Too many rads for my boiler ?

PrivateRyan

It's an extended 3 bed semi (sorry - my bad). The garage was converted before we bought and is now a dining room (1). Downstairs bathroom added (2). Conservatory now has a rad (3) and the bottom of the stairs was very cold so another rad there (4). That's 4 more than usual. Thing is, the heating was never "all that good" in this house - although we hoped it was fixed when plumber found a pipe that was totally blocked in the airing cupboard. Apparently, there wasn't enough water in the system because of this blocked pipe. Anyway - that was sorted several weeks ago, and since then - all the rads come to temp very quickly except for these last 3.

It's 15ml piping to the rads.

I guess by playing with the lockshields i've made things worse. Proper plumber can balance system correctly using temp gauges etc... right ? I am shocked however that i've not randomly landed on a good setup - i've been messing about for AGES with these lockshields. 8-(

keystone

PrivateRyan wrote: »

It's an extended 3 bed semi (sorry - my bad). The garage was converted before we bought and is now a dining room (1). Downstairs bathroom added (2). Conservatory now has a rad (3) and the bottom of the stairs was very cold so another rad there (4). That's 4 more than usual.

OK understand. Which is the one which is permanently cold and where is your Roomstat in relation to it?

Thing is, the heating was never "all that good" in this house - although we hoped it was fixed when plumber found a pipe that was totally blocked in the airing cupboard. Apparently, there wasn't enough water in the system because of this blocked pipe.

Blockage where the cold fee comes down from the F&E tank I'm guess. Absolutely classic, a primary suspect and so often overlooked when there's poor circulation.

Anyway - that was sorted several weeks ago, and since then - all the rads come to temp very quickly except for these last 3.

It's 15ml piping to the rads.

OK thanks. CH suggestion of upping the size on some of the runs prolly has some merit in the final analysis but we need to get past a few other things first.

I guess by playing with the lockshields i've made things worse.

IMHO yes but thats just my opinion.

Proper plumber can balance system correctly using temp gauges etc... right ?

Actually you can do it yourself. Its not that difficult.

I am shocked however that i've not randomly landed on a good setup

I'm not!

- i've been messing about for AGES with these lockshields. 8-(

mmm - yeah.

Now about the TRV - is the valve free and does it make a difference?

Questions about the pump please?

Wheres the roomstat in relation to the rad with the TRV?

Cheers

keystone

BTW putting a radiator in your conservatory has technically changed its status to extension. You might like - not now but sometime - to check where you stand in relation to planning. You have a converted garage and a conservatory which is now an extension. You may have exceeded permitted development allowances but that will probably only surface as a problem if you decide to sell.

Cheers

PrivateRyan

Loving all this info keystone - thanks. The garage into an extension was before we moved in, and was therefore covered in our purchase (it's older than 10 yrs anyway). Good point re: conservatory ....

OK - the TRV. I took it off the rad in the conservatory, and can press the plunger. It's only quite small (2mm?) and doesn't travel all that far. It does however move and comes back up instantly. I've left the TRV head off for a while, and no noticeable difference to the rad temp. It's room temp at best. The water at the leg is slightly warmer, but not hot by any means. All 3 rads that are now suffering are close together (downstairs kitchen, bathroom and conservatory). The conservatory is the latest addition and is a big rad. I never expected it to get roasting hot, we just wanted to take the chill out of the air.

I don't think i have a roomstat (queue laughter ?!?!). Our boiler has a dial on it, and we've always controlled the temp like that.

Is there a Q about the pump that i've not answered ? I can't see one.

keystone

PrivateRyan wrote: »

Loving all this info keystone - thanks. The garage into an extension was before we moved in, and was therefore covered in our purchase (it's older than 10 yrs anyway). Good point re: conservatory ....

Just something to bear in mind. Don't forget that the cumulative total for percentage increase by extension is related to the original property as built not what it was when you bought it! But thats by-the-by.

OK - the TRV. I took it off the rad in the conservatory, and can press the plunger. It's only quite small (2mm?) and doesn't travel all that far. It does however move and comes back up instantly. I've left the TRV head off for a while, and no noticeable difference to the rad temp. It's room temp at best. The water at the leg is slightly warmer, but not hot by any means. All 3 rads that are now suffering are close together (downstairs kitchen, bathroom and conservatory). The conservatory is the latest addition and is a big rad. I never expected it to get roasting hot, we just wanted to take the chill out of the air.

