I have heard several stories of training facilities that have had the barometric draft controls improperly installed. I have had some of the instructors tell me that students do not follow the instructions for installing barometrics and when the heating appliance fires off it actually shoots the barometric across the room. I had one instructor tell me that it happens so frequently that they have lines on the floor of their training lab to indicate the distances the barometrics have been shot out of the heating appliances.

To prevent this kind of activity, we have a very simple idea: READ AND FOLLOW THE INSTRUCTIONS. The Draft Control is a very simple device, one that can provide many trouble-free years of service. It does, however, have to be installed properly in the beginning and checked annually. Instructions for our RC Draft Control are less than two pages and include some nice diagrams for those of us who really like pictures.

All of our instruction manuals can be found at www.fieldcontrols.com. Just look for the Instruction Manual link under Contractor Tools. To schedule training on barometrics, call or email me or check out the training calendar on our website. We might already have some training scheduled in your neighborhood.

John Cotton

This week we talked with several people who want to know about running flue pipe on a downward slope if they use a power venter. You can use a flex pipe as long as you have a constant rise and it is well supported, but with a flex pipe you could get a droop in the pipe that will trap residual flue gases. These flue gases will condense and cause corrosion in the pipe and back into the appliance.

We recommend you use a rigid flue pipe with a power venter since you need to keep the constant 1/4 inch per foot rise on the pipe in accordance with the NFPA-211 codes.

John Cotton
HVAC Product Manager

The main cause of your indoor air quality problem may begin in your crawl space. The crawl space under a home is usually moist and dark, and the ideal space for mold and other microorganisms to grow and breed. You can start improving your indoor air quality by treating the area of the home where the problem begins. The crawl space is usually moist due to poor air circulation so you need to keep the air moving to reduce the moisture. When you reduce the moisture, you will reduce the amount of mold, mildew and other fungus growing in the crawl space. Also, if you keep the crawl space properly ventilated you will help prevent termite infestation and wood rot on the floor joists. If you are in an area where you have high humidity levels, circulating the air in that crawl space with the Eliminator foundation vent fan can reduce moisture levels in the crawl space. The biggest thing to help that crawl space and is to circulate the stagnant air.

John Cotton, HVAC Product Manager

I have been doing many training classes on the Field Controls products in various locations throughout the country. In these classes, I’m hearing about situations where the barometric is not installed correctly or the wrong one is used for the application. Many technicians have told me that the barometric is being installed in a bullhead tee on oil fired appliances. The bullhead tee should only be used on a gas atmospheric appliance. The purpose of the bullhead tee is to allow down drafts to be relieved into the room using a double acting barometric (such as the MG1 style), instead of in the burner chamber. If that down draft is allowed to go into the burner chamber it could blow out the pilot light. With spark ignition systems, you could get a build up of gases in the burner chamber that could cause a flame rollout or explosion when the gases reach the igniter. The MG1 style of barometric does the same job as a draft hood, but regulates the flue gases more precisely than the draft hood, giving you better control of the flue gases and maintaining proper efficiencies.

John Cotton
HVAC Product Manager

When we are troubleshooting problems with power venters, we usually find that they aren’t properly installed, set-up, and maintained. When someone complains about a power venter, we usually find that the installer didn’t refer to our instruction manual.

I know people who have had power venters properly installed, set-up, and maintained that have lasted over eight years without any problems. If a chimney is not properly constructed it can cause more problems than a power venter. When we talk to someone having problems with power venters, we always ask about the air flow adjustment with the damper plate in the back of the power venter. Most of them are surprised by this question and don’t even know where it is located. If the power venter is properly set-up and adjusted when the heating appliance is set-up, the power venter won’t give the problems that it is accused of producing. The power venters will allow the heating appliance to maintain proper efficiency, which a chimney can not, since heating appliances are tested with a maximum of a 5 foot chimney.

John Cotton
HVAC Product Manager

I was doing a training class last week on combustion air. I brought up the fact that according to the NFPA codes you need 50 cu.ft. of air per 1,000 BTU of heating, and that the space needs to be open. In other words, a 20′X30′X8′ basement is only large enough for a gas fired appliance up to 96 MBH or an oil fired appliance with a firing rate of .65 GPH. One of the technicians in my class stated that this was a large basement in that area which means that most appliances are installed in what is classified as a confined space.

The biggest comment we get is that the appliance is in a basement that is more than large enough to handle it, but that doesn’t take into account all the stuff that is stored in the basement. I have never seen a basement that didn’t have boxes of decorations, clothes, and other miscellaneous items stacked in it. When people say the basement is large enough they don’t realize that all this stuff reduces the amount of free air available for the heating appliance.

When looking at space to consider as confined space, we need to look at the total amount of free space that is available and not just the dimensions of the room. Remember that all the boxes of stuff reduce the size of the room.

John Cotton
HVAC Product Manager

The new primary with the quick disconnect seems to confuse a lot of people when trying to wire it with a CK-60 series control kit. With this new style of primary the orange wire is not wire nutted to the burner motor; it connects directly from the primary to the burner motor. With this new style, just disconnect the orange wire from the back of the primary and run that wire up to the WMO-1 and then to T3 on the CK-60 series control kit. You would then run a new wire from T1 on the CK-60 series control kit to the back of the primary control where the orange wire was removed. Then you would hook T2 to the neutrals in the primary.

John Cotton
HVAC Product Manager

I always love it when I am told that a power venter sooted up the side of a house. I never knew that a power venter produces soot.

Power venters are designed to exhaust the by-products of combustion from a gas or oil fired heating appliance. If the appliance is producing soot, the power venter will exhaust the soot. In most cases, we find out that the damper plate in the back of the power venter was never adjusted. I have never seen a case where the damper plate in the back of the power venter should not be adjusted. This is critical for an oil fired appliance as it will produce more soot than a gas appliance.

In most cases the draft setting is done with the barometric draft control only. The barometric draft control should be the fine tuning of your draft setting. The rough draft setting should be performed with the damper plate in the back of the power venter. Often, the power venter is installed by a builder or plumber when the appliance is installed, and then the service technician comes in later to set up the appliance and only does the appliance. The power venter seems to get overlooked by so many people until they start having problems with premature motor failures or staining issues. When this happens they always want to state that the problem is the power venter. If the power venter is properly set up, serviced, and maintained, it will last a long time and will NEVER produce soot.

I know a person who had a power venter installed on an oil boiler in 1989 that worked perfectly until the motor finally failed in 2006. This person made sure the power venter was properly set up, adjusted, serviced, and maintained yearly as per the installation instructions.

John Cotton
HVAC Product Manager

I’m John Cotton, your host. As Field Controls’ Product Manager, I love to talk shop. Product installations, product applications, troubleshooting, engineering, service…you name it, we talk about it. Everyday, Lynn Cahoon, Inside Sales Manager and I “field” calls regarding Field products. Each week, we will share some of the stories, ideas and solutions that come from these conversations.

We also travel to trade shows (NEFI, NAOHSM, ASHRAE, GAMA to name a few) and conduct training classes, where we get to talk shop face-to-face with our customers. Those experiences, too will find their way into this space. We look forward to sharing with you and encourage you to share your ideas as well. So anytime you feel the urge, drop us a line by using the comments link below. Feel free to include pictures, if you like.

Thanks for visiting. See you soon.

John Cotton
HVAC Product Manager