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Think Before Relamping a Projector Lamp

Relamping can help you spend less compared to buying a new lamp assembly. For users with a talent for electronics repair, the benefits may outweigh the risk involved. In other situations, relamping can have negative outcomes and could cause you to spend more money and time compared to purchasing a new lamp assembly.

Definition of Relamping

Relamping is the process of fitting a new bulb into an existing projector lamp housing which can be done by either a 3rd party or the end user.

There are two products available on the market for customers who wish to save money by relamping, relamped lamps and bare bulbs. A relamped lamp is an old lamp housing fitted with a new bulb. The process for installing a relamped lamp is the same as for a new projector lamp assembly, plug and play. Installing a bare bulb (do-it-yourself relamping) involves carefully fitting the new bulb into the housing of the old bulb and then plugging the housing into the projector.

There are cases where relamping is required or encouraged by projector manufacturers. For example, Zenith sells new TV lamps fitted into used Zenith housings for several of its DLP projection TV models. Zenith and several other manufacturers charge a fee for buying certain lamps without returning a dead lamp so they can reuse the housing. That fee is called a "core charge," and it varies from a few dollars to over $75. Christie offers relamping instructions and tools to save money on several of their high priced projector lamps.

Still, the relamping that gets the most attention lately refers to putting an off-brand bulb into a name brand housing without endorsement or supervision from the original equipment manufacturer. This is the type of relamping addressed here.

Relamping sounds like the easy inexpensive way to replace a projector lamp, but it is worthwhile to research certain negative details before considering the relamping process to cut costs.

Relamping Caution 1 - Compatibility

This issue is of concern to people who plan to buy a bare projector bulb to install in an existing lamp housing. The wattage and electrical connections have to be the same between the bare bulb and the finished projector lamp.

Companies that sell bare bulbs often provide cross references to say which bulb fits each projector. After reviewing several vendor cross reference sheets, it is clear that some companies copy from one another verbatim and some use other sources. The projector lamp cross references do not have the look and feel of information that is adapted by many people from one source.

For my part, I am unable to find cross reference information published by the bulb manufacturers (usually Philips or Osram) to link bare bulbs to finished projector lamps. I would love to find a cross reference like that!

The copying between bare bulb vendors and certain inconsistencies between documents make it obvious that Information about which bulb is compatible with each projector is not always accurate nor is it published by reliable industry sources. It is like trying to write a high school research paper by copying paragraphs of text off the internet; you never know if the information is accurate or if some uninformed person decided to blog about it and call it factual.

A good example would be part references between Philips/OSRAM bulbs and name brand projector lamps. These references are known to as being unreliable by many experts in the industry.

At times, the bulb will not be fully connected to the lamp assembly, causing the entire lamp to fail. There is no known solution for improperly installed relamped bulbs. There are also no known repair shops for relamped bulbs. Your only recourse would be to send it to the company you purchased from, and lose the time, money and effort you have put into the project thus far.

Relamping Caution 2 - User Error

When purchasing a new bulb to insert into your existing projector lamp housing you will be required to do this yourself. By relamping yourself, you run the risk of damaging the bulb and the lamp housing as well as voiding your projector warranty. If this does occur, you end up spending hundreds on a new bulb that you just broke as well as having to purchase a full replacement lamp as a result.

It is also good to note re-lamped housings are old and have been used time and time again. This wear and tear can cause the connectors to twist together or overlap and could lead to short circuiting the lamp and projector, an obvious and massive electrical hazard. Connectors also become worn down after use and depreciate in quality over time. This can affect the stability of electrical supply resulting in image flickering or possibly permanent damage to the projector.

Relamping Caution 3 - Special Tools

In order to remove the bare bulb, the lamp module has to be taken apart, something which manufacturers have not planned for and therefore not made an easy task.

Usually, relamping requires special tools that most people do not have at their disposal. These tools are used by professionals in a controlled airtight environment. Most projector lamp housings are not designed to allow easy access to the bare bulb and often have to be broken open during replacement.

If the housing has to be broken, it can be difficult to rebuild the plastic (often impossible to get it back to its original condition). This means the lamp module may not fit correctly into the projector and can cause improper focusing as well as a fire risk. Even if the housing remains in good condition, the bulb has to be jigged or lined up perfectly inside the housing and the projector to display properly.

Relamping Caution 4 - Mercury

Besides the issues involved in purchasing and installing a lamp there are potential health issues involved with relamping. Projector lamps contain mercury which is very poisonous. Here are the Environmental Protection Agency (EPA) guidelines for cleaning up a mercury spill.

There is a risk of damaging the old bulb while removing it from the housing. If the bulb cracks or breaks, mercury may leak out. The risk of spilling mercury from the bulb can cause serious health problems to those who come in contact with it. Proper disposal of mercury is also very important for your health and for the safety of anyone who comes in contact with the discharged lamp.

Relamping Caution 5 - Normal Wear and Tear

Dust particles can build up around the bulb and module over a long period of time when reusing the same lamp housing over and over again. These dust particles are difficult to remove completely, even if you are an experienced engineer.

The dust particles retain extra heat within the housing as well as disrupting airflow that cools the lamp. Both of these elements shorten lamp life and can cause the projector to overheat or malfunction. A fire hazard can result.

Projector Lamp Center recommends cleaning out the projector and housing with canned air from time to time limit dust build up.

Relamping Caution 6 - No Tech Support

Also, what if you have the lamp connected incorrectly once relamped and you just can't figure out why it isn't working? You can't call a lamp repair man to come by and check it out; there is no such thing.

You cannot ask your father because he most likely doesn't know anything about a projector lamp. Doing things such as relamping can be quite a gamble that you have to decide if it's worth it to try. We would recommend sparing yourself the trouble and chance of failure with relamping by purchasing a brand new lamp, trouble free, and guaranteed to be satisfactory.