Maxim M250 Not Providing Enough Heat

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.

faxhb

New Member
Jan 6, 2013
6
I have been using my Maxim M250 for just over a month now. It works great and I do feel the heat when the temperature outside is around 25 degrees or higher. The problem is when the temps dip below 20 degrees, which does happen every few weeks or so. When that happens, I just don't feel the heat in the house even though I have installed brand new windows, the thermostat claims the temperature inside the house is 68 degrees or so, and the water temperature on the Maxim says 190F. What am I doing wrong? Is it the house? the Maxim? or what?
 
What is the return water temp? If it is still hot, perhaps the house has inadequate radiation installed?
 
The temperature of the water returning to the boiler from the house.
 
I didn't know there was water returning to the boiler from the house. How do I check that? The Maxim does not heat my water. I use it only to provide for central heating.
 
If your boiler is putting 190 out you must be losing it either in your pex or perhaps your heat exchanger isn't functioning. Or perhaps you're not pumping properly? What kind of pump are you running? What do you use in the house to move the heat? Forced air furnace with an HX coil in the plenum? Where the pipe comes into the house how hot is the pipe? If uninsulated it should be too hot to touch.
 
Additionally, I did not have this problem when i was using oil last year. I switched to wood pellets to save money on oil, but with oil heat, I would simply turn up the thermostat and would feel plenty of heat. Just thinking that maybe the problem is not lack of insulation.
 
We need more details about the installation. stee6043 asked some good questions. In these details, include the length of the runs to/from the house to the boiler, the depth they are buried, and how they are insulated. Then describe how the system is connected to the home oil system.

Also, was this a dealer installed or self-installed system?
 
It is forced hot air with a coil. The pipes are not insulated and they are hot to the touch but I probably can touch them and hold on to them for a minute or so before they start burning me.
 
Sounds like there may be some serious heat loss. The pipes definitely should be insulated. How far away is the boiler from the house? How deeply buried are the pipes?

Do you have the specs on the coil? What is the output btu of the furnace?
 
These are all good questions but frankly I can't answer them intelligently. They are just beyond the scope of my knowledge. What I do know is the following: 1) it was a dealer install; 2) the pipes are not insulated; 3) the boiler is about five feet away from the house; 4)according to the booklet that came with the furnace, it has a 250,000 btu rating.
 
5' from your house and this was dealer installed? Oiy. Do the pipes go underground to get into your house? Can you find the pump and is it running?
 
It is forced hot air with a coil. The pipes are not insulated and they are hot to the touch but I probably can touch them and hold on to them for a minute or so before they start burning me.


Let's start with a couple basics.

I assume the un-insulated pipes you are speaking of are the ones inside your basement. Correct?

If so, it would be really helpful if you could get your hands on a thermometer of some kind that would measure the temperature of both of the pipes where they come in the basement. Get a piece of foam pipe insulation wrapped around the pipe and slide a cooking thermometer between it and the pipe if nothing else. Note......if those pipes are actually 190* you will not be able to grab them for even a couple seconds without burning your hand.......with pex maybe a little longer, but certainly not copper.

Next thing I'd like to know is the dimensions of the coil in your furnace plenum. If you can, get a tape measure and see what the size of the coil is. Just the outside dimensions will do and from there we'll have to assume a few things for now. We need to know if it's 16" x 20" or something closer to 14" x 16" or whatever. From that we can get an idea what you are supposed to be getting for output from the system.
 
Pictures might help.

So is this a new installation?

If so, I would get the installer back out there to get things working right - you should be having all kinds of heat from a 250,000 btu boiler. Something is out of whack here - he SHOULD know or be able to figure out what the problem is and be able to fix it at no cost to you if its a new install.
 
Something is not right in the house or lines if at 190 water u have no heat. Got pictures or a diagram.

Bypass open around house coil?

Tim
 
I agree with everyone else here - you should get the installer back and have him fix it. A unit that size should make ample heat for even a *large* house. I have an M175 on an 1800sqft 1940's house with *very* poor insulation (you can feel cold air blow in around some of the doors/windows), it makes plenty of heat for my hose even with the feed rates turned all the way down. On the coldest days (15 degrees f), it bounces between "normal" and "high", but the rest of the time it's about 70% "normal" and 30% "idle" (with the feed rates on all three at the minimums). If the feeds were higher, even the M175 could heat a leaky house twice the size of mine. Your M250 should provide *tons* of heat. Call your dealer and complain - he probably botched the install somehow.
 
Status
Not open for further replies.