Ademco 20P alarm systems for the do-it-yourself homeowner

Over a decade ago, I finally bought an alarm system, mainly because I realized I could not hear the basement alarm when I was upstairs; and because a gang of criminals was breaking into house after house, apparently with no end in sight (they were eventually caught by the police). I don't have any valuable valuables, but it’s a pain to replace things.

Installing and adapting the Ademco 20P alarm system is somewhat painful, given some of the oddities involved; and buying the gear yielded wildly variable prices. Why should you have to waste time like I did, when you can just read this page?

I am not a professional installer. None of the advice or information in this page should be taken as being professional level advice. I might be wrong about particular things, or outdated; this is especially true regarding alert services and the dialers. You must proceed at your own risk from here.

Choosing the Ademco Vista alarm system

There are a few good sources of information on alarms. There were forums, some of which are long-dead now, but it’s nearly impossible to find a comparative review that fits your needs.

Eventually, I went with one of the industry-standard alarms mainly because it was an industry standard. This is, as you guessed, the Honeywell Ademco Vista 20P; the Vista 10P and 15P were similar, but less expandable and around the same price. Ademco’s basic design is ancient (it looks like it’s from the mid-1970s), though updated over the years; and in recent years, upgrades have included cell service, USB connections, and smartphone support. In 2022, the 20P is still sold and pretends to be current.

I would probably select a DSC system if I was doing it again, because they are “supposed” to be easier to work with, and the accessories are cheaper. Ademco (Honeywell) does not support do-it-yourselfers or homeowners directly, and barely supports the pros. Indeed, it seems likely that Honeywell and its spinoff Resideo deliberately obfuscate so that people will buy from professionals.

Intaller vs DIY (self-install)

Installers’ prices ranged from “free” plus three years of monitoring at $30/month, from ADT and Brinks, for a very basic system; to $3,000 plus the same monitoring, from local installers, for a better system.

The proposed system was relatively small, with three smoke alarms, two doors, and one motion sensor (for far less than any of the quotes, I later added cellular, three more smokes, some windows, a couple of glassbreaks, and more motion sensors and audible alarms).

For a smaller system and a person who doesn't want to deal with the installation, have them do the hard work, use their service for the contractual three years (total: around $360), and then take over the system, getting the installer code from them or via other means; you can use a cheaper service (monitoring starts at around $10/month with the same response time). A professional may also be a better option if you can get one who will work for less.

The Vista 20P is used by many major chains, including ADT, so forums are full of information about converting old systems.

Most of the self-install help forums have disappeared now, purchased by alarm monitoring companies and installation providers—the content taken offline.

Buying the Honeywell Ademco 20P system itself

You can buy stuff cheaply on eBay, but it's often just as cheap to go through an established store with strong customer support and fewer sellers who leave out key parts or sell obviously used parts as “new” or “refurbished.” Needless to say, you don't need to buy accessories from the same place.

The cost of the kits varies according to what’s in it. You will need a 6160 keypad (preferably the 6160RF to communicate with wireless devices) to program the system, unless you get access in some other way (and you might need the 6160 anyway to set that up). I'd recommend you have at least two keypads (the touch-screens may not add anything you want beyond the old fashioned ones); the (fairly quiet) indoor siren; the power adapter (transformer); and small backup battery (though you will probably want a bigger one later). If the kit comes with sensors, they may be sold at a discount; check it out. Oh, and you will need the metal cabinet it all mounts in.

To install everything, you will also need a teeny slot screwdriver and a larger slot screwdriver.

Later, you may want a bigger backup battery and additional power supply (if you add a good deal of wired items that use power, e.g. sirens). A modest system works fine with the little transformer. Other items require more.

Don’t expect outside help with programming. You get the manual; it's not too hard to use, but you may want to copy some pages so you're not always riffing back and forth. Record those codes as you add them!

Adding sensors

Note that the term “Honeywell Ademco System Sensor”  means that the device is made by System Sensor; it's not an Ademco part, but it is compatible with your system in most cases. You may need to buy expensive adapters. The equipment seems good but not always compatible; caveat emptor.

For wired smoke alarms, I went with GE two-wire models. For wireless smokes, I chose System Sensor. Ademco didn't seem to have anything wireless that was suitable. One of the GEs died young; they’re now sold by United Technologies as Interlogix, and United Technologies does not provide end-user support, so it's probably better to avoid them.

NuTech makes a USB adapter, but the last time I looked, it was only a curiosity for technogeeks. You need to program it and such. More recently, more extensive add-ons were created for smartphone control.

You should probably get a waterproof strobe/siren to mount outside; they are cheap and tell people where to look for the siren noise. The last time I looked, the wireless ones were overly expensive, but if you aren't running the wire yourself, they're probably cheaper than hiring someone else. If you come up against a really sophisticated crook, though, a subtly mounted unit with wires may prove better than a wireless one; wireless signals can be jammed.

The keypads

There are many newer keypads now, using newer technologies such as touch-screens. However, all you really need is the 6160RF, which both lets you program the system and run wireless accessories. The wireless keypad is nice if you may be moving it from room to room, or don’t want to run four thin wires upstairs, but it's just a remote. The 6150 is inexpensive but really just a keypad, it doesn't give much information and can't program the system. A side note on the wireless keypad: the pad itself is over $80, but it comes without a DC adapter, which is over $20 more (or you can use a generic one).

