What are the recommended power washers makes and models for cleaning wooden 
decks?  Price range could vary up to $400.

Power (or Pressure) washers can be a great help in cleaning decks. However, 
there are a lot of choices out there with varying pressure output, gallons per 
minute, accessory packages and prices. Your first choice is between an electric 
or gasoline-powered machine (or even machines powered from a tractor PTO [power 
take off]). Electric models tend to have lower pressure, flow and lower prices 
(about $100 to 250), but for big jobs they might not have enough power to do 
the job in a reasonable amount of time. You can do tough jobs with a small 
machine but you must use a smaller nozzle and move more slowly. Gasoline 
powered units for home use generally run in the $300 to 600 range. You can 
always try to find machines on the used market or at sale prices for less. 

Cleaning decks is one of those in-between sort of jobs, and your choice of unit 
will depend on how big your deck is, whether you plan to just clean off leaves 
and debris or want to strip the surface for refinishing, and how much you value 
your time. And if you’re an inexperienced pressure washer user, you may want to 
err on the side of less power, because it is quite possible to damage the wood 
of your deck with a high-power unit. Be sure to practice on an inconspicuous 
spot first! Also I would recommend considering a rental unit if you aren’t sure 
what you want, so you can try something out with less investment. Rental units 
are available at most home centers and larger hardware stores.

There are widely varying opinions about what to use. For example, it’s 
interesting to read the discussion at FastFacts.com:

http://www.factsfacts.com/MyHomeRepair/washer.htm

The discussion is based on a question similar to yours, and some respondents 
were quite happy with small electric units, while others insisted that a good 
gasoline-powered unit is a must.

I couldn’t find very many specific product reviews that were very informative. 
One good general discussion of pressure washer characteristics based on 
Craftsman products used primarily for car cleaning can be found at MustangWorld:

http://www.mustangworld.com/ourpics/fcar/pressure.htm

Some anecdotal reviews of Karcher, Powerdevil and Nutool  products can be found 
at dooyoo, a British do-it-yourself  consumer review site:

http://www.dooyoo.co.uk

(Do a product search for “pressure washers.”)

A similar American site, Epinions.com had very little to offer.

On balance, I would recommend that you check what is available locally first. 
Shipping costs for a heavy item like a pressure washer will add substantially 
to the cost of anything shipped from elsewhere. If you have a big deck you 
should probably go with the largest gasoline-powered unit you can find for your 
$400 budget. If you’re stripping for refinishing, you may want to seriously 
consider renting an even more powerful unit since you won’t be doing the job 
again very soon. If your needs are more modest, then by all means go for an 
electric unit—probably the most powerful one you can find; it should  still be 
under $300. Pressure washers are relatively simple devices: a motor and pump 
plus some plumbing and an assortment of nozzles. There don’t seem to be a lot 
of compelling reasons to choose one brand over another. If you plan to keep it 
for a long time, you will want to choose a brand and dealer that you have some 
confidence in for parts and service as well, of course. And by all means ask 
the dealer for recommendations as well given the particular scale of your 
needs. Beyond that, it’s probably safe enough to shop by price. If you find a 
cheaper machine in the pressure range you decide is good enough for your needs, 
go for it!

Search terms:

Pressure washer OR washers
Pressure washer OR washers review OR reviews

Happy washing!

All though drdavid has some very good info on the subject, I would place more 
credence in how to use pressure washers to clean decks than the best brand to 
get the job done.

It's the same adage as hiring a plumber to fix your sink, you don't pay him to 
tighten the fixture to the sink, you pay him to know how far to tighten the 
fixture to your sink.

I build decks for a living 
(Sample) http://www.paatving.com/ebay/deck/deck.asp

I have seen too many people turn there decks into "chia-decks" by blasting away 
the surface only to have it dry to a splintery mess the next day. And that's 
about as useful as having Sergey Brin in the goalie net on your team.(he-he)

One must use great care in the use of pressure washers on decks, and different 
materials for which the deck is made can vary the finished product as well.

My advice is to take your time if this is your first time doing it, and make 
sure to not blast the deck into oblivion for which you can never recover.

Buyer Beware
I purchased the 6.5hp Craftsman pressure washer last October, 2003 to
refinish my deck. Worked great for 10 to 15 hours usage but then bolts
that hold water side of pump sheared off. Took in to local Sears where
I purchased and they repaired under warranty, no problem. Since the
deck was almost finished at the first failure there has not been much
usage on the repaired pump. Today, December 3rd 2004, I used to wash
out carport and again pump failed, this time on the piston side. Back
to the store. This time I'm told the one year warranty is out and the
first pump repair was only warranted for 90 days. Now I'm left with a
pile of junk. Obviously the pump design is faulty. Would not buy this
unit again!!

There is a fairly big difference between the Sears' type of pressure
washers and commercial rated units. As we can see from xcraftsman-ga
bad experience, such models are not designed to withstand the long
hour operation. They are usually made to be used 1-2 hours per week
vs. commercial units that can withstand the workload of 20 to 30 hours
of continuous operation. I have been in pressure washing business for
a few years now, and even though I have not worked on pressure washing
decks (aviation is my specialty), you simply cannot do the job right
with a residential model. You will have to spend more then just $400,
but you won't have problems with pumps, engine, seals etc. The
pressure washing equipment is worth the investment especially if you
plan on using it for other jobs around the house (gutter cleaning,
patio cleaning, car wash, etc.). There is a website that offers tips
on pressure washers and decks cleaning:
http://www.ultimatewasher.com/deck-washing.htm
They also sell equipment and chemicals. I would think gas model is
better option for this type of job just because you are not dependant
on electricity and you can move the pressure washer around the house
quicker. Careful what kind of pressure you are using, if it is too
high you can strip the paint easily. Good luck!

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