Help with Salus auto-balancing actuators

[Jeremy Harris]

23 minutes ago, europa said:

 I'm not sure how reliable the manifold thermometers are, but the temps they show are very erratic.

 

We have the same type of manifold thermometers and they are hopelessly inaccurate.  I tried to find more accurate ones that would fit the ports in the manifold but failed miserably.  My first solution was to buy some of these cheap digital thermometers and poke their sensors into the holes in the manifold: https://www.ebay.co.uk/itm/Mini-Digital-Fridge-Freezers-Coolers-Chillers-Aquarium-Thermometer-Probe-Sensor/333389376769?hash=item4d9f8e2d01%3Am%3AmCniJn-0tAsdFCUJGopbXZg&LH_BIN=1 but I found that these stick on LCD temperature indicating strips were easier to fit, although they are harder to read: https://www.ebay.co.uk/itm/Stick-On-Digital-Thermometer-Adhesive-Aquarium-Fish-Tank-Glass-Water-Window-LCD/182082101146?hash=item2a64f05f9a%3Ag%3AJ8oAAOSwuolboq37&LH_BIN=1

[Temp]

2 hours ago, JFDIY said:

The calibration notes advise to run an increased manifold temp for the calibration exercise, so that the actuators always see a rise. If the manifold temp is falling it will fool the actuator as the supply will be dropping but the return stay the same briefly and it's looking at the difference between the two.

Anyway, when starting the calibration I believe the actuator incrementally opens the valve until a temp rise is detected, then uses this as a base point for valve closure.

 

 

 

So perhaps manually forcing a recalibration one at a time with others off, rather than all at once might help?

[JFDIY]

I did no more than two at once and a couple individually, I turned the 'stats down on the zones I wasn't doing so they didn't draw heat from the manifold mid-way through calibration.

 

 

[europa]

Well, it's been like watching paint dry today, but, with just one loop left, i think it's safe to say i have finally succeeded! 

WF did send me a new batch of actuators (and it's those that ive been using), but i don't think its that that's made the difference. I think the key is simply patience! But, for anyone who's interested, here's the procedure ive used:

1.Switch off flow to all loops. Then, attach and calibrate one actuator at a time, as below. 

2. Attach the temp probes onto flow and return pipes 10cm from the manifold (as per instructions) and screw on actuators finger tight. 

3. Power up actuators and the LED should then rapidly flash at ca. 4Hz (not 0.25Hz as stated in the instructions). 

4. After just under two minutes, the LED will change to a slow blink and the actuator motor can be heard moving its pin to open the valve if its not already open. 

5. After a short pause, the actuator motor will reverse to fully close the valve. 

6. This is where the patience comes in.  Next it opens the valve at tiny increments (not perceivable) to find the point of min flow in the flow pipe. This can easily take another 20+ mins, and its easy to think that the actuator is stuck, but don't give up! Eventually, the actuator will kick back into life and, with a slow flashing LED, reopen the valve fully.

7. Shortly after this it will move to stable operation and calibration will be complete. You can then switch off the actuator and it should close the valve fully. 

8. To be on the safe side, i waited 40+ mins before switching off. 

 

Hope this helps others. 

 

Edited February 2, 2020 by europa
.

[europa]

Just a quick update. I was successful with all new (uncalibrated) actuators using the above procedure. However, i have so far been unable to recalibrate a previously-calibrated actuator. The reason i know this (and the easiest way to tell its in calibration mode) is that after the initial charging, open and close valve procedure (complete in just under 4mins from power on), there should be a long period of the actuator doing nothing - c. f. point 6 above. If, instead, the actuator reopens the valve fairly quickly (as is the case for me when trying to recalibrate), it is not in calibration mode. 

Clearly the instructions for recalibration are innacurate. I will have to call Salus again to find out if there is any other way to force the actuator to forget the original calibration. But if anyone has any ideas (or has successfully recalibrated one of these), do please let me know. 

[Temp]

17 hours ago, europa said:

4Hz (not 0.25Hz as stated in the instructions). 

 

I note that a period of 0.25 seconds is 4Hz so that's probably where the error comes from.

[OldSpot]

On 02/02/2020 at 18:31, europa said:

Well, it's been like watching paint dry today, but, with just one loop left, i think it's safe to say i have finally succeeded! 

WF did send me a new batch of actuators (and it's those that ive been using), but i don't think its that that's made the difference. I think the key is simply patience! But, for anyone who's interested, here's the procedure ive used:

1.Switch off flow to all loops. Then, attach and calibrate one actuator at a time, as below. 

