Change an old 15P to a new 20P Question

[HDE]

I have an old Vista 15P (PROM Rev 3.1) and I plan to add 2 - 4219 zone expanders and then rewire to change my zones to fewer sensors per zone. I am also planning to upgrade the PROM to Rev 10.24.

Since I am rewiring and then reprogramming would it be a good idea to change the old 15P to a new 20P?

[Static]

Spidey senses are tingling. I have a strange feeling the 15P only supports one 4219 HW expander. I'm rusty and could be wrong, check the specs or maybe someone can confirm? If it does support only one and you want two then yes, a 20P would be a good upgrade.

[Magnum Alert]

errrrrrr.    48 expansion zones on the 20P, I think only 32 expansion zones on the 15P.

I *think* it's the 10P that can only have one expander.  Or perhaps it's the 10 that can have _only_ wireless expansion.  I used to have all that in my dropbox for quick reference, but it got hacked.

[ChosunOne]

The 15P has 6 on-board zones and supports up to 16 expansion zones. "Expansion zones" means either hardwired (4219) or wireless (5881) expanders, or both. So yes, it can support two 4219 HW expanders.

So a total of 22 zones, _including_ the on-board hardwire zones.

Magnum Alert, you may have been thinking of the old 20SE, I seem to recall that supported 32 zones total.

[Flyct]

For less than $50 you could buy a new 20P and zone double it. No additional hardware needed. The kit come with zone doubling resistors.  Zone doubling will give you ability to wire 15 hard wired zones. All zones but zone 1 can be doubled.

I did that on a previous Home and it was very reliable.