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Re: Fraser Johnston- gas valve
Dog Mom. Timmie KNOWS....Give him a call, write down exactly what he says (70 years experience), buy a Book or manual from him...(Cheap!) Happy New Years! Keep us posted on this. Mad Dog 🐕
Re: Thread sealant cure
Makes sense. Thanksrealliveplumber said:The cure time is as short as you need it to be to get the heat on. The sealant is in the root of the threads.If the threads dont leak, the oil cant get to where the sealant is.
Dave_61
1
Re: Pressuretrol vs Vapor Stat
When I had my Smith steam boiler installed I removed the Vaporstat from the Burnham and had it put on the mew Smith G8. Knowing that rust never sleeps I put Steam Master into the Smith when it was new and a decade later the water is clean with a very light tint so I'm hoping that Smith outlasts me.
Bob
Bob
BobC
2
Belated Merry Christmas and a Happy New Year
Sorry I was away for Christmas but here to wish everyone a happy and prosperous New Year, At 84 years old I am happy to be still going strong and still doing training.
Re: Fraser Johnston- gas valve
The replacement is a Honeywell (now Resido) VR8205A or a VR8300A gas valve both those valves include the gas shut off so you can get rid of the "A" Valve and Pilot (B) valve also the regulator ahead of the valve (the new valve includes a regulator). The thermocouple can be attached to the new valve. Call me at 401-437-0557 if you have a question.
Re: Fraser Johnston- gas valve
There are numerous possible problem items that would cause the gas valve not to open. I will do my best to list them. First off, Fraser-Johnston was not a big name in my area but almost every furnace from that era worked the same and had similar parts.
#1 The pilot is lit since it has it's own gas supply and is not affected by a control malfunction. That pilot heats a thermocouple that is supposed to supply a small voltage to the safety pilot/gas regulator. (See that small line at the bottom of the device with the red cap). If the thermocouple does not produce the correct amount of electricity that device will not operate, and gas will not flow.
#2 In the 2nd set of pictures in your 6:21am post, that device in pictures #2 & #3 at the top right with the wiring attached, is a 24 volt transformer that provides voltage to allow the furnace to operate. The voltage leaves the transformer and flows through the thermostat, limit devices, and the gas valve and returns to that transformer to complete the circuit allowing the furnace to operate.
#3 In order to trouble shoot your furnace you need a volt meter to see where the voltage is being stopped and not allowing it to complete the circuit. If there is 24volts on the gas valve and it does not open it may be the problem. Any descent ist year apprentice could trouble shoot your furnace and see what device is at fault. The biggest problem is that a lot of the young service guys have not seen a set-up like yours. They are too young not an old retired guy like me.
#4 What you need to find is an older gent that has experience with older equipment. If the problem is the gas valve a new type combination valve could be installed but there are other devices that may be malfunctioning. If the chamber in that furnace is not cracked or deteriorated then fixing the furnace is your best and cheapest option. Go find a good and reputable HVAC company that wants to fix that furnace and not just replace it.
#1 The pilot is lit since it has it's own gas supply and is not affected by a control malfunction. That pilot heats a thermocouple that is supposed to supply a small voltage to the safety pilot/gas regulator. (See that small line at the bottom of the device with the red cap). If the thermocouple does not produce the correct amount of electricity that device will not operate, and gas will not flow.
#2 In the 2nd set of pictures in your 6:21am post, that device in pictures #2 & #3 at the top right with the wiring attached, is a 24 volt transformer that provides voltage to allow the furnace to operate. The voltage leaves the transformer and flows through the thermostat, limit devices, and the gas valve and returns to that transformer to complete the circuit allowing the furnace to operate.
#3 In order to trouble shoot your furnace you need a volt meter to see where the voltage is being stopped and not allowing it to complete the circuit. If there is 24volts on the gas valve and it does not open it may be the problem. Any descent ist year apprentice could trouble shoot your furnace and see what device is at fault. The biggest problem is that a lot of the young service guys have not seen a set-up like yours. They are too young not an old retired guy like me.
#4 What you need to find is an older gent that has experience with older equipment. If the problem is the gas valve a new type combination valve could be installed but there are other devices that may be malfunctioning. If the chamber in that furnace is not cracked or deteriorated then fixing the furnace is your best and cheapest option. Go find a good and reputable HVAC company that wants to fix that furnace and not just replace it.
Re: Picking Gas Furnace
Isn't the OP's point that the furnace blower needs to be able to move enough CFM (400 cfm per ton AC as a rule of thumb) to handle the cooling load? So a 3 ton AC unit like the OP has needs a furnace blower that can move 1200 CFM. And too small a furnace may not be able to deliver that CFM.
This is what the OP thinks, but it is wrong. You can get a blower that gives you 1000 CFM for cooling AND runs at a lower speed for heating. Or just use 1000 CFM for both. They make two stage 40kbtu high, 28kbtu low furnaces, that could actually use 3 speeds, 2 for heating, 1 for cooling. Contractors should know how to do this. These are basic units. 