Radiators dont heat up very well

emerald21

Hi, We have a Worcester Bosch condensing boiler which is about 2years old now. However although we get hot water from it our radiators barely get warm. The radiators are the original ones from when the house was built which is about 30 years ago. Do we need to replace them or do they just need flushing out or whatever is done. Its not the fact they might need bleeding cos thats been done. Thank you

keystone

There are all sorts of reasons why this could be happening. What is your boiler model/type? Do the rads "barely get warm" at the top or at the bottom? Does the pipework get hot and the radiators not? You may have a faulty three port (Y plan) or zone valve (S plan) or internal divertor valve if you have a combi. You may have crud in the rads. You may have a pipework blockage preventing circulation and if its an older system still using an F&E tank in the roofspace the pipework associated with that would be the first place I'd be looking for a blockage.

TBH you really need to get someone in to look at it but in the meantime if you can provide some further detail about your system we may be able to narrow it down a bit for you.

Cheers

Freddie_Snowbits

To me it sounds as thought the system needs bleeding and refilling. Do the radiators feel warm at the top, but cooler near the bottom? This means the radiators need bleeding. If this is a closed system, there will be a pressure dial somewhere near your boiler and I think the website for Worcester Bosch has detailed instructions on how to fill and pressurise your system. You need to do this about every 6 months

keystone

emerald21 wrote: »

Its not the fact they might need bleeding cos thats been done.

Freddie_Snowbits wrote: »

To me it sounds as thought the system needs bleeding.............

Eh? Did I miss something?

Cheers

emerald21

Freddie_Snowbits wrote: »

To me it sounds as thought the system needs bleeding and refilling. Do the radiators feel warm at the top, but cooler near the bottom? This means the radiators need bleeding. If this is a closed system, there will be a pressure dial somewhere near your boiler and I think the website for Worcester Bosch has detailed instructions on how to fill and pressurise your system. You need to do this about every 6 months

No they are warm at the bottom and cold at the top and thanks for replying

keystone

Could you say a little more about your system? Boiler type/model? Tanks in roof with standard HW cylinder in airing cupboard? Any motorised valves? No tanks in roof but unvented cylinder? No cylinder at all? etc etc etc. Thanks

Cheers

paulsad

Putting a new boiler on with old rads can cause problems eventually as crud/rust from the old rads/pipes can clog the boiler. You may need this checking and flushing and a rust inhibitor added. How is you water pressure assume you've got good pressure at the guage 1.5 - 2 bar.

emerald21

keystone wrote: »

Could you say a little more about your system? Boiler type/model? Tanks in roof with standard HW cylinder in airing cupboard? Any motorised valves? No tanks in roof but unvented cylinder? No cylinder at all? etc etc etc. Thanks

Cheers

According to the instruction manual its a Worcester Bosch greenstar either 24 i junior or 28 i junior. No cylinder in airing cupboard. Dont know about motorised valves. I know how to get the pressure back up to normal when it looses it usually in the winter on the coldest day possible. Running hot tap starts it going but obviously dont want to leave it running all the time. I dont know much about boilers etc and husband knows even less . Also i dont think the thermostat in the living room is connected to it properly. Had old boiler in for about 30yrs no problem but have had nothing but trouble with this one. I dont mind paying a fair price obviously but i dont want to be ripped off as none of us do, do we ?

emerald21

paulsad wrote: »

Putting a new boiler on with old rads can cause problems eventually as crud/rust from the old rads/pipes can clog the boiler. You may need this checking and flushing and a rust inhibitor added. How is you water pressure assume you've got good pressure at the guage 1.5 - 2 bar.

As far as i know the pressures ok at the moment but then the only time we have it on is when bathing as its Summer. Have had to open with a key underneath a few times to let the pressure build up again. No mention of having new radiators when having boiler done,some other guy came with him to do the plumbing part and we had to get an electrician in to presumably do what he needed to do,but as i said in last post i dont think the thermostat in living rooms is connected for it to work properly. So as the radiators dont get hot it sounds like it definatly needs flushing or at worse new radiators Hubbies disables so need to get it sorted by this coming winter.:(

brig001

How warm is the house? I can't imagine needing the radiators hot at this time of year to be comfortable. Maybe the room thermostat has decided the room is warm enough and switched the radiators off. Also, if the house is nearly warm enough, it should only make the radiators warm, not hot.

keystone

emerald21 wrote: »

According to the instruction manual its a Worcester Bosch greenstar either 24 i junior or 28 i junior. No cylinder in airing cupboard. Dont know about motorised valves.

OK if the cylinder has been removed its a combi boiler then. How big is the house? If you have no cylinder you will have no obvious motorised valves so we can forget these but the boiler will have its own internal diverter valve. ?

I know how to get the pressure back up to normal when it looses it usually in the winter on the coldest day possible.

You shouldn't worry about small pressure fluctuations which will happen anyway when the water in the system heats up and cools down.

When the Running hot tap starts it going but obviously dont want to leave it running all the time.

A combi heats water on demand so when you open the hot tap the boiler fires up, heats the water and delivers it to you.

Also i dont think the thermostat in the living room is connected to it properly.

Why do you think that?

So a couple more questions about your heating. Are your radiators fitted with thermostatic valves? Something like this:



or this:



If so what number on the dial are they set to?

Had old boiler in for about 30yrs no problem but have had nothing but trouble with this one. I dont mind paying a fair price obviously but i dont want to be ripped off as none of us do, do we ?

Indeed.

Cheers