2. Attach the temp probes onto flow and return pipes 10cm from the manifold (as per instructions) and screw on actuators finger tight. 

3. Power up actuators and the LED should then rapidly flash at ca. 4Hz (not 0.25Hz as stated in the instructions). 

4. After just under two minutes, the LED will change to a slow blink and the actuator motor can be heard moving its pin to open the valve if its not already open. 

5. After a short pause, the actuator motor will reverse to fully close the valve. 

6. This is where the patience comes in.  Next it opens the valve at tiny increments (not perceivable) to find the point of min flow in the flow pipe. This can easily take another 20+ mins, and its easy to think that the actuator is stuck, but don't give up! Eventually, the actuator will kick back into life and, with a slow flashing LED, reopen the valve fully.

7. Shortly after this it will move to stable operation and calibration will be complete. You can then switch off the actuator and it should close the valve fully. 

8. To be on the safe side, i waited 40+ mins before switching off. 

 

Hope this helps others. 

 

Just wondering if you disconnected (electrically/mechanically) the calibrated actuator before then calibrating the next?

[Fly100]

I have 12 on my system and one appears to have gone faulty. Ive recalibrated them all on that zone but one remains operating with a mind of its own. It wont close fully, so when that zone is off there is still hot water flow. The pin inside the actuator does not appear to move far enough to close the flow.

Ive emailed Salus last week, no reply as yet.

[Tony Rae]

On 02/02/2020 at 18:31, europa said:

Well, it's been like watching paint dry today, but, with just one loop left, i think it's safe to say i have finally succeeded! 

WF did send me a new batch of actuators (and it's those that ive been using), but i don't think its that that's made the difference. I think the key is simply patience! But, for anyone who's interested, here's the procedure ive used:

1.Switch off flow to all loops. Then, attach and calibrate one actuator at a time, as below. 

2. Attach the temp probes onto flow and return pipes 10cm from the manifold (as per instructions) and screw on actuators finger tight. 

3. Power up actuators and the LED should then rapidly flash at ca. 4Hz (not 0.25Hz as stated in the instructions). 

4. After just under two minutes, the LED will change to a slow blink and the actuator motor can be heard moving its pin to open the valve if its not already open. 

5. After a short pause, the actuator motor will reverse to fully close the valve. 

6. This is where the patience comes in.  Next it opens the valve at tiny increments (not perceivable) to find the point of min flow in the flow pipe. This can easily take another 20+ mins, and its easy to think that the actuator is stuck, but don't give up! Eventually, the actuator will kick back into life and, with a slow flashing LED, reopen the valve fully.

7. Shortly after this it will move to stable operation and calibration will be complete. You can then switch off the actuator and it should close the valve fully. 

8. To be on the safe side, i waited 40+ mins before switching off. 

 

Hope this helps others. 

 

Hi there,

 

I only joined this forum to say thank you to the above member (@Europa) for the walk through!

 

I had been having real trouble trying to get my Wunda underfloor system with Salus ABA's to work. Having read through the above and a couple of other posts, I noted three main things which helped me get the issues sorted:

 

1. The instructions are wrong (as Europa points out) and the LED's flash rapidly for the first 2 mins in calibration mode

2. You need to do the valves one at a time instead of doing all of them (5 in my case) at once

3. You need to be v patient (which I was not) and not just give up when they initially open and close again within a minute or so

 

I rigged up a simple light switch on the live lead of each actuator and this allowed me to switch them off and on again independently whilst leaving everything else powered on. Honestly, the key is patience as Europa has pointed out. For me, I would say it took 20 / 30 mins + per actuator for it to be calibrated settled and working as expected.

 

Below is what I did to get everything working as it should:

 

1. Rig up switch on each actuator

2. Set all actuator switches to off (in my case, this left all actuators in the closed position)

3. Get the system to call for heat

4. Make sure your flow has a decent heat (Mine was at about 50 deg)

5. Switch on the first actuator (LED flashes) for about 20 seconds, then off, wait 2 seconds and then switch on again

6. As above, after 2 mins, actuator LED flashing will slow and it will open fully

7. After about a minute, actuator will close (Don't get annoyed at this point)

8. Go away, leave it well alone for 20+ mins

9. When you come back, you should see that there is flow on the circuit

10. Leave the now calibrated actuator on and run through steps 5 to 8 for each of the other actuators in turn, avoiding the temptation to do more than one at a time

11. Leave the system for a couple of hours and you should find that it is then sorted and the valves as opening and closing to moderate flow

 

I was making two main mistakes:

1. Not waiting for long enough and when the valve does it's initial open then close, I was thinking it was not calibrated properly and doing the procedure again

2. By trying to do all circuits at once instead of one at a time, I think I was letting the manifold temp drop too much and therefore messing with the calibration.

