Migrating from Ademco

I am migrating from an Ademco with a 2000 ohm EOL resistor on the fire zone to an Elk M1 with a 820 ohms (2-wire smoke on Zone 16).
The problem is that I cannot find the resistor, it's probably somewhere in a wall/ceiling.
Is there a way to make it work? I see the 4-wire smoke requires a 2200 ohms. 
Can I add add a 200 ohms in series and use a regular zone (ignoring the power)?
Thanks for any help on this, my wife seems to be reluctant to me opening the walls

Have you removed the smoke detector to see if the EOL resistor is connected to the terminals of the detector (which is where it should be).  I'd be very surprised if the resistor is buried in the wall or ceiling somewhere.  There's just no reason to do that. 
 
Just to be sure, disconnect the two wires from the smoke detector and short them together, then measure the resistance across the pair back at the panel end (with that end disconnected, too).
 
If it is a 2-wire smoke detector, you may need to replace it anyway since the M1 only qualified for operation with certain models of 2-wire smokes (see p6 of the M1 manual).

The 2 wire smoke statement would need to be tempered with the OP taking an inventory of the existing (make/model) and in the case of System Sensor (GE/UTC/Interlogix discontinued their version I believe) there are modules that would allow "non-compatible" detectors to be used and compliant on the M1.

That said, if the units are 10 years old or older, or approaching that age, they're supposed to be replaced anyhow.
 
As far as EOLR location, generally it'll be at the furthest detector (physically) from the panel, however it may be possible to be elsewhere, such as if the installer used 4 conductors and either fed back to the panel or through a heat detector, etc.

Thanks to both of you.
I finally found an additional sensor, my fault for not looking hard enough, I apologize.
The EOL was there. Only 2 wires to this detector (2 pairs in the others), so it's indeed the end of the line.
I replaced it with the 820 ohms, but Zone 16 is still Not Ready. The green light is blinking on each smoke when connected, and the 2 wire measure 820 ohms when disconnected from the panel.
I will get the model numbers of the heat and smoke sensors and contact Elk for compatibility.
DEL is correct, they are over 10 years old and probably need to be replaced anyway.
 
Question: I have 5 smoke and 4 heat sensors. Do the heat sensors need to be replaced as well every 10 years?
 
Bonus question: There are quite a few cables which were not connected to the old panel. In particular, three 2-wire cables measure 8-10 Mohms. Is this value typical of a particular device? All the following are accounted for: all doors, 10 glass breaks, 2 motion sensors, 3 keypads, and a siren. There does not seem to be any window contact (all opening windows are crank operated).
 
Thanks for your help, as you can see, I am not too versed in this! 

As far as "not ready" I would check the jumper on the panel for correct placement first.
 
Heat sensors are generally OK, however most are fusible link types and testing usually ends up destroying them. NFPA's standpoint on this is fusible link types are supposed to have a percentage removed and tested by a lab.
 
Since you have 2 wire detectors due for replacement because of age, the best option IMHO would be to get COSMO2W detectors and appropriate module. Gives you smoke/heat/audible, tandem ring and CO detection with no new cables to pull. It really isn't worth attempting to pull sensitivity out of them and buying the replacement parts to rebuild the chambers. We're not talking an entire college campus or building floor here.
 
You're looking at about $300 worth or parts to replace your entire fire loop. Which is more expensive, that or what happens after a fire?
 
As far as the spare cables, the value indicates an open circuit (Megohm resistance). They are spares of some sort, but it's anyone's guess unless you tone them out to find them or physically locate them.

>>> As far as "not ready" I would check the jumper on the panel for correct placement first.
I removed the 2 wires, then connected a 820 ohm across zone 16, still Not ready.
Then I moved the jumper to the left and inserted a 2200 ohm resistor, the system is now Ready. 
 
>>>You're looking at about $300 worth or parts to replace your entire fire loop.
These sensors seem quite powerful since they have CO as well, but how are you coming with $300? Looks like these units are $80 each (I have 5), plus 4 heat sensors and the interface module at $40 each, give or take?
 
As far as the spare cables, the value indicates an open circuit
>>> OK, I will leave them alone for now.
 
Thanks, Del, I do appreciate your time!

If you moved the jumper and installed the 820 ohm resistor at the panel and still had a faulted zone, either you have a bad panel OR you have the wrong value resistor. Would also check the loop voltage with the resistor installed and zone definition changed, been a while since I had to think hard about what the state of the M1 is when not programmed and putting devices like 2W smokes on them.
 
You'd have to branch the heat detectors off the zone if you were doing tandem ring. I won't get into the fine details.
 
I grabbed the wrong number. Was looking at I3 detectors, which would be compatible with the COSMO module also. About $40 vs. $80 retail via resellers I3/I4. Heats are about $10-15 each new.

I am a little confused...
You say I have to remove the heat detectors but you give me the price for these detectors (let's not worry about the price of the units themselves).
 
If I understand correctly, I have 3 scenarios:
- Either I duplicate my existing setup, replacing the smoke and the heat detectors for the same type. Same thing, except new. One zone (Zone 16).
- Or I mix COSMO2W (w/ CO for the bedrooms) and 2WTA-B elsewhere (including in the attics/kitchen where I currently have heat sensors) plus a COSMO interface module to end up with 3 zones (smoke, CO, monitor). A better setup indeed.
- Last would be to use COSMO2W everywhere but I am not sure it's necessary. Maybe in each attic with a furnace?
 
Is this correct?
 
RV

First would be to see what is listed for 2wire detectors on the M1. (answer is pretty much old and discontinued items, Elk hasn't really kept up with their UL there) and replace as-is.
 
Second would be use the COSMO and I3/I4 detectors and then not use the tandem ring portion of the hardwired heat detectors stay on the same loop.
 
2A: would be to separate out/disconnect the heat detectors and run cabling to be separate from the smoke detector loop, then provide tandem ring capabilities to the smoke detectors.
 
You would not install the detectors in unfinished, unconditioned space like attics or similar or in kitchens. That's why there's heat detectors, most likely.
 
If you're not going to re-feed heat detectors (or not possible) then the best would be to leave the heats as-is, put some I4's out there (bedrooms and adjacent would be my suggestion) then use I3's where people aren't likely to be sleeping or similar, and just omit the tandem ring trigger from the panel.

Thanks, Del, much appreciated.

Just to close this thread, regarding Zone 16 being faulted even when shorted with an 820 ohm resistor and the jumper on the right:
The zone was configured as a 4 wire type (probably the default). Setting it to 2 wire cleared the fault.
 
RV