Yes. 10 year parts and 1 year labour.
Yes you can blow off your filter using your compressor.
Just do it in reverse of the direction of airflow. That means blow it off from the mesh supported side. This will push particulates out the way they came in. Your not going to damage your system.
It is far better to clean it than leave it in dirty. That is the true danger here. Reduced airflow is far more damaging than a little dust could ever be. So if you cant buy a new one you are better off using your compressor to clean your old one.
There are a number of factors that one can consider when buying a furnace.
When considering price from a contractor you are buying the product and the installation. The cheaper the furnace, typically the poorer the install. To the average consumer you may not be able to tell if you have a poor install. A poor install means you will not get the rated efficiency and may have maintenance issues in the future. We do heat exchanger inspections and efficiency tests on all units I work on. The units that are not running well are the ones that have issues breaking down and cracked or corroded exchangers.
To sum this up, a properly set up furnace is part of the purchase. Installing a furnace properly cost more money than just slapping a box to your duct work and collecting a check. Every contractor will assure they are doing the right way. So, you have to do your work before deciding on a contractor.
There are two ways you can smell gas from your furnace. The first way is that you have a leak in one of the fittings or gas valves in the furnace. You can buy a leak detector and soap up every joint and look for bubbles. I usually can get pretty close by smelling around the piping and then start soaping. I can also use my flammable gas detector or “Sniffer”, this is a pricey tool for a homeowner.
You can also call a furnace repair person or plumber to check for leaks. This is preferred because if you do call the gas company and they find a leak, they will shut off your gas. Then it is hard for the gas technician to find the leak and then test the leak without gas pressure. There will be an extra charge for pressurizing the system with inert gas to check with our gas pressure. After the tech has repaired the leak, the gas company will come back, turn on the gas and recheck. Some times new leaks are found and the tech will have to return to repair and start the process over.
The second way to smell gas is from a furnace that is not firing properly. This can come from a delayed ignition or a furnace that is operating at high gas pressure. When it lights off, a bit of unburnt gas puffs out of the unit. For this, I would call a furnace repair person as well.
Pretty much, most manufacturers are going to be similar in quality. They are all using parts from the same few vendors, and seldom actually produce more than simply the case and heat exchanger. All other parts are outsourced. Warranties are normally the same across the industry, but check carefully, as often, warranties on non-owners occupied hones are considered commercial use and are much shorter. Be aware that most brands have twins…Trane/American Standard, Carrier/Bryant, RUUD/Rheem…the list goes on and on . . Same unit, different names and paint.
Really, you are mostly buying the contractor, not the furnace. Contractor is the one who will give you a great or poor experience. Check their references. Make sure they are planning on pulling a permit and having their work inspected and that he has decent liability insurance, at least twice the value of the property. Make sure it’s a real company. The name of the company on their vehicles (magnetic signs don’t count), workers comp on his guys, licensed by the proper city authorities, doing this work full-time, not as a part-time side job. You want someone you can count on to be available even years AFTER the install, someone relying on and committed to the operation of his business.
Murphy’s Law says that your gas furnace will fail on one of the coldest winters days, and that it could be days before you can get service, because every HVAC service company is backed up with people having the same problem.
By getting your furnace inspected by a competent and reputable HVAC technician, you can have furnace components that are on the verge of failing replaced, as well as having flame sensors and other components cleaned and adjusted as necessary.
You should have your gas furnace serviced at least every two years.