About Us
HMI HOYME Manufacturing Inc., since 1984, designs and manufactures unique energy efficient Motorized Air Control Dampers and devices for the Commercial and Residential heating and ventilation industries. Friendly to the environment plus meeting ventilation requirements, HMI HOYME Dampers and accessories have proven to be well accepted by the HVAC industry across the United States and Canada.
The Model National Energy Code for Houses (Canada) and the Use of Motorized Dampers
by Cliff Hoyme
When I renovated my country home 25 years ago (1975), I followed the (then new) National Gas Code which required a passive Fresh Air Supply Duct for combustion. Fire requires fresh air to burn. But when the fire is not burning, this passive Fresh Air Supply Duct into my basement proved to be an uncomfortable cold air problem, then, and still proves to be an uncomfortable cold air problem in many homes today. With temperatures reaching below minus 20ºC several times during the winter months, passive fresh air inlets, besides being uncomfortable, waste energy, place extra strain on mechanical equipment and at times cause water pipes to freeze.
Extra energy is required to keep this dwelling warm. Extra energy compounds the problem when we consider the greenhouse effect of burning a non-renewable resource (i.e. natural gas) to heat uncontrolled cold air. The amount of passive air through one or two Fresh Air Supply Duct into one house, by itself, is not much, when we consider thousands of homes, in one province alone, each using extra (wasted) energy that could be saved, the total amount of wasted energy is great. It doesn’t require space age science to calculate or to solve this problem.
The Model National Energy Code for Houses 1997 (MNECH), has addressed this problem in Article 5.2.3.1, which requires the installation of automatic Dampers. In fact MNECH places a high priority on the control of inlet air including inlet air for combustion. A letter received from Mr. John Haysom, Technical Advisor to the Committee responsible for MNECH, states that ‘…the Installation of (Certified) Motorized Dampers on Combustion Air intakes for gas appliances is required for compliance with MNECH…’. Uncontrolled cold air, regardless through what duct it passes, is uncomfortable and requires extra energy to heat.
Do Dampers on Combustion Air Supply Ducts add to the ‘Sick House Syndrome’?
Answer: The Combustion Air Inlet Duct is for safety, designated to provide fresh air for complete combustion. This Fresh Air Duct is required by provincial codes and regulated by National Fuel Codes. Provincial Codes, however, require an additional and separate inlet duct for ventilation air. If the Combustion Air Duct was to serve both combustion and ventilation air, then only one damper would probably add to the ‘sick house syndrome’. The ‘Sick House Syndrome’ sometimes develops from too much fresh air causing many people, for the sake of comfort, to permanently plug both inlets, Combustion and Ventilation Air. This is indeed an unsafe practice. By using two Motorized Dampers, as required by MNECH, eliminates this unsafe practice and also provides fresh air when required. Controlled fresh air flow using Motorized Dampers usually eliminates the ”Sick House Syndrome’.
Are Dampers cost effective?
MNECH refers to it as life-cycle costing’ (payback). The Spring 1998 edition of Construction innovation’ published by the NRC’s Institute for Research in Construction states that at the heart of MNECH is ‘…based as much as possible on life-cycle costing, taking into account such factors as climate, energy costs and construction costs.’
Local testing of dampers for payback was completed by The University of Alberta, Engineering Department, Edmonton in October 1994 and by the Alternative & Retrofit Energies Incorporated, Calgary, in January 1987. Energy savings showed a reduction in fuel consumption of 5% to 20% during the winter months. This translates into dampers not costing but actually paying for themselves over a period of time by the energy saved.
Of greater concern is the effect that wasted energy placed on the environment. In a recent conversation, Mr. John Haysom, Technical Advisor to the Committee responsible for MNECH, commented that newspaper articles are now talking about wasted energy and its affect on the environment to even cause irregular climate changes. He also stated that in light of renewed interest in energy conservation and its effect on the environment, several provinces and the City of Vancouver are re-evaluating the merits of implementing MNECH.
Hoyme Manufacturing Inc. has been producing energy saving products for the past 20 years. Thousands of CSA approved combustion and ventilation air control dampers have been sold across Canada and the US. The effectiveness of these dampers to add comfort and save energy, especially the combustion air damper, is evidenced by the fact that thousands of home owners, including CSA personnel, have installed a motorized combustion air and/or a fresh air inlet damper.
After realizing the benefits received from these dampers, many customers have made comments such as: ‘What’s the matter with the heating industry? Why didn’t they put this damper on my house when it was built? My basement has never felt so comfortable! These dampers should be demanded on all installations’.
In the light of recent discussions on wasted energy, its effect on greenhouse emissions and most recently on climate changes, it is now prudent and timely, I believe, for all governments to adopt MNECH which is designed to protect the environment. MNECH is there for governments to accept. It is my hope, therefore, that all governments will harmonize the new MNECH into their own Building Code, and to include Article 5.2.3.1. requiring Motorized Dampers on all passive air inlets, combustion air included. The homeowner benefits from increased comfort plus a reduction in energy costs. Everyone benefits by developing and preserving a clean and friendly environment protected for all to enjoy.