The keypads require four wires; fortunately there is four-conductor wire. The company suggests using 18-gauge single-stranded wire. Investing a little more in high quality wire is worthwhile since this will likely be run behind walls and any failures can wake you up at 2 am. Speaker wire is too thick for keypads but works for sensors. Using the correct colors makes it easier, but isn’t required. Wire up as much as you can before connecting the power and battery; the 6160 keyboard must certainly be wired up before you start.

I will suggest that you take the first four wiring points (screws) and run single wires from them to wiring multipliers, so you can add more devices more easily. I ran four devices off those first four points, and it was hard to get a reliable connection going. For the other two-wire things, like smoke and door alarms, you can use thicker wires and put those little fork connectors on the end instead of connecting the wire directly underneath the screws.

Programming the Vista 20P

First, it's time to do terminology: zones and loops.

Zones are two terminals on the alarm board—or a place in the wireless system memory.

Loops are basically functions done by the devices. A typical smoke detector, for example, has a “smoke alarm” loop and a “tamper detection” loop which sets off the alarm if the battery cover is opened. Window/door sensors usually have just one loop; some have two loops, but you’re only supposed to use one. Smoke alarms may have three loops—for smoke-and-fire, for maintenance (low battery or replace sensor), and for freezing temperature. You can choose whether to listen to these loops or not.

If it helps, think of loops as being circuits from the system to the device and back (a wire loop) gathering specific information as it goes.

Wireless programming has some tricks. First, read the instructions (obviously) and find out which loop to use; then use the keypad to enter programming mode (4112800 if you have not yet changed the installer code), *56 to get into device programming, then enter it according to the step by step instructions. As I wrote before, you may need to enter more than one “loop”  for each zone. Each new loop for a wireless thing goes into its own zone.

At some point, you need to provide the serial number for the wireless gizmo. The instructions usually say to bring the gizmo to the control box, but (a) any devices that are too far away or blocked for whatever reason will be registered without you knowing there's a problem, and (b) there are sometimes problems if you do this too close to the alarm system brain. (Thanks to the old DIYalarmForum’s Airdorn, mjohnson, Alarmtech, and DEL Installations!)

When the system asks you for the serial number, there's an odd setup for smoke alarms and glassbreaks. First, open and close the alarm (with the battery installed!), setting off the tamper sensor. Then make sure you set the loop to 1; the default is to pre-fill the loop as 4, which is the tamper alarm.

The setup for door/window and motion sensors is the same: install them (with the covers fully closed) and, when asked for the serial number, set them off. Make sure you open the door or window widely or really dance around to set off the motion detector; some of these have a pretty wide range of allowed motion. Don't press the tamper alarms on these.

The only time you really need to worry about running out of zones is if you plan to have a lot of windows and doors on their own zones, along with multiple wired smokes. There's a definite limit to wired zones, though you can buy more. Wireless zones are less likely to be a problem.

Wired programming is simpler, since there’s just one zone and no need to establish serial numbers. Use just zone 1 for two-wire smoke-fire sensors; four-wire detectors can use more than one zone, but then you have to add a relay.

When the alarm bell rings

The Ademco Vista 20P has a telephone connection, as well as a cellular adapter, but both are to be used only for monitoring services unless you buy a cellphone add-on. AlarmSystemStore sells an inexpensive monitoring setup— $107/year for the basic telephone ($9/month). They also have a cell/Internet add-on for $150, including one year of service. Their monitoring is UL listed.

Internet services from the same provider (here I should mention, though you have no reason to believe me, that I am not actually connected with them in any way, got nothing free from them, etc.; but of my original list of providers, they are the only one still alive!) include:

Another provider, AlarmRelay, is also UL certified, and provides similar services; landline monitoring is $9/month, Internet monitoring with remote control is $14/month, and cellular monitoring is $20/month. They are not by any means the only discount monitoring services. What’s more, you can keep theirs and also have the auto-dialer (or a cellular version, or an digital ITTT version) if you want.

I’d recommend you wait to get monitoring until a few months after you get the alarm, when you know you won't be setting it off by accident any more! The first week will probably include numerous false alarms.

You can also set up your own auto-dial system to call your cell and maybe the neighbors when something happens. My own system had a United Security AD-2000 for around six years; I couldn't figure out the “right way”  to do it and just attached it to the alarm bell (another set of connections you may want to add easier “add-a-wire” devices to). When the alarm activates its siren, the AD-2000 calls people until someone tells it to stop. It keeps going after the alarm is cancelled.

You can get cheaper auto-dialers, but if you successfully figure out the instructions and have the right relay, the AD-2000 can send specific messages to specific phone numbers. In many towns you need a permit to auto-dial the police, by the way, but this would be a nice setup so when you get a call, you know whether it's a fire, break-in, or cat wandering in your office.

Finally, just remember to put the system into test mode and check all your smoke alarms with artificial smoke, and test all your motion detectors, at least once every quarter. You may need to call your monitoring service first! Indeed, they can help you to do this.

That’s it for now. More to come...

Books by David Zatz