Central heating dilemma

dharm999

We have just bought our forever house (well 20 years at least), and amongst the multitude of things that needs to be sorted is the central heating.

The current set up is a traditional potterton boiler, with a hot water tank downstairs, in the chimney that was used by the range in the kitchen. The two cold tanks are in the loft. There are 14 radiators in the house, and the boiler has been serviced regularly, as the house used to be a care home. The pipes for the heating are microbore pipes(?). However some of the radiators are old, probably installed in the 80s, and they don't get hot. They get warm at the top and are cool/cold at the bottom, which, I understand, indicates that they are probably full of stuff. We intend to do a loft conversion later this year, as well as refurbish the kitchen and move the hot water tanks.

My dilemma is what to do with the central heating system. Do i just get the system cleaned out, c£500, and move the hot water tanks? Or do I buy a new boiler, that is more efficient? I have had BG and a local firm around to give me a quote. BG said install a combi, and they would charge c£5k to do that. That would get rid of the tanks, and make the loft conversion simpler, but the house will then have 3 bathrooms, so I dont think that a combi would be the ideal solution, even though there are only 2 of us, going to 3 when our son comes to stay. The local firm originally suggested a system boiler with an unvented tank (?), but after the guy saw that the main supply pipe was 15mm, he suggested a storage combi instead, or upgrading the supply to 22mm to allow them to fit the system boiler.

I am now confused. As a minimum we want to move the hot water tanks, and need to sort out the cold radiators, as the some of the rooms are flippin freezing at the moment, but would it be better to go the whole hog and replace the boiler? I am looking for advice on what to do, as it is making my head spin trying to work out the right thing to do. Help please! Thanks

windup

open up the valves, bleed them, and whack the thermostat up

If they are really gunged up, close both valves, put cloths down and remove/drain radiators one by one (open bleed to drain), and get to work with a hosepipe.

dharm999

windup wrote: »

open up the valves, bleed them, and whack the thermostat up

Done that, no air is trapped in them, wafrmish water comes out straight away. Thermostat is broken, forgot to mention that, so have no idea what temperature it is set to! Another thing to get fixed! Most of the radiators have old trvs on them to set their temperature, but I am assuming they are ok, as the radiators get warm at the top, and stay cool/cold at the bottom. We had radiators in our old house with trvs, and when they jammed the whole radiator was cold.

windup

unscrew the heads off the top of the trv, and check to see if the valve stem moves, cold radiators can be caused by the trv, try heating without the heads on. Similarly, if the lockshield on the other side is closed too much, it could also cause a similar effect.

Faulty thermostat could have some effect depending which one, where, what it's doing

dharm999

windup wrote: »

unscrew the heads off the trv, and check to see if the valve stem moves, cold radiators can be caused by the trv.

will try that tomorrow

Faulty thermostat could have some effect depending which one, where, what it's doing

There is one room thermostat on an internal wall that appears not to work. It doesn't 'click' when turned, unlike our old house where when you turned the room thermostat and it clicked you could hear the boiler coming on/going off.

Hintza

With three bathrooms I would be tempted to have a decent electric shower in one so that you have options for the day the system breaks down.

trailingspouse

You need to go with the best system you can afford. And you don't have to do it today.

When I moved in to this house, I knew I would be replacing all the radiators. I had the bright idea (one very hot summer's day) that as I would be replacing them all anyway, and as having them removed would make decorating easier, I would have them all taken out, then replace them one at a time as each room was renovated.

It wasn't a bad idea - except it took longer to get some rooms finished than we expected, so hot summer days turned into chilly autumn evenings, which turned into ****ing freezing winter nights. But - we survived it. We had a couple of gas fires downstairs, and an electric heater that we could move from room to room. And jumpers.

My point is - take your time over making this decision. Whatever you do will be expensive, so you need to be sure you're getting it right. If I was you, I would change to a combi boiler now (there are different sizes, so go for one that will work for your size of house), and get rid of all the tanks and so on. Then bit by bit as you work your way through the house (I'm assuming you're going to be decorating throughout over time) change the radiator in each room as required. In the meantime get a local plumber to come and see what he can do with the existing radiators, to squeeze a bit more heat out of them.

Seronera

Trailingspouse has said most of it for me. First get what you've got going as well as it can. Microbore is the spawn of the devil to clean out, so long term it will probably have to go. In the meantime you could get some system cleaner from Fernox or Sentinel (I use Sentinel X400) and get that into the system and follow the instructions on the bottle. You can't do any harm with it as its non acidic. It costs about £20 a bottle and then drain and refill and repeat to get loads of muck out of the system.

Only go to British Gas if you like paying a lot. They will do an OK job, but a combi sounds a bit of a daft suggestion to me in a sizeable house. Start saving and ask for some reputable local heating engineers at your nearest plumbers merchants. You will get a good job done to a higher spec for the same money, take it from me.

Get non working roomstat replaced (simple ones are dirt cheap). Make sure all the TRVs work by taking the heads off and 'easing' the valves with gentle pressure from 'an implement'...not a hammer!!!

Just keep doing the simple obvious and lowish cost sort of stuff, until you have a firmer idea of what you want to do. If you want to go really mad take off the radiators one by one and flush them through with a hose pipe in the garden..its usually a two person job as you have to swing the rad back and forth 'swooshing' the water inside. You get very black and dirty, but its very satisfying seeing all the gunk pour out. You'd be amazed how much there is. Good luck with the next 20 years