R32 condensing units in boiler room

[hyperion]

We have a project enquiry and the only accessible place to install the four R32 condensing will be in a ventilated boiler room. Any thoughts as to whether there are any regulations preventing this? We are aware of the flammability risk with R32 in such a location. Just trying to get some information before we quote.

[Brian_UK]

My prime concern would be the correct ventilation of the boiler room, I'm assuming that the boilers are gas fired.

The heat rejected by the condensing units, CU, needs to be removed from the room so that there is no affect on the high level wiring in the plantroom. There are maximum temperature limits for cabling and electric valve motors etc. Also the boiler burners do not really want to see elevated air inlet temperatures.

Another problem can be during the heating season when to CUs are taking heat out of the plantroom. I have witnessed fully frozen units complete with ice laden drip trays.

If you are considering ducting the CU discharge out of the plantroom then you must ensure that there is compensating, positive, airflow into the plantroom to comply with the gas burner regulations.

[hyperion]

Thanks Brian, most helpful.

[Brian_UK]

Just been looking for more exact information.

A Refcom document may help, or hinder, ... https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.refcom.org.uk/media/1219/tb033-refcom.pdf&ved=2ahUKEwiApJnfhengAhWUThUIHUQDAUAQFjAWegQICBAB&usg=AOvVaw3nrjsfPgJS897V-z6S0Mx0

I'd forgotten that R32 is heavier than air so you need to be aware of drainage in the plantroom and is it below ground level. Also you may need to install leak detection equipment along with dedicated ventilation systems.

It just gets worse, sorry.

[hyperion]

Thnaks Brian, that is some helpful information that I can pass on.

[Rob White]

.

There are changes made in the newer EN 378 2016 standards.

See

https://www.agas.com/media/4504/en378-ior-guidance-note.pdf

It give a brief breakdown but one of the changes is "special location or Special plant room".

They differentialise the location of the room as "Special". Boiler houses might not conform to
that designation?

Regards
Rob

.

[hyperion]

Thanks Rob that is most helpful.

[Makeit go Right]

Can you not look at R410a kit.... Still need to look at safety issues but non-flammable gas rather than slightly.

[hyperion]

We ended up quoting R410A equipment.