My uponor underfloor heating does not seem to be heating the hallway. Actuator is responding to commands ok and I set the stat high and have left it for 2 days to see if it heats the slab. So far I have nothing. Any ideas of things I can check?
UFH issues
- Thread starter zooankski
- Start date
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The hall way has worked previously. We have only been moved in a month and i am still getting my head around the system.
There are no flow indicators although i am guessing these could be retrofitted to the return manifold?
It is very hard to tell if there is flow by feel of pipe temperature as it is warm in there so an airlock might be the best guess in that loop?
Do the valves operate the same way as a radiator? i removed one actuator to take a look and guess they are just a pin valve. I have noticed today that half of the kitchen floor is still warm even though the stat is not calling for heat after a day.
I am thinking perhaps there is some debris in the system holding that valve open?
The system has obviously never been maintained by the previous owners as i found the mix actuator almost hanging off and orientated incorrectly (Uponor tech helped me over the phone with that as i thought mix temp looked high on controller)
Does anyone have any handy tips for a flush of the system and is it within the capability of an aircraft engineer lol
Thanks for the help so far!
There are no flow indicators although i am guessing these could be retrofitted to the return manifold?
It is very hard to tell if there is flow by feel of pipe temperature as it is warm in there so an airlock might be the best guess in that loop?
Do the valves operate the same way as a radiator? i removed one actuator to take a look and guess they are just a pin valve. I have noticed today that half of the kitchen floor is still warm even though the stat is not calling for heat after a day.
I am thinking perhaps there is some debris in the system holding that valve open?
The system has obviously never been maintained by the previous owners as i found the mix actuator almost hanging off and orientated incorrectly (Uponor tech helped me over the phone with that as i thought mix temp looked high on controller)
Does anyone have any handy tips for a flush of the system and is it within the capability of an aircraft engineer lol
Thanks for the help so far!
To purge one loop; turn off the main F&R & all loops, connect a garden hose to one of the manifold drain valves & a 'drain' hose to the other. Open up the drain valves & the one loop you want to purge, blast cold mains water through the loop until it runs completely free of air or shyte. Close drain valves, open all loop valves & fire up system........Job done!!!
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When you say turn all the loops off, do you mean using the stats? The drain valve are located at the end of the manifold I assume? I did find a small brass adapter to take a hose in one of the cupboard so I guess I screw it in there? What is the purpose of the brass hex head bolt over each return manifold loop? Also am I right in thinking that the aerated section under each actuator is used to adjust flow and balance the sustem? Thanks!
I found some instructions as this type of manifold is discontinued, however i am confused where it says to close all underfloor heating loop flow and return valves. I assume i just remove the actuators from the flow manifold to close those but am unsure about the return manifold. Does it mean closing the balancing lockshield valve on all loops which i assume is under the hex heads on the return manifold?. That would mean i need to write down how many turns on each to reset them?
Would i have an issue in just removing all the actuators and not shutting all the balance valves, connecting the hoses and the depressing the pin on the loop i want to purge??? ( i think this is what PullerGas is saying to do basically?)
For future reference, how hard would it be to have the manifold replaced with an up to date version and still use the same controls?
• Ensure all electrical supplies are switched off. • Remove the fill port cap and washer and connect the hose unions to both end caps. • The integral valves in both end caps must be opened to fill the system; remove the valve cap and washer and use a 4mm Allen key to open the valves. • Ensure the 1” BSP manifold flow and return valves on the manifold are CLOSED. • Close all underfloor heating loop flow and return valves on the manifold. • Fit a hose to the lower manifold hose union and run the other end of the hose to a suitable drain point. • Connect a hose to the upper manifold hose union and connect the other end of the hose to a mains water tap. • Individual loops need to be purged of air in turn. This is achieved filling the system one loop at a time by opening ONE pair of valves on the manifold, i.e. the first pair of manifold valves. • Turn on the water tap. As the first loop fills with water, air will discharge through the hose to the drain. Once the air stops and there is a steady flow of water, shut the loop flow and return valves • Repeat this procedure for all UFH loops on the manifold ensuring that the valves are closed on each loop after filling. • Close the valves on the end caps and switch-off the mains water before disconnecting the hoses. • If the UFH is being installed in the winter, anti-freeze can be added to the system water for protection against freezing.
Would i have an issue in just removing all the actuators and not shutting all the balance valves, connecting the hoses and the depressing the pin on the loop i want to purge??? ( i think this is what PullerGas is saying to do basically?)
For future reference, how hard would it be to have the manifold replaced with an up to date version and still use the same controls?
