Concrete Curing Room

[PhilAtBriggs]

Hi all,

I have set up a curing room in my lab using a walk in freezer. The issue I am now coming across due to the season is keeping the room at temperature. I could use some insight on how to heat the room with out posing a shock hazard and with out drying samples close to the heat source.

I was thinking of making my own hydronic system using a tankless hot water heater and baseboard radiator elements on a closed system.

 

[concretemasonry]

Obviously you will need to also control both the temperature and humidity and have a constant recorder for conditions. - the more mass in the structure, the better for stability and economy. A walk-in door could be left open too long if you have a lot of activity and large, bulky samples.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[darthsoilsguy2]

if you have any friends in testing laboratories, visit them. The hard part is getting the misting right. you have to get coverage and the particle size right. Once you have that, controlling the temp is done by picking a water temp sweet spot. continuous recording of temp/humid is needed as cm said. even after you dial it in, you will need to regularly check on it... the room will behave differently empty, half-full, and full because cylinders make heat and also bring their thermal mass temperature to the room when they are brought in from the field.

 

[Ron]

Use alternating hot and cold water, controlled by a thermostat, to control the temperature. Thermostat must be a very good one with a tight temperature range. Thermostat controls electric valves for the water. Systems can be separate or single piping to spray nozzles once inside the room.

 

[concretemasonry]

Phil -

First - How large is the freezer and what is the construction?

Short term controls are really not effective controls unless you have a minimal amount of mass for thermal and moisture storage in the surrounding structure (under, over and around). Hot and cold water will be not be effective unless you have a good control over a quick closing door system. No matter how much insulation, just opening a door can put you back to close to zero and the samples can actually lose some moisture even after the door is loading/unloading door is closed.

There are some very good standards in the industry documents for certifying room for testing labs. The standards are quite loose, but adequate for testing certification.

If there is any question about your curing, a continuous recording temperature/moisture system is well worth it, even if it is only the air temperatures. If the circulation is not good, you may need high low, middle and low sensing locations. This is usually for large chambers.

I have been involved is curing of concrete products, curing systems and testing results and some of my opinions are a little aggressive when it comes to controls, installations and operations, but there is always a unique situation. - An engineer friend even had a "guarded hot box" for testing walls for actual insulation values for wall assemblies in his garage for years. He even had to acclimate the wall samples prior to the actual testing procedure to meet schedules.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[bb29510]

we have these mizters we get from the construction material suppliers, they are like squirrel cages in a water pan, that creates a london fog, serious you can't see three feet, then there a heat pump unit on top, special unit, keep its 72 degree. the heat pump wilt produce cold or heat other than 60-80

 

[dicksewerrat]

If possible, build an 'airlock' outside the freezer to reduce losses inside the freezer.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com