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Windows all have condensation on them upstairs and downstairs during winter months only. Running a portable dehumidifier helps a bit but doesn’t solve the problem. Never had this problem until the furnace was replaced. We do not have an air exchanger. This only happens in the winter (we do have central air). Does anyone know why this happens and will installing an air exchanger fix the issue? Any suggestions, advice or comments are appreciated!

IDK about the air exchanger, but if you recently changed your furnance, high-effeciency furnances tend to not dry out the ambient air as much as older furnances. That's probably why you're noticing it now. With A/C you won't notice it because of the different temperature differential, but also because A/C by it's very nature draws moisture from the air (that's how it cools).  
 
Also, if you have older windows, they won't have the same insulating/R values as newer ones. If your windows are due for replacement you might want to consider that as well. In the meanwhile, there is a plastic film you can apply for the winter months that will provide extra insulation and reduce the condensation. It will also reduce drafts etc and keep your house warmer.

We had the same issue the first winter with new energy efficient furnace. Our furnace man drilled another opening in the basement wall to get more air into the house. We could adjust the amount of air coming in with an in-pipe damper. Worked great! In subsequent winters, for whatever reason, we haven't had to open up the extra air inlet. And no more windows with condensation.

It will help a lot, if properly installed and maintained. It is a good way to control your air quality in the house. Often you can get the air too dry with an HRV, causing itchy skin. The colder it is outside, the drier your indoor air needs to be in order to prevent condensation on the windows. The ideal humidity level is not the same for your skin, your furniture and your windows. An HRV gives you the best chance of finding that medium ground. Depending on your house, they can be pricey but it’s worth it. The bonus is less chance for mould and it takes a lot less energy to heat dry air as opposed to highly humid air.

When was the last time you looked at all of the exterior vents? Dryer, bathroom and the kitchen hood... they could be causing the issues, now that you've replaced the furnace. Going off of the same idea as the OP and the others, the new high efficiency furnace is not drying out the house as before or maybe the fan isn't moving enough air where it's needed most. Yes, an exchanger might resolve some of this by pulling out the moisture. However, I would check a few things first... Just in case. The older furnace may have prevented the OP form noticing that the dryer vent isn't doing it job properly. Take a peek to see if it's still hooked up and sealed with the "shinny tape" meant for HVAC lines. Clean the bathroom exhaust grills, throw the range hood screens through the dishwasher, look at the fan blades to see if they are clear of stuff and go outside to see if the flaps open all the way when those fans are running. That process could result in being the cheapest fix. Another problem could be an underpowered furnace fan. Are the bedrooms now feeling warmer in the summer and cooler in the winter or it seems to take a lot more time for the temperature to adjust in rooms with the furthest vents? Perhaps there's not enough air blowing there. If the air isn't moving as much in those rooms, condensation will eventually build up (especially on older windows with poor R value). I have an sixty year-old house with four inch ducts leading to our second floor. Everything was fine with the mid efficient furnace we had before. But when it failed, we went to the high efficient version with a variable blower fan and our windows got condensation and ice throughout the winter. We tried to run the exhaust fans longer and that helped a bit. The "furnace guy" said that the exchanger will help a bit more, but it's still the fact that most new furnaces are not engineered to run through anything less than five inch duct lines. Especially all the way up to a second floor with minimal air returns. Our solution was to install ceiling fans in the upstairs bedrooms and replace the exhaust fans in the bathrooms during their renovations with the highest CFMs that were available. The same was done with the range hood with a unit that was rated well for high volume air movement. Now, there's little moisture on the windows and only when if the blinds are down for an extended period of time. ...And we never had to install an air exchanger. If you do have four inch ducting, another solution could be to install "booster fans" into the ducts leading to the problem areas. I haven't had to do that, but I'm tempted. However if you do, have someone who has the knowledge to insert and wire in those fans.  
 
Just my opinion, I could be wrong.

There was one winter when our air exchange was broken, and boy did I notice the difference! I would recommend getting one. Like you say, it doesn’t matter during the summer, but it’s far better in winter.

Before you go out and spend lots of money try just running your furnace fan all the time.  
Set it to "ON" not Auto. Having the air moving all the time may help.  
If not then try what the above poster said about ceiling fans or just running small fans on your windows.  
Also don't close your curtains all the way. Leave a little around the edges or the bottom to help get the air flowing but them.  
 
Good luck

Just another suggestion for the OP.  
Make sure you clean out all of your air intakes and check furnace filters also. I had the same issue happen in our place recently, and discovered that the air intakes were plugged up on the outside of the house.  
You should also check for washable filters. My furnace has a washable filter instead of the cardboard filter throwaways. Also, if anyone does have an air exchanger, the same thing applies. Check all filters, and wash or change them out as needed. If the air coming in, is restricted in any way (aside from normal filtration), the system won’t be functioning properly, therefore possibly causing excess humidity to build up in the house.

