Search results

thanks @jeff the gasman. The boiler is currently set to a maximum heat output of 20kW (by setting d.00 on the boiler to 20). Even with this setting, the boiler is continuously cycling when only the UFH is on. If the boiler is 'down rated' any further, will this not be insufficient to cater for...

Apologies if this has already been answered before but I recently had installed a wet Underfloor Heating (UFH) system to a newly built orangery 6m x 4m). The rest of the house is a wet central heating (CH) system containing 21 radiators. I have a Vaillant ecoTec Plus 438 condensing boiler...

@Johntheo5 - photo attached showing pipes from expansion vessel

Thanks @Johntheo5. I will try to answer some of your queries on the attached tomorrow where I can. My boiler is covered by British Gas and they carried out an annual service on 26/9/22 which included cleaning out the magnacleen. From the attached, I’m 99% certain that the boiler flow pipe is...

@Johntheo5 - I have attached some photos. - 2 photos showing the boiler in the garage and the expansion vessel gauge - hot water zone valve (labelled in yellow with the number 1). Within this photo, the 2 white pipes at the front are coming from the UFH manaifold - zones valves - the one...

thanks @Johntheo5 but before I turned on the UFH, the boiler was not cycling through S2 --> S4 --> S7, and the boiler happily stayed at S4. Has, by turning on the UFH, caused some poor circulation within the Grundfos pump/CH system? I am now really baffled :(. I have now turned off the CH...

thanks @Johntheo5. I now have just the CH running but the boiler is continuing to cycle from S2 --> S4 --> S7 at 7kw When the boiler shows S4, d.40 rapidly goes up to 67 before S7 kicks in. d.41 stays at 37 What has changed? Before when only the CH was ON, the boiler was staying at s.4 and...

@Johntheo5 - I have turned off the UFH as I am concerned I might be causing damage to it. The UFH pump is on but is cold too. I have attached some photos of the UFH while the UFH system was on

@Johntheo5 - the zone valve for the UFH is open so don't understand why the UFH is not turning on unless when the engineer power flushed the boiler pipes, this has an effect

So after about 15 mins with both CH and UFH on, I have been by the boiler and it keeps going from S.2 to S.4 to S.7 which is not what it was doing before when just the CH was on. D.40 rapidly climbs to 68 when the boiler is firing and d.41 is 38 when S.7 kicks in and the boiler stops. Both...

Ok @Johntheo5. Stupid question but where to I take the readings from for the UFH flow rates?

oh, @Johntheo5, I turned everything off as the house was getting too hot . Shall I turn back on the heating with d.00 at 7kW and then also turn on the UFH? Do you want me to note down d40 & d.41 after a period of time?

@Johntheo5 - the minimum I can knock it back to is 7kw. After 10 mins, readings were d.40 = 62, d.41 = 45 Attached are some photos of the labels shown on the boiler; one of them shows that it is a Vaillant ecoTEC plus 438 along with its serial number. The furthest rads are still struggling to...

@Johntheo5 - I've knocked back d.00 to 10kw and after: 10 mins, d.40 = 63-65, d.41 = 45 20 mins, d.40 = 63-65, d.41 = 45 30 mins, d.40 = 63-64, d.41 = 45 UPS speed is on III, and boiler is continuing to show s.4 The fact that d.40 is not getting ~ 60C, what indication is this giving?

after 25 mins, d.40 = 63, d.41 = 40. Boiler still showing s.4 Nearby rads are getting warmer

thanks @Johntheo5. I carried out the above steps. After about 10 mins, d.40 is 57, s.41 is 33 Boiler is showing s.04 but is firing at low output. Nearby rads are luke warm, rads further away are cold

thanks @Johntheo5 but I only have the one Grundfos pump that is located in the landing cupboard by the zone valves so to manually change the pump speed depending on whether I have the rad system running or the UFH running will be impossible, unless I have misunderstood your point? I have had a...

thanks @Johntheo5. Unfortunately, by the time I remembered to check the d.40 & d.41 temps, the heating had already been running for 30 mins from cold this morning. I guess I will need to wait until later in the day when the rads heating starts again to immediately check what d.40 & d.41 are...

ok @Johntheo5. Sorry if you have already mentioned this but what do I need to do to reduce the boiler dT to below 30C? Is it to sort out the current problem that I'm having with the rad system? What can I do to increase the UFH demand to prevent boiler cycling? If there is an issue with my...

thanks @Johntheo5. Is the TMV the blending valve on the UFH manifold? If so, this is set at 45C. From the info you shared, is there anything I need to do with the settings on the UFH or am I likely to experience issues with the UFH I have based on how things are currently set up?