 

Thanks very much for your help folks and I hope the above is of some use. I'm off to lie on my nice warm garage floor...

Edited January 20, 2022 by Tony Rae
Hit submit too early

[Dan F]

Does anyone know what happens with these actuators if, for example:

- The flow (from mixer) is 26C

- The return temperature is say 23C

Do they keep closing in an attempt to achieve delta-t of 7k and if/when they can't achieve this there is no flow?  Or what happens in this case?

 

The reason I ask is because when when using a low heat-curve and it's not particualy cold outside our controller keeps things ticking over but at lower flow temperatures anyway.  Currently (21C inside and 6C) outside it's using a target of 26C.  I don't currently have the Salus actuactors installed, but I was just wondering what would happen in this scenario once they are installed.  I guess I could try one on one of the loops, but just thought someone may know.

 

 

Edited January 23, 2022 by Dan F

[JohnMo]

They will open / close to achieve a delete T of 7, but I believe at low temps like you are speaking, the delta is maintained at 3 degrees.  Not sure of the exact switch over point between 7 and 3 delta T.

[Dan F]

7 hours ago, JohnMo said:

They will open / close to achieve a delete T of 7, but I believe at low temps like you are speaking, the delta is maintained at 3 degrees.  Not sure of the exact switch over point between 7 and 3 delta T.

 

Thanks!  Is this based on observation, or is this behaviour detailed somewhere?

 

I installed one on one loop last night just after posing on buildhub (i closed all other loops) and have been trying to understand it through observation, but so far it just seems to just be fully open all the time.  The weather-compensated flow temperature is currently 26.5C.  What would you expect it to do if return temperature is i) >23.5C ii) <23.5C?

[JohnMo]

From what I've seen it just ups or lowers flow to keep it the correct delta T

[Fly100]

Im sure i have read somewhere when the flow is sub 30c they operate a 10c differential to aid heat up time. Happy to be corrected.

[JohnMo]

say 4 degrees delta T below 30 degs (second post down)

 

 

[joth]

On 23/01/2022 at 16:48, Dan F said:

 

Thanks!  Is this based on observation, or is this behaviour detailed somewhere?

 

I installed one on one loop last night just after posing on buildhub (i closed all other loops) and have been trying to understand it through observation, but so far it just seems to just be fully open all the time.  The weather-compensated flow temperature is currently 26.5C.  What would you expect it to do if return temperature is i) >23.5C ii) <23.5C?

Hi @Dan F did you ever figure out what these actuators do if flow ~= return? Does it (virtually) shut off flow altogether, in an attempt to increase the delta? Obviously there's a cliff function here that zero flow will never achieve the desired delta! So I guess it's important it's calibration process accurately determines the point of minimum (non-zero) flow 

 

Context is I have these on UFH manifold working fine, but now considering adding them to my Fancoil manifold. These is a non-standard use case as:

(i) it's FCUs not loops,

(ii) it's really just used for cooling not heating (so risk any re-calibration would fail as it wants system set to maximum flow temp for calibration) and

(iii) the manifold is in series with a zone-specific buffer tank (system volumizer) required to stop short cycling but I have one manifold port set to use as a bypass so I can rapidly fill the buffer from ASHP (to minimum risk of short cycling) by having some flow bypass the (high resistance) FCUs just when the ASHP is running.

 

The motivation to convert the system to these is actually for the fast response times (30s vs many minutes on the current cheap wax actuators), not the auto balancing feature. it's a shame the standard Salus actuators are not as good mechanically (2W and 2min response time, vs 0.5W and 0.5min on the auto balancing variant). If there's a way to nobble the auto-balancers to act in "dumb" (fully open / fully closed) mode that'd be fine.

 

 

[Dan F]

On 14/06/2023 at 13:06, joth said:

Hi @Dan F did you ever figure out what these actuators do if flow ~= return? Does it (virtually) shut off flow altogether, in an attempt to increase the delta? Obviously there's a cliff function here that zero flow will never achieve the desired delta! So I guess it's important it's calibration process accurately determines the point of minimum (non-zero) flow 

 

Context is I have these on UFH manifold working fine, but now considering adding them to my Fancoil manifold. These is a non-standard use case as:

(i) it's FCUs not loops,

(ii) it's really just used for cooling not heating (so risk any re-calibration would fail as it wants system set to maximum flow temp for calibration) and

(iii) the manifold is in series with a zone-specific buffer tank (system volumizer) required to stop short cycling but I have one manifold port set to use as a bypass so I can rapidly fill the buffer from ASHP (to minimum risk of short cycling) by having some flow bypass the (high resistance) FCUs just when the ASHP is running.

