FORE Â Â 12 #37 Posted December 3, 2012 Hi, just had a new boiler fitted 24kw, to replace old one (10.5kw). The CH radiator water temp is set to an 'e' on the setting dial which is apparently the most economical temp. However the water for the rads is a bit hot and seems to give a lot of 'overshoot' in room temp. (Wall stat switches off but there is still the hot water in rads chucking heat out). Â It appears from reading I could do with a wall stat with 'heat Anticipator'. Which do you recommend please? My old one is wired & I could use these wires & site. Share this post Link to post Share on other sites Share this content via...
Complete-Heat   10 #38 Posted December 4, 2012 Hi, just had a new boiler fitted 24kw, to replace old one (10.5kw). The CH radiator water temp is set to an 'e' on the setting dial which is apparently the most economical temp. However the water for the rads is a bit hot and seems to give a lot of 'overshoot' in room temp. (Wall stat switches off but there is still the hot water in rads chucking heat out).  It appears from reading I could do with a wall stat with 'heat Anticipator'. Which do you recommend please? My old one is wired & I could use these wires & site.  This one from Honeywell will do the job. You can use the wires but needs to be 3 wire to feed the heat anticipator. Nearly all are a fairly straightforward swop over,  http://www.plumbworld.co.uk/honeywell-t6360b-spdt-room-761-1361?utm_source=GoogleBase&utm_medium=GB&utm_campaign=GoogleBase&gclid=CJuD3YnzgbQCFanItAod9G0ASg Share this post Link to post Share on other sites Share this content via...
FORE   12 #39 Posted December 5, 2012 (edited) This one from Honeywell will do the job. You can use the wires but needs to be 3 wire to feed the heat anticipator. Nearly all are a fairly straightforward swop over, http://www.plumbworld.co.uk/honeywell-t6360b-spdt-room-761-1361?utm_source=GoogleBase&utm_medium=GB&utm_campaign=GoogleBase&gclid=CJuD3YnzgbQCFanItAod9G0ASg  I called in plumbworld yesterday, they didn't know what i was on about. Think I saw the one you suggest, but couldn't see heat anticipator mentioned. See it has one from your link.  My ancient Honeywell one has 3 wires all live when fused spur is switched on.  THANKS! Edited December 5, 2012 by FORE Extra info. Share this post Link to post Share on other sites Share this content via...
Complete-Heat   10 #40 Posted December 5, 2012 I called in plumbworld yesterday, they didn't know what i was on about. Think I saw the one you suggest, but couldn't see heat anticipator mentioned. See it has one from your link. My ancient Honeywell one has 3 wires all live when fused spur is switched on.  THANKS!  its the one you need. you have live, switched live, and neutral. Its just a straight swop over (isolated at the mains of course). all modern thermostats have heat anticipator built in.  andy  ---------- Post added 05-12-2012 at 20:21 ----------  or you could install the Honeywell DT90E. a little more expensive as its digital but has the anticipator built in.  2 wire install so you would isolate the live and run the common / switched live and neutral from it.  andy Share this post Link to post Share on other sites Share this content via...
FORE   12 #41 Posted December 5, 2012 its the one you need. you have live, switched live, and neutral. Its just a straight swop over (isolated at the mains of course). all modern thermostats have heat anticipator built in. andy  ---------- Post added 05-12-2012 at 20:21 ----------  or you could install the Honeywell DT90E. a little more expensive as its digital but has the anticipator built in.  2 wire install so you would isolate the live and run the common / switched live and neutral from it.  andy Thanks for your time Andy. Are these anticipators variable for sensitivity? the ones I was reading about on the 'net had a lever setting or similar inside. Share this post Link to post Share on other sites Share this content via...
Complete-Heat   10 #42 Posted December 5, 2012 Thanks for your time Andy. Are these anticipators variable for sensitivity? the ones I was reading about on the 'net had a lever setting or similar inside.  Yes that's right. Dial ones have bimetallic strip that warms up quickly and so is more sensitive to temp changes. Newer digital Honeywell one has a resistor to compensate for the temp change. Even more sensitive which is why you can also put them Ito Eco mode.  Andy Share this post Link to post Share on other sites Share this content via...
