Worcester Greenstar Ri Central Heating Problem

[epod184]

Hi,
Non-plumber seeking advice for Worcester Greenstar Ri boilerfitted aprox 2005.
We have hot water without a problem. But the heating is notworking effectively.
The boiler will fire up, and start heating a few of theclosest radiators, but never gets really hot and the distant radiators barelyget warm. The radiators do not need bleeding (I've done it).
A plumber has said something is not correctly wired up, so ho****er for the radiators is being used to go through the hot water tanks first,before going to the radiators. He said fixing that would help, but didn't thinkit would fully solve the problem. (possibly a switch valve?)
Another plumber recommended replacing the whole boiler witha pressurised system, at a cost of roughly £5k!
Both have said the boiler is possibly too small for the sizeof the house, we have a 4 bed Victorian semi-detached with small extension.Total 17 radiators.
From what I can see, the boiler doesn't stay on very long.The heating timer will start, and the boiler will fire. It will run for a bit,then maybe after 10 minutes it will shut off for a bit. Then after a fewminutes it will start up again, and do the same thing. Sometimes it stays onfor a few minutes, sometimes for 20 mins.
There are not flashing blue lights, and the green lightcomes on.
Any suggestions on what is wrong...... is the boiler bigenough for 17 rads..... will wiring up the switch valve likely to solve theproblem..... should the boiler be going on and off like it is?

Many thanks in advance.
Epod.

 

[ShaunCorbs]

what ri do you have ?

and sounds like either a blockage or pump is big enough, but if you installer a bigger pump you have a chance of it pumping over (pumping back into the f and e tank via the vent)

and shouldn't cost that much to convert depending what he priced for

 

[epod184]

Hi Shaun, thanks for quick reply.

It's Greenstar 24Ri.

The £5k quote was to replace the whole boiler and system with a pressurised one. So replacing two tanks in the loft, and installing a return pump. He also couldn't guarantee it would fix the problem.... so I wasn't prepared to fork out £5,000!
For me I think something is broken. If when the boiler was first installed it did not heat the radiators properly, surely the home owner then would have challenged the installer.

It's not worked properly since we have been in the property.

 

[ShaunCorbs]

right so its an open vented system
twin channel programmer with either a 3 port or two two ports ??

and just off my gut if both are on hot water and heating boiler is on the small side

 

[Gasmk1]

Pump could be on its way out

 

[ShaunCorbs]

not if its never worked/heated

 

[Unregistered]

Sorry, I don't know how many ports it has.... how do I find out?

I don't know if it has never worked, we have been here 2 years and it has always been the same. I just figured the people who had it installed first would not have accepted it if it never really worked from new... unless they did it themselves I guess.

Would having the switch valve wired up correctly solve the issue do you think? We wouldn't need to have hot water and heating on at the same time. Or if not, what would the best fix be..... a new boiler?

 

[ShaunCorbs]

will look like one of these

where are you located maybe one of our members are close to you?

 

[joni os]

Boiler cutting out before rads get hot indicates circulation problem. Cause:- Motorized valve, Pump or blockage in system. Cure by elimination.
Remove heads of motorized valve(s) with electrics in place and move spindle manually to heat position. Check pump by substitution, then with balancing valves fully open, but all rads closed bar one, ensure each rad in turn fully heats up. Any rad that fails to heat, provided TRV is not stuck, indicates blockage in system. If cause found to be blockage, flush in manner that protects boiler and add magnetic filter to system. Rebalance rads once circulation established.

 

[epod184]

Thanks both of you for your replys.

I'm guessing it's a 3 port, as it has three pipes connected...


So can I move the switch on it manually to select what it does? One of the plumbers said it wasn't wired up. The switch has 'W', 'M' and 'H' on it..... assuming 'W' is hot water, 'H' is heating and 'M' is... both? If I move it to 'H' and then turn off all the radiators except one, would that be the way to test like you are suggesting Joni os?

Shaun I am between Bristol and Bath..... hopefully someone is close by

 

[ShaunCorbs]

if its plumbed right yes turn it to manual heating and only heating should come on if you can feel it heating your hot water it needs replacing

and easy way to tell if its wired

manually operate it to either setting and pump should come on then boiler should fire

 

[joni os]

Can't identify 3 port valve but suspect lever on top is indicator and a different lever underneath manually controls valve.( like obsolete AOL). Goggle make of valve, might find head removal simple. Shaun is right that manual opening can trigger micro switch and fire boiler but sometimes wear in mechanism prevents this happening manually although contact will still be made when valve fully open by motor. All three pipes off valve will quickly become hot so when checking if DHW cylinder is isolated, feel lower pipe from coil coming out of cylinder.

