How to Size Tankless Water Heaters
Tankless Water Heater Sizing Tips
A detail that is typically forgotten when sizing a tankless water heater is the size of the gas line.
Everyone must know that 3/4″ connections exist introducing the appliance. Sizing is not that simple!
A 3/4″ gas pipe will provide 273,000 BTUs per hour for a 10 foot run. If you have a 30 ft run you are down to 151,000 BTUs. Insufficient gas to run a conventional tankless appliance.
If you might provide that 30 foot run in 1″ pipe it will offer 284,000 BTUs. You can then lower the pipe at the connection to the unit. Trouble resolved.
It is likewise similarly crucial to included the various other gas home appliances in the house. A stove, furnace, heater will likewise be thirsty for sufficient gas. If everything is being made use of and it is the coldest day of the year you will quite potentially have a problem. Not just will you be making use of extra gas but so will your next-door neighbors.
The gas pressure might fall below what is typical. Something has to offer.
Let’s return now and look at that 30 foot run. If we kick the pipe size up providing the run to 1-1/4″ we will now have 583,000 BTUs offered. If pressure is lowered, no trouble, we can compensate.
You can see how something that might never be talked about will have a lifetime impact on the capacity of your gas home appliances to work.
There need to be no down side in having the biggest pipe running the lengthiest distance. Besides the preliminary expense I highly recommend this consideration. One last example:
If you had a 200 foot run of 3/4″ pipe you will only supply 54,000 BTUs. That exact same run at 1″ would be 102,000 BTUs while 1-1/4″ will provide 209,000 BTUs.
We like the following infographic that illustrates leading benefits of using a tankless water heater at home: