Monitor MZ20-40C air fan filled with water condensation

CRae

We have a monitor MZ boiler -- it's been a monster problem for us since installed 8 years ago.  Our newest problem today is the air fan sounds like it's broke.  We figured out that the overflow cup is full of water from excess condensation.  Also the vent pipe evidently was installed wrong and is angling downward towards the boiler --rather than declining towards outside.  Anyways -- how do we get the water out of the air fan.  We angled the vent pipe down towards the outside of the house and water poured out of it.  We also removed the overflow cup so water can easily drain.  Should we just keep it running so that it dries itself out?  PLease help! 

BTW -- if you have any other contests on ugly install -- I'm thinking we can win one with this botched $25,000 mess we have. 

CRae

oh -- also

I forgot to mention -- the air fan makes a HORRIBLE sound running (I'm guess it's the water rumbling around in there -- and only one burner (we have 2 burners) will light on and off.  But it won't stay lit.

Brad White

The MZ

fan intake draws from the upper RH side of the cabinet and draws the air from the cabinet volume. Also the exhaust exits the exchanger out the bottom and rises to exit the cabinet at the upper left - my bad!.



I am at a loss to figure out how you are getting water inside the fan housing. The only source I can envision is condensation of room air leaking to inside the cabinet and even that is a stretch.



Can you post a picture or two?

CRae

photos

Thanks for your help!  I will post photos in a few minutes.

CRae

photos

The noise is definitely coming from the heating fan (upper left side of unit).OOPS -- It's the upper RIGHT SIDE (not left side).

CRae

photos

OOPS!  I meant the fan is on the upper RIGHT side.

We just took it off and like you said there is no water in it.  What else could it be?Is the fan bad?

Brad White

I messed up too

with the right and left thing



Anyway, the fan wheel should spin quite freely with very little effort and spin by hand for some time after pulling your hand away or after the system is "bumped" to start the fan, then stopped before it fires. The fan should spin after a short bump for at least half a minute to a minute by my experience.



If there is any grating or wobbling or it stops in a few seconds, yes, the fan would be bad and need replacement. I had heard that the MZ was discontinued. If confirmed, I am not sure what support is out there.



I had an MZ also, single stage. Worked OK, condensed well, but without modulation it was no more efficient than my former Burnham Series 2 (#204) with a 4-way mixing valve. In fact my gas bills went up slightly on a normalize degree-day basis. You at least have two stages.



Let's hope you can get a new fan. The company that makes the fans as an OEM product may be able to get you a replacement if the Monitor factory cannot. I believe the fan is made by EBM Pabst in Germany.

CRae_

MZ Fan

Thanks for the time to help and post! I appreciate it!



That just figures -- that MZ is no longer.   Like I said we've had nothing but problems (mostly from poor installations from the beginning). 

I think you are correct about the efficiency factor  -- we haven't noticed a savings.  Like you said the dual burner helps, but compared in our old boiler.... we haven't seen a significant improvement with fuel efficiency.



We just called someone to come out and take look -- sounds like they might have trouble getting the part.   I'll let them know the info you gave me on the mfg, if they need it.

Thanks again!



(ps: i had to create another account, since I couldn't get logged in with my other one - that's why my user name is different).

Alan (California Radiant) Forbes

MPI

It seems as though I spoke to someone at the company not long ago.  Try this number:



(800)524-1102



I installed 6 of them in 2000 and all of them are still working.  They come with a bottle of conditioner to add to the heating liquid and they won't warranty their boiler unless you have used it. 



I've had a few problems with them - clogged strainer that wouldn't allow the flow switch to make, leaking auto air vent, failed pump, etc., but nothing major like a bad fan.  It sounds as though it was damaged somewhere along the way, like something hard was sucked in or fell in.  Those fans are well built.

CRae

mz

Thatnks for the info!  I gave the phone number to our heating guy and he called and ordered parts today. 

It was the combustion blower/inducer and an ignition switch type part.

Sounds like it'll be around $1,000 to fix.  "assuming" that's all that needs replacement. 

CRae

warranty?

Alan,

Also -- do you think this would be covered under warranty?  our system was installed in 2003 and it has the conditioner in it that they require for warranty repairs..I'm just not sure how long they warranty their systems and what parts.

thanks again!

Alan (California Radiant) Forbes

Warranty

I would think their heat exchanger would have the longest warranty.  Everything else is probably 1 year.



It wouldn't hurt to ask, though.