• Ensure all electrical supplies are switched off. • Remove the fill port cap and washer and connect the hose unions to both end caps. • The integral valves in both end caps must be opened to fill the system; remove the valve cap and washer and use a 4mm Allen key to open the valves. • Ensure the 1” BSP manifold flow and return valves on the manifold are CLOSED. • Close all underfloor heating loop flow and return valves on the manifold. • Fit a hose to the lower manifold hose union and run the other end of the hose to a suitable drain point. • Connect a hose to the upper manifold hose union and connect the other end of the hose to a mains water tap. • Individual loops need to be purged of air in turn. This is achieved filling the system one loop at a time by opening ONE pair of valves on the manifold, i.e. the first pair of manifold valves. • Turn on the water tap. As the first loop fills with water, air will discharge through the hose to the drain. Once the air stops and there is a steady flow of water, shut the loop flow and return valves • Repeat this procedure for all UFH loops on the manifold ensuring that the valves are closed on each loop after filling. • Close the valves on the end caps and switch-off the mains water before disconnecting the hoses. • If the UFH is being installed in the winter, anti-freeze can be added to the system water for protection against freezing.
I sussed out the problem with the UFH. 2 zone valves were crossed over so increasing demand for heat in the hall was simply heating the kitchen!
Flushing was actually pretty easy and I did get a little bit of debris out which must have been in there since new.
I am sure that either the original installer had no clue or the previous owners played with it as this was a simple mistake.
The mixer valve being the wrong way around was a bit harder to spot but that is another story!
I am having the manifold replaced next week with an Uponor TM version which will give me the benefit of ease of balancing and also get rid of a leak I found (very small hair line crack in one of the current balancing ports).
I have spoken to Uponor who recommended this manifold to me. They have said to heat the pipes with a hair dryer before removing the olives from the pex pipe. Am I right in thinking this is to prevent damage? I did read that pex will return to original shape after heating?
Obviously I am a bit worried about the swap and I don't think I can afford to lose any length of pipe due to it only being 25cm from floor level already on the return fittings.
New connections do not use an olive. Connections have been redesigned and incorporate it in them which is clever.
Any tips for removal of old olives to avoid damage would be greatly received and I can pass them on to the heating and plumbing engineer next week
Flushing was actually pretty easy and I did get a little bit of debris out which must have been in there since new.
I am sure that either the original installer had no clue or the previous owners played with it as this was a simple mistake.
The mixer valve being the wrong way around was a bit harder to spot but that is another story!
I am having the manifold replaced next week with an Uponor TM version which will give me the benefit of ease of balancing and also get rid of a leak I found (very small hair line crack in one of the current balancing ports).
I have spoken to Uponor who recommended this manifold to me. They have said to heat the pipes with a hair dryer before removing the olives from the pex pipe. Am I right in thinking this is to prevent damage? I did read that pex will return to original shape after heating?
Obviously I am a bit worried about the swap and I don't think I can afford to lose any length of pipe due to it only being 25cm from floor level already on the return fittings.
New connections do not use an olive. Connections have been redesigned and incorporate it in them which is clever.
Any tips for removal of old olives to avoid damage would be greatly received and I can pass them on to the heating and plumbing engineer next week
The ring is split at an angle and made from brass. Calling it "compression" in the usual sense doesn't apply here as it doesn't do any sealing.
If required for the change over you would slide the split ring back then remove the brass insert which will have O rings fitted.
The TM version might match your old bracket spacing's then it should be a straight swap.
16 x 2mm euro cone fittings and your old ones look the same.
Make loop connections with ¾” male-threaded Eurocone in accordance with DIN V 3838 compatible with Uponor MLC & PEX pipe adaptors.
Made of plated brass 3/4” FT Eurocone thread for connection to 3/4” MT outlets of NV/LS/TM manifolds.
NV = No Valves
LS = Lock Shield
TM = Top Meters
Once you know your outlet temperature from the blending valve its not that difficult to adjust the lock shield on an LS manifold to achieve a degree accurate temperature drop on each loop.
Each room in turn can have a different average mean temperature in the loops to cater for different floor types and heat losses for that particular room.
If required for the change over you would slide the split ring back then remove the brass insert which will have O rings fitted.
The TM version might match your old bracket spacing's then it should be a straight swap.
16 x 2mm euro cone fittings and your old ones look the same.
Make loop connections with ¾” male-threaded Eurocone in accordance with DIN V 3838 compatible with Uponor MLC & PEX pipe adaptors.
Made of plated brass 3/4” FT Eurocone thread for connection to 3/4” MT outlets of NV/LS/TM manifolds.
NV = No Valves
LS = Lock Shield
TM = Top Meters
Once you know your outlet temperature from the blending valve its not that difficult to adjust the lock shield on an LS manifold to achieve a degree accurate temperature drop on each loop.
Each room in turn can have a different average mean temperature in the loops to cater for different floor types and heat losses for that particular room.
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Cheers for the info Roger. I will let you know how it goes!
Manifold spacing is near spot on and only the feeds to it will need adjustment
Manifold spacing is near spot on and only the feeds to it will need adjustment
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