Post a reply to the thread: Define Twinning
You may choose an icon for your message from this list
Please enter the name by which you would like to log-in and be known on this site.
Please enter a password for your user account. Note that passwords are case-sensitive.
Please enter a valid email address for yourself.
Will turn www.example.com into [URL]http://www.example.com[/URL].
Bite me. Running flexible lines that penetrate the cabinet is wrong. So you subbed the work out and the sub did it wrong. You are responsible.
Originally posted by troyorr Get a qualified person in there to replace that illeagle gas line installation. get a qualified person to post for you that can spell illegal gas lines were subbed out to plumbing co. and yes there were legal when this job was done (3 years ago). the only code requirement that Has changed is that you have to run hard line from the gas valve to a minimum of 2" out of the cabinet then you can run flex. i dont know where youre from but around here (central TX) they're all done this way.
Get a qualified person in there to replace that illeagle gas line installation.
Originally posted by onesidedcoin Inventive idea for a job.I have done serveral twins over the years and I am interested how you set up the controls.Normaly the boards communicate by running feed to each board thus the fan speed is the same for the mode the system is in.Can you run the jumper to more than two boards?Also did you add hi temp limits on the blowers? the stat has its own transformer that controls the units thru relays mounted in the box on the back wall. master furnaces are controlled in parallel off of said relays. all furnaces have high temp limits on the blowers wired in series to heating control relay coil and freeze stats on all coils wired in series to cooling control relay coil. if you have autocad email me at: ductmaster2112@yahoo.com for details if you like.
Re: Bypassing Air all fans run simultaneously in heating and cooling. furnaces have belt drive, single speed fan motors. each triplet of furnaces have a master and 2 slaves... system sequence of operation in heating mode is: 2 master furnaces against back wall start then all 6 fans start..... 2nd stage heat is 2 furnaces in foreground gas valves, inducer etc.. system sequence of operation in cooling mode is: all 6 blowers fire off simultaneously. stage 1 - both 20 ton condensers (with electric unloaders) start unloaded with 4 solenoid valves energized. stage 2 - remaining 2 solenoid valves energize and load remaining cylinder(s) [Edited by chriskmb5150 on 12-20-2005 at 09:14 PM]
Re: Bypassing Air
Bypassing Air Question: Can I assume there is staged capacity control for heating and cooling? If so, what would be the sequence of operation ...say 50 capacity ...assuming some fans on and some fans off...would this let supply air into and back flow through the "turned off" furnances. Assuming they are connected to the same connected supply ductwork? Does this allow the "turned off" fan motors to free wheel when not in operation? [Edited by mss control on 12-20-2005 at 02:14 PM]
Bypassing Air
Looks good. Try and get pic of old equip. next time. Makes the new stuff look even better.
Inventive idea for a job.I have done serveral twins over the years and I am interested how you set up the controls.Normaly the boards communicate by running feed to each board thus the fan speed is the same for the mode the system is in.Can you run the jumper to more than two boards?Also did you add hi temp limits on the blowers?
Originally posted by mayguy Wouldn't it be cheaper to just just an air handler in rather the furnace that will not be used for heating??? I'd think that's a waste?? one of the main criteria of twinning is that you use identical units...identical airflow etc.. not really a waste if you think about the when/if one of the operational furnaces needs a heat exchanger, inducer motor, gas valve etc
Wouldn't it be cheaper to just just an air handler in rather the furnace that will not be used for heating??? I'd think that's a waste??
Originally posted by mayguy Originally posted by chriskmb5150 Originally posted by mayguy Looks good... BUT>...... 4 out of 6 is vented. only 4 furnaces are used for heating, all 6 are used for cooling. So the two are just air handlers? Or gas furance that is not hooked up? furnaces that arent hooked up. Basically just blower coils
Originally posted by chriskmb5150 Originally posted by mayguy Looks good... BUT>...... 4 out of 6 is vented. only 4 furnaces are used for heating, all 6 are used for cooling. So the two are just air handlers? Or gas furance that is not hooked up?
Originally posted by mayguy Looks good... BUT>...... 4 out of 6 is vented. only 4 furnaces are used for heating, all 6 are used for cooling.
Originally posted by wannagetstarted wow that looks nice , i think zip ties would look better around them line sets, but either way it looks nice... hey can any one explain twinning a little better to me? twinning is using 2 or more smaller systems running together to make one larger system. such systems use one thermostat and usually share common return and supply ducting. most manufactors sell twinning controls for their equipment. carrier makes a neat tripling kit but their twinning kit sucks. for instance: at this job we took out a 40 ton air handler that heated and cooled a church sanctuary. these new units are in a second floor closet.. the old air handler was on the first floor directly under these units with the return air duct running in the 1st floor ceiling and the supply duct coming up thru the floor behind where im standing and going thru the 2nd floor ceiling into the attic space above me and running overhead where these units are sitting and to the sanctuary attic space. well, the church wanted to use the mechanical room on the first floor for storage so we sugggested using this closet on the second floor but we couldnt get such a large 40 ton air handler in there so we used 6 - 7.5 ton units. we cut a large hole in the floor and ran a duct down from floor level to the top of the existing return air duct in the attic space below then built this wooden platform to use as a return air plenum. then after we set the furnaces and coils we manifolded all of coils the into the existing supply duct in the attic above. hope that explains twinning a little better. Originally posted by wannagetstarted hey what is that on the sunction line at the top? im barely in the field so i want to absorb as much info i can get thats where the txv sensing bulbs are... the bulge is just armaflex.
Originally posted by wannagetstarted hey what is that on the sunction line at the top? im barely in the field so i want to absorb as much info i can get Solenoid valve. Its on the liquid line.
Perhaps 4 are used for heating and 6 used for cooling?....
Looks good... BUT>...... 4 out of 6 is vented.
hey what is that on the sunction line at the top? im barely in the field so i want to absorb as much info i can get
wow that looks nice , i think zip ties would look better around them line sets, but either way it looks nice... hey can any one explain twinning a little better to me?
I prefer duct tape over wire ties. Nice job
Forum Rules
