ............... er......... a thermostat ?

 

[messy69]

Right I need a thermostat, presumably fitted into the bathroom as this is where I have my problem.

1 Is it ok to fit one in a bathroom

2 Is it a job I can handle myself being above average on the DIY scale or do I need a "professional"

And as a result - If I have one fitted, to the bathroom am I presuming it will then say on a hot day, all TRV's are closed, programmer is switched on, bathroom thermostat is closed as set low - the boiler wont switch on?

 

[bluemooner]

Well the way my heating system works is with a timer that turns the system on and off when I want it to, and a thermostat that tells the boiler to give it some, until my prefereed temperature is reached.

I have TRVs on all but one of the radiators so I can set different levels of heat in each room. The only one without a TRV is in the hall as it should help get the air space up to the correct temperature at which point the thermostat tells the boiler to calm down.

I find it a bit strange that you have a heating system without a thermostat, but then again there could be a very good reason for that.

Best bet is wait for a reply from a 'proper' plumber rather than an over zealous DIYer !!

 

[Skattie]

When warm it should shut the boiler off - regardless off what ur TRV's are doing.
If your thermostat is in the right place and set correctly you shouldn't need any TRV's
When running your boiler needs a full circuit of water.
Some boiler's do have a by-pass, I believe, that will come into action if all rads are closed.

 

[ollski]

you can't have a room thermostat in the bathroom, it would turn your heating off whenever anyone ran a bath in the winter!, swap the trv from your hall rad and fit the thermostat in there. Fitting instructions will be in the boiler manual and will just be a standard 3 core cable run to wherever you decide to fit your stat.

 

[messy69]

My boiler is not firing / gas burning all the time when my programmer is switched on when say my TRV's are closed but it is on "making a working" noise and then fires up / burns gas every so often to presumably heat the Bathroom where no TRV is fitted. But it is making a noise rather than when the programmer is off.

I hope as Bluemooner states a "Proper plumber" can help as this is doing my nut............ please "proper plumbers what do I need to do.............

 

[messy69]

Thanks "ollski", if I do as you say will the Boiler then not run at all if all TRVs and Thermostat are closed ie not even switch on ready for when heat may be required?

I will dig out the manual and see how it fits.

Will check back later to see what anyone else recommends

 

[nstreet]

If your thermostat is in the right place and set correctly you shouldn't need any TRV's

Not quite true IMO, you wouldn't necessarily want the bedrooms at the same temp as the living room, hence the fitting of trv's. It's also a bit wasteful on energy not to have them.

Its very unlikely that all the rooms in or house have the same thermal efficiency and will all loose heat at the same rate. The room you choose to put the stat in could be north facing and chill quicker. Whereas the lounge may be south facing and be a lot warmer. You would end up cooking in the lounge to maintain a satisfactory temp where the thermostat is. TRV's give that little extra control and comfort.

 

[ollski]

Thanks "ollski", if I do as you say will the Boiler then not run at all if all TRVs and Thermostat are closed ie not even switch on ready for when heat may be required?

I will dig out the manual and see how it fits.

Will check back later to see what anyone else recommends

Room thermostat is simply a temperature controlled power switch, when its satisfied it breaks the circuit when its calling it makes it and your system will then run to the trv's and the bypass rad in the hall will cut out when it warms your room stat in your hall up to the set temp. The room thermostat will be needed to set high enough that it doesn't cut out the trv's before they get to the set temperature of course.