Thats helps so we don't have a sticky PRV but we do have a circulation problem to there. Lets check the circulating pump next - see later.

I don't think i have a roomstat (queue laughter ?!?!). Our boiler has a dial on it, and we've always controlled the temp like that.

Ok - I was concerned that the rad with the TRV might be right next to the Roomstat. If the TRV is set to position 2(say) but the room stat is set to 22 degrees the TRV closes when the temp is correct for it. The roomstat continues calling for heat because the temp doesn't get high enough because the TRV has shut the rad down so it doesn't provide the heat. What happens is that they fight one another and thats how that rad will never get warm! Anyway thats that one dealt with as a possibility.

Is there a Q about the pump that i've not answered ? I can't see one.

Yes. What speed was it set to before you changed it. What speed does it work on? Do the other settings work at all? Give it a chance to stop and restart which it does do when you change speed.

Sorry for slight delay in answering - I'm trying to get the HSL painted (primary task per EID this am) and only attending to the PC every now and again.

Cheers

DVardysShadow

OK, you tried shutting all the valves except on the 3 rads in question and they don't all come to full heat. I am developing a gut feeling that these 3 rads are not in parallel [2 pipe system] but may be run single pipe with the return pipework. Or you have a single pipe system and these 3 rads are plumbed in as 2 pipe off 1 radiator system.

Your pump should be adequate - the grundfos IIRC has 3 settings. The middle setting should be adequate, but you might as well use the highest until you get to the bottom of what is happening.

Now as for your boiler size, it does appear that you have 25% more radiators than boiler. That should not be an immediate problem if you have TRV's, because the TRV's will cut the demand down. You should only worry about your boiler size if after several hours of running it does not stop for 20 or 30 minutes on the trot.

As I say, I think you have a half hacked system. I suggest you do a little research on 1 pipe and 2 pipe systems and understand the difference and then you investigate your pipework and attempt to draw it out to see if this is the case. If it is, I don't think you will want to take on fixing it until the heating season is over - there will probabaly be some difficulty which led to a botch being made. I would suspect that the 3 rads are something to do with the extension.

keystone

DVardysShadow wrote: »

Your pump should be adequate - the grundfos IIRC has 3 settings. The middle setting should be adequate, but you might as well use the highest until you get to the bottom of what is happening.

Without wanting to appear to be rude you didn't read when he said earlier today that only 1 speed setting is working. I'm trying to establish if thats correct or not. It may be a circulator issue but we have not finally established that or not and TBH this part of your post doesn't help as a result. If you want to carry on with this and see it to a conclusion today thats fine and I won't be the slightest bit offended. I do have other things to do and I really wasn't aware that this was a competition.

Cheers

PrivateRyan

Right. As you say, the pump does infact work on the other settings. Judging by the sounds (and the marks that i can just make out if i get close to it), my pumps was on the 3rd setting all along. I've tried the other settings briefly and the noise output (along with the fact that it says I and II against the other positions) makes me think that the original setting was the highest.

Is there any point in me listening to the pump when the boiler has switched off (which it does every so often when it's on) ... don't suppose this will tell me anything ?!?

Happy to receive any advice from here. I think we've concluded that it's not the PRV - the boiler is perhaps under powered but shouldn't result in the problem i'm having (too this extent anyway). The pump is on the highest setting and my pipes are perhaps a little too thin in places.

Again, thanks for all the support.

DVardysShadow

keystone wrote: »

I really wasn't aware that this was a competition.

It's a team effort. If you feel I am cutting across you then sorry. But with a problem like this, the only person who is going to be master of it is the OP after he has fixed it. In the meantime, there is no one right approach and every good reason for as many ides as possible to go in the pot.

PrivateRyan

DVardy - this bit about single pipes etc...., how best can i tell ? Remember, i'm not one for taking up floorboards ... is there a way i could experiment with the settings of the rads to prove/disprove.

Keystone, is there anything else you think i should be checking ? Is it worth another attempt at all the rads lockshielded off and play on the 3 remaining rads ? Is this any different to simply turning them down using the other valve (my knowledge really shining through here !!).