 

[ShaunCorbs]

Can't identify 3 port valve but suspect lever on top is indicator and a different lever underneath manually controls valve.( like obsolete AOL). Goggle make of valve, might find head removal simple. Shaun is right that manual opening can trigger micro switch and fire boiler but sometimes wear in mechanism prevents this happening manually although contact will still be made when valve fully open by motor. All three pipes off valve will quickly become hot so when checking if DHW cylinder is isolated, feel lower pipe from coil coming out of cylinder.

looks like a drayton 3 port

 

[epod184]

Ok, so the thing on the right is an indicator. There is a push button on the left which doesn't seem to do anything. And a pull out lever on the top, which can only be pulled out when it's all off. when I pull it out it just goes lose.... doesn't seem to change anything. (sorry, can't seem to rotate the picture.... left and rights based on the text on the switch)



If I change the settings using the controller by the boiler, I can get it to go all the way to W when just hot water is on.... and when hot water & heating is on it goes to 'M', and with just heating on it stays on 'M'. It never goes to 'H'

 

[joni os]

Drayton head can be removed by pressing lever on base. ( Not the indicators shown on top). If mid position valve, manual opening in locked position leaves both heating and hot water ports open. This is why I prefer to remove head and move spindle to suit. With head removed it doesn't matter if the program is calling for heating or hot water, position of spindle decides outcome.(Provided room stat and cylinder stat both call for heat)

 

[joni os]

Ok, so the thing on the right is an indicator. There is a push button on the left which doesn't seem to do anything. And a pull out lever on the top, which can only be pulled out when it's all off. when I pull it out it just goes lose.... doesn't seem to change anything. (sorry, can't seem to rotate the picture.... left and rights based on the text on the switch
View attachment 25771

If I change the settings using the controller by the boiler, I can get it to go all the way to W when just hot water is on.... and when hot water & heating is on it goes to 'M', and with just heating on it stays on 'M'. It never goes to 'H'

Good your heating is not working because water is taking easy route through coil and not being forced around heating circuit. Get 3 port valve correctly wired.

 

[joni os]

Additional information. Using your orientation, ie as writing on valve:-
Turn off power. Depress button on left and at same time move lever at top end to locked position. Head will now lift away from valve. After this you can rotate spindle to heat only position, power back on and when boiler fires check rads as previous.

 

[epod184]

Ok, I removed the head and tried to manually move the spindle. It seems really stiff and difficult to move with a pair of plyers.

I assume if the spindle is dead straight, that is in neutral. With the plyers I can only really get it to turn 5 degrees anti-clockwise (towards heating). Should it be moving more than that?

Also the boiler never really stays on very long.... so the feed pipe into the switch never really got that hot, because it doesn't seem to stay on very long. Is that because the hot water is up to temperature so it shuts it off?

 

[epod184]

Additionally.... if I play with the room stat that seems to function correctly.

With the heating on through program, if I turn room stat down the switch will got to water. If I turn it back up it goes to the middle/marginally towards heating).

 

[joni os]

I find a small adjustable spanner on flat of spindle easier than pliers. normally flat will move through 180 degrees ie. facing heating pipework or facing pipework to DHW cylinder. If range of movement less than this internal malfunction of valve suspect. With manual lever on head in locked position check orientation of flat this will ensure you are moving spindle correctly.
Because valve has not gone to heat only for some time persuasion may be require to achieve full rotation, move spindle clockwise and anticlockwise but avoid brute force.

 

[epod184]

I used a small adjustable spanner and only with a small amount of persuasion the spindle has come off....
It doesn't look broken, as it has a very clean edge.... but as it's not going back on, I can only assume I have broken it
Given how locked up it was, I suspect a replacement was needed anyway. I think... and hope... it is stuck on the hot water position!

 

[joni os]

These things happen to all of us. With much force required, motor would not have moved valve. Only necessary to drain down to valve height. If there are rads higher than this then close trvs. Use identical M valve so nuts and olives will be compatible. Can fit old head to new valve. You won't be paying £5K for new boiler so may consider giving plumber a days work to wire correctly and get heating up and running. Good luck.
22mm pipework/22mm valve. 28mm pipework/28mm valve. Check pipe size before purchase new valve.

 

[ShaunCorbs]

as above and not suppose to be removable and maybe chuck some cleaner in also when he refills and then leave it week or two and drain and re fill with inb

 

[epod184]

Thanks guys. I think it's definitely worth me calling a plumber to replace the valve. By the sounds of it that was the problem... so hopefully with that replaced it should be all sorted.

I will ask the plumber to put some cleaner in while they are there.

Will update the thread once done, hopefully with it all sorted

Many thanks!