pacemaker1000

Had two red herrings.🙄 bulb gone in 'heat demand' tested with metre and ok. temperature sensor in wrong place. Was on 2nd manifold tee meaning only way it got heat was conductive and not flow. adjusted and boiler now comes on at 40 and off at 45

I have two manifolds on two floors. Second floor is working perfectly, room stat calls for heat, actuators open, pump comes on and demand light comes on and calls for heat from the boiler. ground floor has suddenly stoped demanding heat? stats on, actuators open and pump comes on but demand light doesn’t come on and boiler won’t start? thanks

Both open just a quarter turn

I do have them but turned them off as temperature already controlled by blending valve doesn’t make sense to cool down the controlled temperature with cold water 🤷🏼‍♂️

So you saying 30-35 is the flow temp? any thoughts on the manifold mixers? Why would you use them if the flow temperature is already set correctly?

Cheers guys especially for the PDF diagram. This is exactly my setup! I do have two manifolds and both are in concrete so same temperatures. any ideas on settings for 'room temp' and 'limit' I thought the ideal temp was about 40 degrees so expected to see a dial to select that not room temp set to 25 degrees as that is the desired room temp controlled by individual stats in the rooms? also don’t see point in mixing valve on each manifold when both require the same temp from the boiler? if the flow is sending 40 degrees to each zone why would you want to cool that down with the return cool water?? cheers

This was in house on purchase. so does it work as I described? why would I need a gate valve or any valve on the manifold given the setup! looks like in theory setup is correct just that it’s at the boiler not the manifold to save having to do it twice for second floor. valves on manifold were a mistake control panel set to room temp of 25 which is about right also max of 40 makes sense for UFH?

Ok it’s starting to make sense I think 🤔 back at the boiler there is a 4 way controller I assume is for temperature control see pic. It has five settings and is currently on '0' It connects to boiler flow, manifold pump, manifold return and boiler return there is also a temperature sensor zippa tied to the manifold flow. see pic of temperature control panel and please advise on setting. All my underfloor is in concrete! with this in mind my thought is the original post and pic of control valves on actual manifold , this is redundant and should be fully closed as it interferes with the 'proper' temperature control near boiler as it effectively cools the set temperature in the flow? I assume it’s located there as I have two manifolds , second one upstairs, and this is able to control both? would be nice to have a physical temperature gauge to check it is does g what it should. Maybe a clip on one somewhere thanks

Hi guys, yes it’s a mixer valve no a stopcock sorry. Wrote that to better describe its physical appearance as can be seen in the new pic. pump is back by boiler not near manifold and as you can see no temperature or pressure gauges. So no way to know where to set the mixer.?

Sorry no pic yet but my manifold has no temperature gauges and only a manual stopcock between flow and return. so how do I know how to adjust the stopcock so the cooler return water ensures the correct temperature in the flow? considering a clip on thermometer and turning stopcock until it’s around 40 degrees? setting boiler at 40 degrees and turning stopcock off? thanks

Those of us on oil have paid a heavy price for ever. the thought of it now being the cheapest is quite scary:

Worked out during winter I average 10 litres of oil a day which converts to between 80 and 90 kw a day. So using 3.5 cop that could be 22-25 kw I think? so that would at todays prices be £7 for ASHP compared to £10 for oil? at next month that gain would be lost if I’m right

Thanks guys. Few answers… house built 2005 efficiency is C 82 design from company if for 18kw ASHP to include DWH Direct replacement will mean hot water tank could be used and topped up with immersion by cheap rate or solar so not a priority. current UFH set at 35-40 I think so not high only 3 rads in house other 12 rooms UFH if on all day what would it cost once reached temperature? thanks

My current system is a standard oil boiler heating UFH and HW (300l tank). Although I currently use the immersion for HW with cheap electric and may also use solar. so boiler is currently off and will only be used in winter for heating only. Boiler flow and return only connection to boiler so can this just be swapped to an ASHP flow and return pipe work? probably a stupid suggestion but would appreciate comments

Sorry Hugh I don’t understand why you’d query getting the grant? ASHP cost is around 4-5k as don’t get vat back on direct purchase. Plus install would be at least £2k, so £7 in total? with grant it’s completely free or at most just the difference in a 10 and 12k pump….no brainer? re other comments: I would run hot water on whatever is the cheapest which would probably be Pump during cheap electric? During this time in winter I would take advantage of cheap electric to heat all rooms to about 22*C, or at least best it could do as concrete will then retain heat during most of the day and Pump would kick in when needed. So question would be whether Pump could cope with DHW and heating during this short period. of course in Summer HP is not needed if using alternative ways for the DHW. This would mean he ASHP would be turned off completely for 6 months and don’t know if this would be a bad thing so using it for hot water may be necessary?