This topic covers issues with older Davis stations, primarily original Vantage Pro (what are now referred to as VP1 stations to distinguish them from the current VP2 models) and the prior generation of Weather Monitor II and Weather Wizard III stations. There is also a note on the initial VP2 stations of 2004 and 2005 vintage.
All of these models are likely to be at least ten years old now and so relatively few will be in active operation still. So here are just a few notes on these older stations, covered in the subheads below:
Initial VP2 models (2004 and 2005 manufacture)
The VP2 model was first released in late 2004 and was subject to an important revision in 2006 when digital T/H sensors were introduced (and certain console hardware changes were made). The main VP2 T/H topic has details about the specification and replacement of the digital T/H sensors.
But digital T/H sensors cannot be used on most pre-2006 VP2 models (identifiable bythe Mfg Code starting A4 or A5), which were fitted with the older analogue T/H sensor assemblies. Davis do have a policy of maintaining a supply of spare parts for at least 5 years after a part/model is superseded and this policy was certainly adhered to for the analogue sensors. But the supply of these sensors eventually became completely exhausted and no new parts could be manufactured. So regrettably anyone with a VP2 station of 2004/5 vintage will be unable to source a new sensor (other than eg from eBay). The only answer is to buy a complete new SIM board and modern digital T/H sensor, which will of course be mutually compatible. This isn’t necessarily the wisest course of action since the cost of SIM board plus T/H sensor is significant. It is arguably more cost-effective to buy a complete new ISS rather than to fit new parts to an ISS which is 11-12 years old and which will almost certainly have other components approaching the end of their service life.
Note: Some VP2 systems produced towards the end of 2005 are in fact compatible with digital T/H sensors, despite the official changeover date being 1/1/2006. Apparently these can be identified by a small round sticker on one of the SIM board chips bearing a hand-written ‘v1.6’ – probably denoting the ISS firmware revision.
Compatibility of VP1 and VP2 models
VP1 and VP2 stations use a significantly different data protocol from each other to communicate between sensor transmitter (ISS) and console and as a result it is not possible to intermix VP1 and VP2 consoles and sensor transmitters. In other words you cannot use a VP1 console with a VP2 ISS or vice versa. This is true of both cabled and wireless models (because the cabled models still used a similar data protocol to the wireless models).
Weatherlink data loggers originally bought for a VP1 station cannot be used with a new VP2 station. This is not related to VP1/VP2 differences, but to the fact that VP2 stations manufactured since early 2013 require a logger with an updated specification – see the logger compatibility topic for further details.(VP1 loggers can be used successfully with pre-2013 VP2 consoles, but this situation typically won’t be relevant to VP1 users looking to upgrade to a new VP2 station). However, new Weatherlink loggers can be used with a VP1 station without problems. NB Data loggers for the older Weather Monitor II and Wizard III stations were of a completely different design and cannot be used with either VP1 or VP2 stations.
New parts for VP1 and older stations
Brand new mains station components (eg console and ISS units) are simply no longer available from dealers – in the main, stocks were exhausted several years ago, although it may still be worth asking a larger and well-established dealer because they may still have the odd component as part of their residual stock. Occasionally components may still turn up on eBay and similar sites, but will typically be in used condition and therefore of unknown reliability. Some replacement spare parts and repairs to units may still be available – see below for details.
Replacement sensors for VP1 and older stations
The one sensor that you’ll find it virtually impossible to source new now is the temperature/humidity sensor for VP1 and older stations. (VP1 and WMII parts were distinct parts but share the problem of unavailability.) Manufacture of these parts ended several years ago and stocks at Davis and at dealers have long since been exhausted. Note that it is still possible to replace the temp/hum sensor with a simple temperature sensor, which is still available – obviously the humidity and dew point readings will be lost, but it may be a way of prolonging the life of an elderly system.
Other standard sensors (except for the pressure sensor, which is on the console main board) are still readily available. The 6410 VP2 anemometer is fully compatible with VP1 and older stations. A defective rain gauge can be repaired either by replacing the reed switch or by substituting a separate 7852 standalone rain gauge (or its new equivalent, the 7857 pole-mounting rain gauge). And the VP2 6450 solar and 6490UV sensors are both fully compatible with the VP1 station.
Replacement transmitter parts for VP1 and older stations
Replacement transmitter boards may still be available in principle, but they will be relatively costly and dealers may be reluctant to source them in practice. Few dealers will maintain stocks nowadays because of absolutely minimal demand and sourcing a replacement board up the supply chain may be a long and fraught process.
Console repairs for VP1 and older stations
The situation here is similar to that for replacement transmitter parts – it’s not impossible that parts may be available or that repairs could be done, but the uncertainty and cost and time taken in sourcing parts might make attempting the repair seriously unattractive. If such a repair is needed then the likely conclusion is that the station is beyond practical or economic repair.