FORE   12 #43 Posted December 5, 2012 Yes that's right. Dial ones have bimetallic strip that warms up quickly and so is more sensitive to temp changes. Newer digital Honeywell one has a resistor to compensate for the temp change. Even more sensitive which is why you can also put them Ito Eco mode. Andy  So with my problem, I would be better to have a digital one - and not just for the looks?  It appears my room temp was more steady with the old 10kw boiler as it was probably working most of the time to achieve a decent temp:) Not bad for a gas valve & relay, only repairs in 25+ years!! Share this post Link to post Share on other sites Share this content via...
Complete-Heat   10 #44 Posted December 6, 2012 So with my problem, I would be better to have a digital one - and not just for the looks? It appears my room temp was more steady with the old 10kw boiler as it was probably working most of the time to achieve a decent temp:) Not bad for a gas valve & relay, only repairs in 25+ years!!  Either will do as difference is so small. Suppose digital ones look smarter. Yes your old boiler would have been "cycling" to maintain the temp so using more gas. However as u said I have swooped over many,many old solid and reliable boilers. But reliable not efficient. Today there are not many reliable and efficient combos which is why us guys on here promote the best boilers to install.  Andy Share this post Link to post Share on other sites Share this content via...
Lucy-Lastic   10 #45 Posted December 12, 2012 (edited) Hi We have a Vaillant Ecotec Plus 831 that is just under 2y old and has started to fail and show a F.75 fault on really cold mornings. It does begrudgingly relight (at the moment) and the pressure is good. What could be causing this? What should I do about it - my installer suggested that I should just contact Vaillant... Edited December 12, 2012 by Lucy-Lastic Share this post Link to post Share on other sites Share this content via...
Complete-Heat   10 #46 Posted December 12, 2012 Hi We have a Vaillant Ecotec Pro 831 that is just under 2y old and has started to fail and show a F.75 fault on really cold mornings. It does begrudgingly relight (at the moment) and the pressure is good. What could be causing this? What should I do about it - my installer suggested that I should just contact Vaillant...  LOL.....installers fitting boilers that they know nothing about....bang a boiler in and walk away..  Vaillant are a fantastic boiler and were the only boiler make I used to fit. However, there is one boiler that is not as reliable as the rest....and yes its the "pro".. There is a problem with the pump used in that boiler as to save cost Vaillant used another supplier rather than sticking with Grundfoss. So the pump is the weak part and that's the problem with yours.  When it starts the firing sequence the control board monitors the pump speed. The seals in this pump can stick especially in cold weather and it struggles to start up spinning (so sends the code F75)  This code can also appear if the water pressure drops although the control board is so sensitive it will throw the code F22.  The pump needs replacing and now Vaillant have gone back to grundfoss so any replacement will give more years of fault free service  Andy Share this post Link to post Share on other sites Share this content via...
Lucy-Lastic   10 #47 Posted December 12, 2012 LOL.....installers fitting boilers that they know nothing about....bang a boiler in and walk away.. Vaillant are a fantastic boiler and were the only boiler make I used to fit. However, there is one boiler that is not as reliable as the rest....and yes its the "pro".. There is a problem with the pump used in that boiler as to save cost Vaillant used another supplier rather than sticking with Grundfoss. So the pump is the weak part and that's the problem with yours.  When it starts the firing sequence the control board monitors the pump speed. The seals in this pump can stick especially in cold weather and it struggles to start up spinning (so sends the code F75)  This code can also appear if the water pressure drops although the control board is so sensitive it will throw the code F22.  The pump needs replacing and now Vaillant have gone back to grundfoss so any replacement will give more years of fault free service  Andy  I realised it was a plus not a pro so is it still most likely to be a pump thing. It has been going ok since I kick started it again at 6pm. So do you also suggest that I call Vaillant direct? Share this post Link to post Share on other sites Share this content via...
Complete-Heat   10 #48 Posted December 12, 2012 Vaillant give a standard guarantee on parts and labour for 2 years. But the boiler must have been installed by an installer who is gas safe registered and who notified the boiler. So yes call them to repair.  They will also make sure that the installer properly flushed the heating pipework. The reason I say this is I think your pump is sticking on your "plus" model (which is a grundfoss pump) due to sludge. Again in cold weather it gets thick and the pump struggles to spin. If you have a magnetic filter on (magnaclean), Vaillant will swop the pump over free of charge no questions asked. Share this post Link to post Share on other sites Share this content via...