BMS system - from 90s to modern? Bring in house?!?!?

[PotNoodleTech]

Hi All. Our BMS is rubbish - very unreliable the individual bits of hardware dotted around are up and down, temp sensors failing, etc.

 

We have to pay a third party as the system was originally put in by the LA but we get terrible value out of those support contracts.

 

The physical hardware is ok, reliable as on boilers (if old) it always seems to be the third party electronics and garbage 90s software interface that lets us down.

 

Im thinking outside the box now and thinking surely there must be a better way - maybe bring this in house and roll something with a modern BMS, i don't know home assistant or some other modern BMS.

 

How to you do it? anyone brought BMS in house? Anyone using freely available software like home assistant?

 

When the system at home works 100x more relaibily than the ££££££ system in school it makes me think maybe we should be looking at these home systems instead for inspiration!!

[dmj]

^I'd do that, but most here don't like the homebuild stuff and only want vendor supported systems.

I guess it depends on you technical aptitude and the schools appetite for risk if you leave.

[andy_b]

^I'd do that, but most here don't like the homebuild stuff and only want vendor supported systems.

I guess it depends on you technical aptitude and the schools appetite for risk if you leave.

 

The first time my "home" solution fails guess where the blame will be placed, no thank you.

[Andrew_C]

What dmj says about when you leave, plus a commercial system is likely to be orders of magnitude more complex than a domestic system, unless you are in a very small school.

 

Our controls are kind of clunky, but covers many boiler rooms, each with many zones.

[TheRobins]

Had our BMS upgraded 18 months ago, along with refurbishement of our main boiler room (as part of a large CIF bid). The BMS was then installed also in the other plant room. However BMS systems are complex, and require an awful lot of knowledge to design and program. When you start interfacing multiple zone, pumps, CO2 detectors and boiler controls its well out of the scope of your Nest or Hive system. The cost just for controls was well over £7000 and still required some tweaks 12 months after install, once we knew more about the system and how it works. Some of the things I still manage today is the room CO2 monitors that open ventilation flaps in classrooms once the room CO2 is high, but the outside temp is above a certain level. Ours is based on the Trend IQ4E system.

 

Not sure where you are located, however the engineer we used for design and build is based in Bristol. There are not many around who do it, and when they do their day rates are interesting.

Edited February 8, 2024 by TheRobins

[mavhc]

Home and Work solutions are the same, just Work ones you can pay someone £1000 to not be able to fix it and get a new part.

 

My rules: No batteries. No wireless.

 

Just stick to standards and document everything. PoE, MQTT, RS423, Modbus

[dmj]

Home and Work solutions are the same, just Work ones you can pay someone £1000 to not be able to fix it and get a new part.

 

My rules: No batteries. No wireless.

 

Just stick to standards and document everything. PoE, MQTT, RS423, Modbus

 

This is fair, I don't see a reason why something like home-assistant shouldn't scale. You'll need things like High Availability MQQT and that's propriety so even homemade stuff you'll end up spending something on it if you do it properly.

[PotNoodleTech]

^I'd do that, but most here don't like the homebuild stuff and only want vendor supported systems.

I guess it depends on you technical aptitude and the schools appetite for risk if you leave.

 

I take your point. Not sure about being afraid of risk on a new system, when the current BMS barely works?

 

If we are risk adverse then we will never do anything?

 

But yeh it doesnt seem like there's any easy routes when it comes to BMS at all and the the DIY part of it would look very complex and not for the faint hearted I grant you that!!

[PotNoodleTech]

Had our BMS upgraded 18 months ago, along with refurbishement of our main boiler room (as part of a large CIF bid). The BMS was then installed also in the other plant room. However BMS systems are complex, and require an awful lot of knowledge to design and program. When you start interfacing multiple zone, pumps, CO2 detectors and boiler controls its well out of the scope of your Nest or Hive system. The cost just for controls was well over £7000 and still required some tweaks 12 months after install, once we knew more about the system and how it works. Some of the things I still manage today is the room CO2 monitors that open ventilation flaps in classrooms once the room CO2 is high, but the outside temp is above a certain level. Ours is based on the Trend IQ4E system.

 

Not sure where you are located, however the engineer we used for design and build is based in Bristol. There are not many around who do it, and when they do their day rates are interesting.

 

Thanks that all makes sense.

[dmj]

I take your point. Not sure about being afraid of risk on a new system, when the current BMS barely works?

If we are risk adverse then we will never do anything?

But yeh it doesnt seem like there's any easy routes when it comes to BMS at all and the the DIY part of it would look very complex and not for the faint hearted I grant you that!!

 

I agree, loads of what we do is from scratch. Some aren't so comfortable with that, which is understandable if they doubt their own ability to make a reliable system or don't have the support of their school to do that.