hot water from 35 year old boiler with tankless water heater

Steve Paul

At 35 years old, that boiler is almost ready to give up the ghost. The most efficient thing to do is to replace the boiler and install an indirect water heater along side of it. The next best option is to install a new gas/ oil/ electric water heater and abondon the coil in place. You can replace the coil. This might give you a few more years, but you might also snap off the bolts holding the coil in the boiler and wind up trying to drill and re-tap them out, possibly forcing you to by a new boiler if you can't get the bolts out. The final option is to install an electric water heater as a storage tank and have a small bronze circulator, circulate the heated from the coil to the tank. The water temperature can be controlled with the water heaters lower thermostat acting as an aquastat and the boiler low limit set as it is now set. Do not electrify the elements in the water heater just use it to store 30-40-50 gallons of the hot water made in the coil.

charlie holmes

have 35 year old hot water boiler with tankless water heater. boiler still works well for heating but water pressure and temperature fluctuates for domestic water, sometimes becoming lukewarm with pressure drop. There is checkvalve on cold supply to tankless, and two 2 handle old style non-pressure balancing t/shower valves, as well as old laundry tray faucet where cross connection between hot and cold water could occur. what are possible causes and solutions for this problem. Another contractor has suggested build up in tankless restricting flow.

John@Reliable

Just have the

coil replaced. Yes some of the bolts may break,I price our jobs betting atleast 2 will. Drilling and tapping is no big deal.If a new system is in the budget now would be a good time as boiler is getting to that point. Depending on house and lifestyle tankless hot water heaters are still a good way to heat your hotwater. But every system depends on a good installation from the start. I would have afew pros take alook and go with what they say. John@Reliable