Domestic Hot Water Heat Exchanger Options

[Mister Twister]

I currently have a sidearm exchanger that is being heated from my CB 5036 on the side of a 40 gal gas hot water heater. My water heater tank is starting to leak so I will have to replace it soon. After a couple of showers we get cold water because of the slow recovery time of the sidearm. That's where I am at.

I have heard there are heat exchanges that supply endless hot water as the water passes through like a plate exchanger or something of that nature. Does anyone have information on these and what I may need? Number of plates, install before water heater, after? Pics on thier install etc.? Thanks in advance guys......:help:

 

[robsco]

I have 10 plate xchanger, it supplies unlimited 120-130 degree water with boiler water at 175. I put my exchangers in ahead of electric water heaters to temper water but they work so well I have had power to water heaters turned off for over a month with no problems. Bought them for around $100 on ebay

 

[Mister Twister]

When you say bought them on ebay do you mean you have more than one?

So you have this in front of your water heater? When the water heater is unplugged if you have not used any water overnight while you were sleeping do you have hot water when you take a shower in the morning? Is there a delay before it gets warm?

 

[robsco]

I have two of these on two seperate water heaters. One water heater is in an addition the other is in original part of house. I know from previous power outtages that the water in heater will stay hot for over 36 hrs. so no problem as long as you use some hot water every day. My original point was that since my heaters are turned off you should have no problem without a water heater/storage tank.

 

[Mister Twister]

Is it possible to post me some specs on the units you used or some pics of the install? I know you said 10 plates but what size is the unit? I see they come in 3"x8" , 5"x12" etc. I am sure the plate size makes a difference in btu capacity. I still need a hot water heater for the summer months I don't run my unit all year long.

 

[rx7145]

Also if you need a new hot water heater get a 80gal. It will help buffer the water temp. I would use a flat plate to pre heat the water going into the tank and use the side arm to keep the water hot. I use this and it works ok but a larger tank would make it work even better.

 

[robsco]

My units are 5x12 made of 316 s.s. I don't know how to post a picture but I will try to work on it. Another thing to consider is how hard your water is. I installed ball valves and boiler drains on the untreated domestic side. This will allow me to pump vinegar or similar cleaning solution through it to clean out deposits. I have an uncle who is a plummer and he does this with tankless gas or electric water heaters and says it works remarkably well. A larger plate exchanger or a side arm will require some type of tempering valve or you scald someone with 160+ water.

 

[mtfallsmikey]

Here's a note from "Mr. Safetee"

My units are 5x12 made of 316 s.s. I don't know how to post a picture but I will try to work on it. Another thing to consider is how hard your water is. I installed ball valves and boiler drains on the untreated domestic side. This will allow me to pump vinegar or similar cleaning solution through it to clean out deposits. I have an uncle who is a plummer and he does this with tankless gas or electric water heaters and says it works remarkably well. A larger plate exchanger or a side arm will require some type of tempering valve or you scald someone with 160+ water.

You need a tempering valve on any type of heater install. Scald injuries are nothing to sneeze at. Keep your outlet temps. at 120.

 

[Mister Twister]

This is all great information. I have a Honeywell mixing valve in my system now because the water got really hot when the sidearm system I currently have sat for quite sometime without use. Also learned what expansion tanks were all about after my last install.

I definetely like the idea of the boiler valves for cleanouts. Not quite sure what they are but I will find out before my new install.(Are they like garden hose spigots)? My water is really good now that we are connected to the public water system. My old well water would have plugged it up in no time at all.......

 

[upsnake]

What do you use to pump the cleaning solution with? I was originally thinking of doing my plate hx so that i could just take it out of the system completely and soak it in cleaning solution, but just closing a ball valve and running it through the boiler drain would be a lot easier.