Good idea; Bad design

I bought the HWM 330 because it advertised stainless steel heating and the pictures on www.iallergy.com look pretty cool.

When I got the unit, before I filled the tank, I was still quite satisfied with my purchase - the stainless steel heater looked pretty impressive and the unit does look cool just like the pictures.

Re-filling
However, when I took the tank to the sink to fill with water, I was not at all impressed. The water tank is big but that's not the problem. Water tanks for warm mist humidifiers (the ones I have used) have openning on the bottom. So when you refill, you have to turn it up side down. The water tank of the last humidifier I owned (also from Honeywell, don't remember the model number, it ran fine, but I ruined it, long story...) had handles on top and bottom, which comes very "handy" when you turn the tank upside down.

However, the water tank for HWM 330 only has one handle on top, which creates many challenges:
1. It is awkward to turn the unit upside down since you don't have any handle on the bottom (or the new top);
2. when you are refilling, you need to rest the tank on the bottom of the sink and support it on the sides, and this is made even more difficult because of the "cool" look of the unit - the top, now the bottom, as you refill, is shaped at an angle. You really have to hold on to the tank when it is refilling to balance it.
3. when you are done refilling, it is even more challenging: you need to twist on the cap (more about the cap later) and turn it upside up before transporting. Well, because there is no handle on the openning end, and due to the size of the tank, you need to reach down to the bottom to grab the handle. Again, because the handle is made to look "cool", it almost flushes with the bottom of the sink and it is difficult to grab from down there.

OK, let's assume you overcome the above challenges and manage to turn it upside down, fill the tank and turn it right side up and you are thinking that you are now ready to transport the tank to the unit. Just one not-so-tiny problem, the tank is leaking! You turn back to the sink before you flood your hallway. You turn it upside down again, twist open the cap and try to twist it back on. You realize what the problem is: the cap is almost 5 inches in diameter (which some say is a plus because you can reach in to wipe the tank clean) and one inch deep, so when you try to twist it close, besides straining your hand to get a grip, you can just see that it is not very likely to twist tight. Now you are more careful: you twist it close, turn it right side up and test it over the sink first. Except that you need to do this a few times until it closes and it does not leak before you feel safe to transport the tank to the unit. You are now exhausted (you need to refill about every other day.)

Operation
Once you fill the tank and fit it onto the unit and turn it on, it does produce steam almost instantaneously (in comparison, the other humidifiers I have owned give out steam in about 3-4 seconds, which makes no difference.) It does what it is supposed to - humidifies the room quite efficiently especially if you use the faster speed.

With a full tank, it runs for 24 hours on low speed and about 10 hours on high speed.

It has a thermostat though I didn't get to use it.

The unit auto shuts off when it is out of water or the room reaches the desired humidity level.


Cleaning:
Just like the last humidifier I owned, the manual recommends weekly cleaning, which is a 2-step process: scale removal and disinfecting. The preparation steps before cleaning instructs you to:
- turn off the unit
- remove the water tank
- remove the power unit
- remove the water tray* (note this step)
- and so on.

Then the instruction for "scale removal" tells you to
- fill the removable water tray with white vinegar *

* The problem here is that the removable water tray is not exactly a "tray" it is really an upside down funnel, so you can't really "fill" it with liquid.

The instruction also later tells you to (as part of the disinfecting steps)
- fill the water tank with dilluted bleach solution and
pour some of this solution into* the removable tray.

Again, you can't fill liquid "into" a funnel.

Oh, the one thing that got me into buying this unit is the "Stainless Steel Heater". I admit, again, it looks pretty cool, shiny and clean. And there are these "mineral absorption pad" that you place over the heating plate that is supposed to absorb minerals from the water and replace the pad regularly. The first time I replaced the pad, some of the materials got stuck on the stainless steel plate so the plate does not look shiny anymore, just after a few weeks. I imagine this is probably not going to be a huge problem if I do get to the point of cleaning the heating plate.

But I won't, for a while, because I just bought another humidifier - one with handles on the top and bottom - and I am pretty happy with it so far. Will report back on that later.