Thank you for the suggestions, advice and comments. We have checked the outside intake and it’s clear. Checked all the interior intakes and they were a bit dusty but not blocked so we cleaned the dust out. We turned on the ceiling fans and also run the furnace in the ‘ON’ position. Do you run it in the ON position non stop all winter? We also periodically open a window to let the dry cold air in. All have helped more but doesn’t get rid of the problem completely. A bit more info, it seems to happen mostly overnight and slowly goes away during the day, then comes back at night. The bedrooms furthest away from fans and north facing don’t seem to ever completely rid of the condensation even with a portable fan going. It’s not the whole windows that has condensation, just about 2-4 inches in the morning at most. If we can’t get things more under control, will have to take the advice of some and look at further solutions.

When we built our house we had about two years of high humidity, and that was with an air exchanger, takes a long time to get the moisture out of a new house.  
In my complaining about the moisture mostly along the bottom of windows, it was suggested to me to buy some 1 1/2 inch blue styrofoam insulation, then cut it in strips around 6 inches wide and place on the outside of the windows at the bottom of the glass.  
Now maybe this looks different, but it allows the glass at the bottom, on the inside, to be warmer, resulting in the moisture that collects at the bottom to evaporate.  
If you wanted to try it on one of your bedroom windows, it could let you see the results without costing much money.  
Just a suggestion, and it worked for us.

Leave it in the "ON" position all winter! It will help keep all the levels of your house the same temperature as well as keep the air moving in your house!  
It does take some time to get all the moisture out of your home so be patient.  
Wipe the moisture off the windows in the morning and open up all curtains and window coverings.  
There is little to no added cost for running your furnace fan all the time with the new high efficiency furnaces now a days compared to the start ups that the motors take.  
The insulation on the outside of the windows is also a good idea.

my wife and family just bought a 1966 house in the country had a plumber electrician put all new ductwork rip out baseboard heaters  
and install new electric furnace and A/C which havent use yet but furnace blower is going is set to on lots condensation on widows but we are sure we have to up date the windows to as they are 1980s windows do i still put that blue strip around outside like one of yous said and where do you buy this stuff this has been an informative topic  
thanks for suggestions

One thing as a suggestion after reading this thread, as there were several references to having additional fresh air intake, not through a HRV unit.  
 
The idea of a fresh air intake only works if your house is in a negative pressure state. Think of your house as a sealed envelope: it is capable of holding only a finite amount of air. So running your furnace fan, while good for air movement and circulation, will not bring fresh air in as the house envelope is "full". There has to be an exhausting of air to allow the fresh air to come in, so by turning on an exhaust fan - bathroom or kitchen - you are forcing air out of the envelope and making room, so to speak, for the fresh air to come in. With the new high-efficient furnaces, the same principle applies as they are drawing the combustion air directly from the outside and not using inside air for that process.  
 
Hope this helps.

I used to have a whirly bird on outside roof on outside roof of city house I sold with new furnace never had this problem would a whirly bird wind turbine solve this problem on this older house i just bought now

Generally speaking, in my experience and opinion, whirlybirds won't effect humidity to any great extent. There should be a vapour barrier (VB) between the attic and the lived-in portion of the house which stops moisture from being pulled up into the attic as a result of increased air flow from a whirlybird (same as VB stops moisture from penetrating inward). In some older houses though, depending on how well the attic is insulated, how much air flow there actually is, and the configuration of the venting, a whirlybird may increase the overall effectiveness of the attic insulation and would theoretically help with the humidity in the house. Installing a whirlybird wouldn't be my first course of action to address high or excess humidity. Just my opinion.  
 
Hope this helps

Agree with all previous posts. The issue is high humidity combined with limited air movements.  
 
Our previous house was heated with baseboard heaters. I kept a pry bar handy to open doors in cold weather. I tried adding a storm door. I eventually installed an air exchanger. Problem resolved.  
 
I was told having kids leaving door open was a plus as it allowed moisture to escape and dry air in.

You say it happens more overnight. Do you have curtains closed all night? If there is no air flow to the windows then there will be moisture on the windows in the morning. The windows on the north side won’t get the sun during the day which helps to equalize the temperature on/in the glass. This will also happen more with a dual pane window than triple pane window. The biggest thing I’ve found in my house and customers houses is to make sure the curtains are either not fully closed or opened right up in the morning so when the furnace kicks in and can get moving air it will clear up. In the winter time it is very dry outside. If you change the humidity to much in your house from winter to summer you will see changes in your house. Materials shrink and expand with moisture levels, window and door trim could split at the corners. You can also get nosebleeds if it gets too dry. With an air exchanger you can keep the humidity at a nice range all year. Not saying to get an air exchanger but it is an option if nothing else works. Good luck.

We do shut our blinds at night. Come morning, the curtains all get opened right up. It’s manageable on the nights it doesn’t get cold. On the nights it gets cold... its a lot of humidity on the bottom 3 inches of windows..the front door (glass insert), no curtains/blinds still get humidity on it and there is a ceiling fan going full right above it. Dehumidifier runs downstairs to control it. During the day it’s controllable.. it’s only at night. I open windows and front door periodically to let fresh crisp air in. The furnace gets turned down to 67 at night. We run it at 69 during the day. The new furnace doesn’t force air out of the vents as fast as before. I like the previous post suggestion to do the blue insulation.. we will install next fall for sure if we don’t do air exchanger before then. There was another suggestion to install a booster fan in but Is it possible to change the furnace motor speed to push out more air?

We have a wood furnace, humidity never an issue. Lack of is.