 

The motivation to convert the system to these is actually for the fast response times (30s vs many minutes on the current cheap wax actuators), not the auto balancing feature. it's a shame the standard Salus actuators are not as good mechanically (2W and 2min response time, vs 0.5W and 0.5min on the auto balancing variant). If there's a way to nobble the auto-balancers to act in "dumb" (fully open / fully closed) mode that'd be fine.

 

To be honest I never really understood how these work. I primarily installed them as others recommended them and they seem to working.  I haven't tried to compare slab temperatures in different zones to try to assess if the auto-balancing nature of them works well because in practice this is going to depend on the positioning of the temperature sensors so might not be that fair of an assessment anyway.

 

In terms of the delta-t, my understanding is that, while they target 7K, at lower temperatures this delta is reduced.  They work just as well with cooling as with heating, but I haven't tried to observe what they are doing and if they are actively trying to keep delta-t up/down or both.  I'm also not entirely sure if this are correctly calibrated as the calibration instructions say you should calibrate at 35C+ and the temperature shouldn't fall during validation.   I guess I could remove the temperature sensors (or put both on the same pipe) and see what happens.

 

@JohnMo might have more insight than me though.  Looking back it was him who mentioned the 3K delta-t as reduced temps.

 

 

[JohnMo]

Basically they work as follows

 

They manage the flow rate through a loop by keeping a fixed delta T.

 

As zone valves close on a manifold this can upset the flow rate of the open zones. Auto balance valve just modulate to maintain the delta T of its loop.

 

At temps below 30 I believe the delta T is managed at 4 degrees, above that at 7 degrees.

 

I removed all mine and now operate the whole floor as a single zone. The actuators got in the way of balancing the flow rates to get room temps where I wanted them. i.e. I couldn't balance the system.

[Ewan]

On 23/06/2023 at 08:17, JohnMo said:

Basically they work as follows

 

They manage the flow rate through a loop by keeping a fixed delta T.

 

As zone valves close on a manifold this can upset the flow rate of the open zones. Auto balance valve just modulate to maintain the delta T of its loop.

 

At temps below 30 I believe the delta T is managed at 4 degrees, above that at 7 degrees.

 

I removed all mine and now operate the whole floor as a single zone. The actuators got in the way of balancing the flow rates to get room temps where I wanted them. i.e. I couldn't balance the system.

Please excuse the potentially silly question, but would you still use the wiring centre for the stat input in this scenario? e.g. the stat sends the input to the wiring centre, which signals the boiler and starts the pump, but the wiring centre doesn't mind that it's not actually opening any actuators?

[JohnMo]

As far as wiring and stats are concerned they are just an UFH actuator. But as a valve on the manifold closes or opens the salus valve open or closed to maintain a fixed dT across the open loops.

[Ewan]

Ah sorry, I meant in your scenario where you've removed all the actuators. Is everything else the same, you've just taken the actuators out and the wiring centre takes care of the pump and call for heat as normal?

[joth]

If you have a wiring centre it will still work after removing the actuators, but it's totally redundant; you can just pass the room stay call for heat straight through to the boiler relay input. (Modulo if there's a zone valve that needs to open you might want the delay start feature of a wiring centre, or to use the microswitch output of the zone valve to call for heat)

 

[JohnMo]

27 minutes ago, Ewan said:

Ah sorry, I meant in your scenario where you've removed all the actuators. Is everything else the same, you've just taken the actuators out and the wiring centre takes care of the pump and call for heat as normal?

Basically @joth says above. Nothing goes through the wiring centre now. It's just parking for a load of redundant wires.

 

I have no manifold pump or mixer either now. Thermostat is a boiler permissive only, the only zone valve in the system is part of the heating system is in a garden room. But that isn't allowed to call for heat, it can just close heat off.

[Ewan]

OK great. I can have both options available and see what works best, remove the actuators while keeping the wiring centre.

Doubt I'm going to be able to talk my plumber into open zoning the whole house, but at least I can do it afterwards.

If we have a bit of intermittent solar gain in one room, would putting auto balancing actuators on help potentially?

[Ewan]

Anyone seen the new Salus THB Ultra ABAs available in the UK yet?

Seem's they've done away with calibration need.

https://saluscontrols.com/gb/introducing-the-ultra-thb-auto-balancing-actuator/