We’re often asked by our customers…
Q: Why do you use hot water to heat your chamber as opposed to steam or forced hot air?
A: Our kilns utilize hot water because our drying methodology does not require extremely high temperatures. It is simply the best and most effective way to deliver the energy required to dry lumber using our schedules. Our maximum chamber temperature is 160°F and due to the larger surface area on our fin tube, we can come up to temperature just as fast as steam. The recommended hot water supply temperature is 180°F.
Q: How does the hot water heat the chamber?
A: The hot water is pumped from a boiler at 180°F to the chamber. Inside the chamber has copper fin tube that is adjacent to the circulating fan wall. The water circulates through this fin tube. The water flow is controlled by an electronic controller based on the desired chamber dry bulb temperature.
Q: What type of boiler can supply the hot water and do you provide the boiler?
A: The hot water boiler can be an open or closed type that operates at pressures around 18psi. The fuel of combustion can be natural gas, propane, fuel oil, wood waste etc. The wood waste boilers are popular since they use scrap wood. Nova Dry Kiln is an OEM distributor for a select few quality manufacturers of boilers and boiler feed systems. The customer may choose to supply his or her own boiler.
Q: How difficult is it to set up a wood waste boiler for automatic feed?
A: There is a lot to consider with automatic feed and it is probably not worth the increased cost on boilers that are below 800Kbtu. We have systems that meter in the wood waste based on demand from a hopper. There are variable feed and constant feed systems. Give us a call to discuss the best system to meet your needs.
Q: With respect to the smaller manual feed wood waste boilers, how frequently must you charge the combustion chamber?
A: For most feed stock, you will need to fill the combustion chamber twice per day. If the feed stock is real dry, the frequency could increase to four times per day. Some of the larger manual feed boilers can be fed pallets.
Q: What happens if I let the flame go out in my wood waste boiler?
A: Most of the time this does not present a big problem. Wood waste boilers are well insulated and our kilns hold heat quite well. Once the kiln is up to temperature and should the boiler flame out, one can expect the chamber temperature to drop 2°F per day if the powered vent is turned off. Once heat is restored to the chamber, simply pick up the drying schedule where you left off.
Q: Does Nova Dry Kiln provide a boiler connection kit?
A: Yes. This is optional. The smaller boilers (<300KBTU) come with a pump installed so the kit includes pipe valve and fittings. The larger boiler connection kit includes the same as above along with a pump and expansion tank.
Q: Can more than one kiln operate off of one boiler?
A: Yes. The kilns can operate off of a common manifold with their individual controls. Other loads can be piped in as well including heating a house, workshop etc.
Q: What is the insulation R-Factor for your chamber walls?
A: The R-Factor is anywhere between 22 and 37 at 75°F depending on the size of the chamber. More important, the overall thermal efficiency is quite high due to the tightness of the chamber itself. Our kilns operate at a slight vacuum assisting with the sealing of the doors. Please contact us for individual chamber BTU requirements.
Q: What materials does Nova Dry Kiln use for the chamber walls?
A: The small and medium kilns use our version of a structural insulated panel with 1/8” aluminum direct glue laminated to the inside and OSB on the exterior covered with white steel G-Rib Metal. The ceiling and door insulation provides extra moisture protection using extruded foam insulation. The large dry kilns use standard structural insulated panels for the walls with a gasketed aluminum lining on the interior. 1/8” aluminum is used on the side walls for protection. The ceiling and door insulation provides extra moisture protection using extruded foam insulation.
