Can you install A/C condensing units in Boiler Rooms

[nottsacgirl]

Afternoon all,
Seem to remember from my contracting days that you shouldnt do this. Can anyone please confirm if this is still true, and if so does it also include fridge pipework. Also if so, is this law or just good working practice that we're talking about?
Appreciate your help on this.

[lana]

Hi nottsacgirl and welcome to the RE.

Air cooled condensers must be installed in areas where there is fresh air available for inlet to the coil and there is proper discharge area for the hot air coming out of the condenser. So if boiler area is hot then simply the condenser will not work.

If you are talking about water cooled condenser then it may be possible with proper insulation, if area is warmer than the condensing temperature.

Cheers

[US Iceman]

There may be some safety regulations that stipulate refrigerant cannot be in the same area as boilers or other devices where a flame is or can be present.

Lana touched on the other topic that could limit the acceptability of this too.

[nottsacgirl]

Thats great thanks for your help on that one!

[mecassa]

I've seen ref condensing system installed in boiler rooms, the boilers need enough supply air to overcome the exhaust fans though to minimize neg pressure.

[The Viking]

OK, taking my CORGI hat on now....

The answer is yes, BUT you do open up a whole can of worms.
CORGI's ventilation spec is there to limit the maximum boiler room temperature as well as providing air for the combustion. There is a legal max temperature which the boilers are designed for but I can't be ars@d to look it up just now.

So if you decide to fit an outdoor unit in there, you have to increase the ventilation in order to keep the temperature down and by the time you done this it's probably better to put it somewhere else in the first place.

[nottsacgirl]

Viking - my concerns were more along the lines of is there a legal requirement in case there is a leak on the a/c system releasing flammable gas in an area with potentially naked flames?

[Sledge]

A boiler room has requirements for

-combustion air to be made available to the boiler ducted to within 18 inches of the floor. This ducting is sized depending on boiler max input btu and is designed to supply adequate combustion air.

-Dilution air to be supplied at ceiling height, also sized based on firing rate of the boiler.

There is no requirement for air to cool the boiler room. The cooling is actually achieved by the constant air changes, as air is drawn from the room into the combustion chamber and vented out the chimney, and is replaced by outside fresh air being supplied to the room.